# Mason Bogie Live Steam Won't Run



## RefrigEng (May 18, 2014)

I apologize in advance for the use of improper terminology. I am new to this hobby. I have Accucraft Mason Bogie on rolling gear. I steamed it up twice now and can't get it to move its rods. After about ten minutes, I am able to raise up to 45 PSI with the throttle closed, and I have tried a number of throttle and the reversing gear settings. I set the steam throttle at about 1/8 turn open and the reversing gear in reverse. I tried cycling through forward and reverse. How much butane valve opening is appropriate? The last time I had it open 1/2 turn open. I can achieve slightly more than 20 PSI. But if I open the throttle to 1/4 turn open, pressure drops below 20 PSI. Steam issues from the stack, but the rods never move. I am able to manually move the wheels, but the loco makes no attempt to take off.


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## David Leech (Dec 9, 2008)

Dear RefrigEng,
Welcome to MLS.
Do you know if you live anywhere close to another experienced live steam enthusiast?
By the sounds of it, you need to have someone see and hear what is going on.
Could be a loose connection, or if you have had it upside down, maybe a D valve has lifted, so that the steam is just exhausted straight through.
Hopefully nothing too serious.
All the best,
David Leech, Delta, Canada


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## Charles (Jan 2, 2008)

RefrigEng said:


> I apologize in advance for the use of improper terminology. I am new to this hobby. I have Accucraft Mason Bogie on rolling gear. I steamed it up twice now and can't get it to move its rods. After about ten minutes, I am able to raise up to 45 PSI with the throttle closed, and I have tried a number of throttle and the reversing gear settings. I set the steam throttle at about 1/8 turn open and the reversing gear in reverse. I tried cycling through forward and reverse. How much butane valve opening is appropriate? The last time I had it open 1/2 turn open. I can achieve slightly more than 20 PSI. But if I open the throttle to 1/4 turn open, pressure drops below 20 PSI. Steam issues from the stack, but the rods never move. I am able to manually move the wheels, but the loco makes no attempt to take off.


Seems to be quite a few situations at hand: steam pressure drop, lack of motion along with gas delivery. So, how long have you had the engine and have you contacted Cliff at Accuraft?
Low steam pressure- could be a jet or debris in the blockage. Have you tried to clear and clean the jet? When you fire the locomotive do you bleed off the liquid gas prior to lighting the engine? Does the flame kick back onto the burner? What color is the flame?

Open throttle- no go. Could be piston rings, loose piston head, steam leak in delivery pipes, throttle leak all point to the loss of steam pressure.

No movement: hydrolock, wheel(s) out of quarter, piston head loose, out of timing, screw hitting somewhere on the rods, etc. Does the valve gear and wheels move- engine move when not under steam?

Just some indicators of what to check. As David indicated if someone with experience of this engine is available visit them.


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## Scottychaos (Jan 2, 2008)

RefrigEng said:


> I apologize in advance for the use of improper terminology. I am new to this hobby. I have Accucraft Mason Bogie on rolling gear. I steamed it up twice now and can't get it to move its rods. After about ten minutes, I am able to raise up to 45 PSI with the throttle closed, and I have tried a number of throttle and the reversing gear settings. I set the steam throttle at about 1/8 turn open and the reversing gear in reverse. I tried cycling through forward and reverse. How much butane valve opening is appropriate? The last time I had it open 1/2 turn open. I can achieve slightly more than 20 PSI. But if I open the throttle to 1/4 turn open, pressure drops below 20 PSI. Steam issues from the stack, but the rods never move. I am able to manually move the wheels, but the loco makes no attempt to take off.


Refrig,
based on your post, two things come to mind for me:

1. Steam throttle at 1/8 open isnt open very far..you might not be getting enough steam to the cylinders..try opening it up 50% or more to get the wheels turning.

2. Many live steam locomotives need a "shove" to get things running..some wont take off by themselves from a dead stop, without help..easy to do on track..just push the loco forward a bit to get the wheels turning..On rollers try turning a driver by hand, once steam pressure is raised..Wait until steam starts to seep out of the safety valve, put the throttle in forward, then try to spin a driver by hand..that might get things moving!

Scot


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## Pete Thornton (Jan 2, 2008)

RefrigEng said:


> I apologize in advance for the use of improper terminology. I am new to this hobby. I have Accucraft Mason Bogie on rolling gear. I steamed it up twice now and can't get it to move its rods. After about ten minutes, I am able to raise up to 45 PSI with the throttle closed, and I have tried a number of throttle and the reversing gear settings. I set the steam throttle at about 1/8 turn open and the reversing gear in reverse. I tried cycling through forward and reverse. How much butane valve opening is appropriate? The last time I had it open 1/2 turn open. I can achieve slightly more than 20 PSI. But if I open the throttle to 1/4 turn open, pressure drops below 20 PSI. Steam issues from the stack, but the rods never move. I am able to manually move the wheels, but the loco makes no attempt to take off.


Your photo shows a lot of r/c gear - so presumably you added the servos or bought the loco with them?

Have you turned it upside down to see if any of the rods or other links are dangling down because a screw/bolt has dropped out? If the valve piston isn't being pushed in and out when you turn the wheels, it won't go but will exhibit many of the symptoms you describe.


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## Garratt (Sep 15, 2012)

Turn it over and make sure the valves all cycle in and out when turning the wheels.
You may need a little more heat to keep the steam pressure up. The safety valve should blow when there is excess steam anyway. That can be your indicator to back off the butane a little.
At first when the cylinders are cold it they will lock up because the cooled steam has condensed into water so give it a shove both ways with the reverser set in the correct direction to clear the condensed water out. Try a bit more steam throttle if nothing happens. 

Andrew


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## placitassteam (Jan 2, 2008)

The Bogies use a lot of steam, large cylinders, small boiler. I find on mine that I have to run with a pretty high gas setting. If you can't get over 20 psi something is wrong with the burner. Also if the pressure drops right away when you open the throttle you may not have enough steam space in the boiler. Did you draw out 30 cc's of water after filling the boiler full? The water level sight gage shows about half when the water level is right. Watch the water level very carefully because the Bogie only has about 150 cc's of usable water in the boiler and it is very easy to run it dry. (Don't ask how I know!) It has a complicated valve gear so check to make sure everything is doing what it is supposed to. If it still has the detents in the valve gear you may not be getting proper travel in the expansion link. When I converted to RC I removed the detent and made lifting rods which do not have the slotted connections on the end. You can see my complete thread on installing RC on 2 Bogies at http://forums.mylargescale.com/18-live-steam/19634-installing-rc-mason-bogies.html


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## RefrigEng (May 18, 2014)

I was hoping for a response, and I am blessed with five. I will try to address generally and then specifically. I have been an avid reader of this forum so it’s the first thing I thought of when I was stymied. Actually, I was hoping there was something basic that I missed, and it would be pointed out to me. I purchased the MB new in January, and had fun over the winter months installing the R/C. There are servos for the throttle and reversing gear. The throttle will give me just over 90° of travel. I will have to move the throttle servo if I need more than 180° of butane valve opening. These two attempts were the first.
David, I am not aware of another live steam enthusiast in the area, but I will ask around. I am in the Chambersburg, PA area. I have had the loco upside down. I do have a feeling the steam is blowing through something, but it looks like all of the connections are tight. I do see some minor bubbling issuing from the seam between the D valve and the piston head (red line on photo) on both sides.
Charles, I did clear some debris from the gas nozzle using the gas method described by so many folks in this forum. I was then able to see through the tiny hole. I feel the flame is good. It sounds robust, similar to a propane lamp. I see the blue crescent. I was a little alarmed that the superheat tube was glowing in one spot, but I guess that must be normal. I felt like there was little if any change in flame size from 90 to 180° on the butane valve. The flame popped back and was never in the smoke box. I am able to move the wheels by hand and all of the rods and gear seem to be moving correctly. The piston heads are solid.
Scot, the throttle servo limits the throttle opening to maybe 90 to 100°. When I had the servo at max throttle, the pressure headed for less than 20 PSI. I do not have a track yet (flex 332 USA brass in a box). A was able to move the wheels a bit on the rollers under steam and throttle. They stuck slightly, then moved readily (slight resistance), but made no attempt to continue. I will try your suggestion to let the relief valve simmer at 60 PSI before opening the throttle. Then my next move may be to remove the throttle servo so I have more flexibility.
Pete, I have had the loco upside down, and all of the rods and gear seem correctly connected. The complete gear moves readily with a resistance feeling like lubed o-rings and periodic trapped pneumatics. The piston rods stoke roughly ¾” and the D valve rods stroke roughly 1/8” to 3/16” (by eye) when I move the wheels. No missing parts that I can see.
Andrew, your comments along with others leads to trying more heat for higher pressure. I will try again next weekend.
Winn, I read your post and studied your photos fifty times. Thank you! I did remove the detents, but I retained the original lifting rods. I think I have the full stroke on the reversing gear. I did have a brief scare when I thought I ran the boiler dry. I may have gotten close, but I do not think I damaged anything. Thanks for the tip regarding half full on the level gauge. I read the instructions regarding 30cc, but I guess I underestimated the importance. Lesson learned.
Here’s a pic of the rod gear. The circled ornamental fitting (I hope it’s ornamental) was loose so I hand tightened it. That can’t affect the D valve can it?
Thanks, all.


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## Dr Rivet (Jan 5, 2008)

SO.... you did not test the locomotive AT ALL before you installed the R/C to make sure everything was working first?

I would put some track together so you can move the loco back and forth just to clear the condensate out of the cylinders. This is not as easily done when the loco is on a roller stand.


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## placitassteam (Jan 2, 2008)

You are right, that is a simulated oiler and has no effect on the operation on the loco. The photo shows that you are getting full travel on the expansion. I am at a loss to explain why you are only getting 20 psi when every thing seems to be OK. 180 degrees on the butane valve should be more than enough although going from 90 to 180 should made a noticeable difference. A throttle opening of 90 degrees should be enough unless something else is restricting the flow. I'm sorry I cannot think of any other suggestions. If you are trying to find leaks a stethoscope works great. This thread shows how I built one that can find very tiny leaks. Just be careful not to blow your ears out on a big one! http://forums.mylargescale.com/18-live-steam/26444-steam-escaping-cylinder-front.html


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## Charles (Jan 2, 2008)

If you are taking 15 minutes for steam up on this size boiler than there is a heat problem (even if boiler is full) only getting up to 45 psi. Secondly, a drop in 20 psi once throttle is open seems to indicate a steam leak (possible blow by related to pistons). Also, could be a cracked superheater tube (normal for it to glow red).


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## Charles M (Jan 2, 2008)

I have been reading on the possible solutions to the problem. It is possible the D valve has lifted off of the seat in the valve chest. If the motion was moved when the model was upside down this can happen . ( Been there , done that on Roundhouse and Accucraft models .) You can also lift the D valve by hand pumping or priming in the boiler. 

A friend had a new Mason Bogie and managed to lift the D valve by pumping water with the hand pump so hard he had water coming out of the safety valve. At this point the loco wouldn't move. A call to Cliff told us how to fix the problem. 

With the model sitting on track, lift the engine up at the front till the 1st driver is clear of the rails about 3/4 to 1 inch high. The rear driver will need to stay in place on the rails. Let it drop back onto the rails. This action will snap the D valve back onto the seat. It sounds worse than it is, but it works just as described. The model was operational just as soon as this was done !! 

Charles M SA # 74


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## bonzo1953 (Dec 27, 2007)

I had a similar problem with my Ruby (my 1st gas fired engine) years ago. I did not understand that the fire had to go back under the poker burner. I was burning gas in front of the poker. Took a long time to build steam and pressure dropped off during running. I could only run a short distance. Throttle back on the gas to get the flame under the poker, then turn it back up. Check to see that it stays under the poker (burner tube). A partially plugged jet may make it difficult to get the flame to pop back on the burner. Or a loose or poorly sealed jet will cause this problem. Gas should not flow past the jet threads.
There is more than this possibility going on. I like the lifted valve theory. If you have a lifted valve, steam will blow out the stack when the throttle valve is opened.
Best of luck.
Keep 'em Steamin'
John


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## RefrigEng (May 18, 2014)

Thank you for the additional posts. Such a wealth of information. I have a number of strategies for my next attempt - including the engine drop valve adjustment! I will try to get some track laid soon. I appreciate that it will make things easier. Incidentally, I just emptied the boiler to try to get a sense of the capacity and the 30ml trim. I removed about 100 ml. The glass is still indicating 2/3 full. Something blocking connections? Steam oil? Also, I drained little and less water out of the lubricator after each attempt. I will post again when I know more. Thanks, all!


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## Nick Jr (Jan 2, 2008)

Please don't rely on the site glass, they are notoriously incorrect. I think they are provided just for the ability to say it is on the locomotive. And don't believe the "wire in the site glass", great when it is cold, but just as useless when the locomotive is really boiling water. I've had no success with that at all. There are some that just parrot the use of them. 
Your best bet is measure what you put in to an empty boiler. 
I do hope you figure out what is causing your's not to run properly, I do really like mine.


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## RefrigEng (May 18, 2014)

Thanks, Nick. I am getting that impression about the glass. After about half an hour after removing all water from the boiler, the water disappeared from the glass. Today, I verified all water removed and refilled to the top with 105ml. After I removed 30ml, the level is at about 3/4 glass. If I measured correctly, he tender pump-tank holds about 200 ml.
I executed Charles' valve adjustment procedure last night so I am psyched to try again this weekend. Happy Memorial Day!


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## Charles M (Jan 2, 2008)

You may find that you have to steam up and warm the oil in the valve chests up. Steam oil is very sticky and may not let the valve drop when it is cold. Try running it and see , but if it doesn't run , try again after the cylinders get warmed up. 

Charles M SA#74


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## RefrigEng (May 18, 2014)

Thanks, Charles. Will do.


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## Charles (Jan 2, 2008)

Charles M said:


> You may find that you have to steam up and warm the oil in the valve chests up. Steam oil is very sticky and may not let the valve drop when it is cold. Try running it and see , but if it doesn't run , try again after the cylinders get warmed up.
> 
> Charles M SA#74


Probably too heavy steam oil if this was occurring.


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## Nick Jr (Jan 2, 2008)

RefrigEng, have you made any progress?????


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## RefrigEng (May 18, 2014)

Ah, regrettably, no. I tried again today, and the results were the same. I really think I'm overdoing it on heat, but I could be wrong. This time there was a different sound toward the end of the session, which rattled me a little. The sound level diminished for some reason. Also, when I turn off the gas, the roaring usually stops quickly, but this time it sounded like the flame was still on and took a minute to die off. I am planning to contact Accucraft for help. This seems to be beyond me.

Thanks everyone for your help,
Hugh


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## Nick Jr (Jan 2, 2008)

can you make a video of it with sound?? post it on UTube and then post the link. Maybe some can see or hear something to help.


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## RefrigEng (May 18, 2014)

Nick, I did not have a video, so I made one during attempt #4 today. You will find it here 



 Thanks for your interest!


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## Gary Armitstead (Jan 2, 2008)

Save yourself the frustration and call Cliff at Accucraft.


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## Skeeterweazel (Feb 11, 2014)

Hugh, do the cylinders get hot under steam? Wondering if you have a cracked line like Charles mentioned. Steam leaking out of crack instead of getting to cylinders. Is it possible to take the smoke box door off and see where a leak may be? Steam out of the stack is coming from cylinder exhaust or somewhere else? Just a thought from a fellow newb.
Marty


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## llynrice (Jan 2, 2008)

It appeared that the pressure dropped very quickly from 60 psi when you opened the throttle and pushed the loco. I wonder if steam is even getting to the cylinders. If memory serves, the Mason Bogey has a rubber tube to the pivot point. Have you been able to check and see if all of the connections are tight and have you looked for steam leaks from the underside when you open the throttle? These gauge #1 steamers can sometimes be problematic; but, they are wonderful fun when you sort them out.


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## David Leech (Dec 9, 2008)

Well ..... I know little about this particular Accucraft loco, but some more thoughts.
Excellent piece of video to demonstrate what is going on, and you seem to have a good handle on live steam.
I hate the sound of a roaring gas fire!
I am surprised how long it seemed to take to get to pressure, being a fairly small boiler.
I would have thought that 90º of throttle might not be enough, but maybe on this loco it is.
Maybe remove the servo linkage next time and open the throttle more by hand, and turn OFF the burner when you do it so that you can hear if the steam is indeed leaking somewhere.
I would keep trying for a bit more before you send it to Cliff.
All the best,
David Leech, Delta, Canada


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## RefrigEng (May 18, 2014)

Thanks, guys. I looked for leaks while under steam. When I open the smoke box door, I see nothing that looks like a leak. There was a good bit of water along the track when I was done. There are two tubes at the pivot. One looks like a polyethylene derivative and is more rigid (supply) and the other is a softer clear tube (vent). Both appear to be intact.

I don't have Cliff's number per se, but I did send my contact info and the link to the video to Accucraft today to get things started. I am sure that I will get past this eventually.


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## Steve Ciambrone (Feb 25, 2014)

Looks like you are not getting any steam to the cylinders, does not even seem to have any condensate to clear when starting, turn off the burner and look for steam leaks under the engine, you are losing pressure too fast. Steam leaks can be hard to find, especially in dry weather, a small piece of tissue will act as a flag. If it is too difficult to look under the engine when hot you could attach compressed air to the boiler at low pressure and then have the engine upside down to look for leaks 10-20 psi max.

Steve


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## Semper Vaporo (Jan 2, 2008)

I thought I saw a bit of a chuff from the chimney the first time you opened the throttle and gave the engine a shove... I would be betting that you have a cylinder valve that is not seated properly and steam is going straight from the in pipe right to the exhaust pipe. As was suggested, turn off the gas to quiet the fire and then open the throttle and I bet you still see steam coming from the stack and hear a whooshing sound from both cylinders... odd that BOTH would be unseated, but it could happen. Maybe one is so open that all the steam is blowing past it and there is no pressure available to go to the other side of the engine.


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## Garratt (Sep 15, 2012)

You seem to continually have steam coming from the stack when the steam throttle is open.
That suggests steam is getting past the valves and being exhausted or the join from the steam delivery pipe is loose or cracked in the smokebox.
There is some hidden plumbing on the mason bogie because of the swiveling engine bogie.
Try viewing the silicone tube to the bogie from the right hand side under the smokebox. You could also try putting a mirror between the rails to view the silicone tube from bottom if it is leaking. Removing the pilot first will give a better view. If it was leaking here I would expect to see steam come out from the sides rather than out the stack though.
Just for the record, does it have an axle water pump? I would presume that would have the equivalent to a goodall valve and would leak water if those lines were loose.
I am intrigued with your frustrating loco.

Andrew


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## David Leech (Dec 9, 2008)

Semper Vaporo said:


> I thought I saw a bit of a chuff from the chimney the first time you opened the throttle and gave the engine a shove... I would be betting that you have a cylinder valve that is not seated properly and steam is going straight from the in pipe right to the exhaust pipe. As was suggested, turn off the gas to quiet the fire and then open the throttle and I bet you still see steam coming from the stack and hear a whooshing sound from both cylinders... odd that BOTH would be unseated, but it could happen. Maybe one is so open that all the steam is blowing past it and there is no pressure available to go to the other side of the engine.


That is, of course, assuming that the builder remembered to place the 'd' valves in there!!!
All the best,
David Leech, Delta, Canada


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## Charles M (Jan 2, 2008)

Another possibility is that the eccentric crank has shifted position and is not allowing steam to be admiitted at the correct time or not at all . I had a friend that had a K36 that would not run , and I found that the eccentric crank on the right side slipped and wasn't moving the valve at all. Could someone post a picture of the correct position for a Mason Bogie in the classic " rods down position " for reference. ( From someone who has one that runs .) I don't have one so I can't help here. 

Charles M SA#74


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## Garratt (Sep 15, 2012)

The Mason Bogie has Walschaerts Valve Gear so no eccentrics.
These pictures probably aren't relevant to the problem at hand but will give some a better idea of what is going on with the steam lines to and from the bogie. 

Andrew


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## Nick Jr (Jan 2, 2008)

RefrigEng, you seemed to be able to push that locomotive with ease. Mine will lock the wheels especially at the peak of the compression stroke (all the way forward or back) of the cylinder when the throttle is off and the direction bar is in the center.
Another observation, you said it is easier to push it in the direction of the direction bar, easier Fwd when the linkage is in that position and Rev when in that direction. So some steam is getting to the cylinders, but not very much. 
No help, but that's what I got from it. When Cliff see's it he will surely be more helpful, or he'll recommend an authorized repair person to send it to.


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## Garratt (Sep 15, 2012)

Don't pull apart your toys! Yeah yeah, I know...
I just had to have a look.
If the hex screw were loose on both sides that set the valve, you would have a problem.
It was very easy to pull the tops off the steam chests by first unscrewing the fake oiler them undoing 4 nuts.

Andrew


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## Nick Jr (Jan 2, 2008)

Garratt, that looks simple enough. How much clearance is there from the top of the block that the valve rides on to the deck that fits on the valve chest?? Just curious.


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## Garratt (Sep 15, 2012)

Nick, I'm not quite sure what you mean but the chest itself is approximately 9mm deep. There is about 1mm clearance above the valve hex screw and the steam chest top plate has a slight recess above that. The steam chest top plate, it's nut space and the cover plate bulk up to about 4.5mm in total.
The valve can freely lift as previously explained by perhaps 1mm or so. 

Andrew


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## bille1906 (May 2, 2009)

This may seem like oversimplification but 3 ml removed from a full boiler may be too little.
Try it with the boiler half full to see if it will run that way.


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## Garratt (Sep 15, 2012)

He has tried 30 ml less than full which is what I have been doing on my live steamers.

Andrew


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## Nick Jr (Jan 2, 2008)

Garratt, that is exactly what I was looking for, THANK YOU. Nothing to help RefridgEng, but now i know what I am looking at when I have to replace the gaskets as I have a few that weep right there.


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## Charles M (Jan 2, 2008)

The eccentric crank is attached at the point on the locomotive where the main rod is attached. If the position of this is incorrect steam will not be admitted at the right time or not at all.
When I had the prototype Mason Bogie for a week I told Accucraft they needed to change the Johnson bar connection to make the valve gear move in the correct direction when running forward . They took my advice and implemented the change. 
A good explanation of valve gear operation was writen up in Trains Magazine , May 1984 by E.W. King and illustrated by Allen J. Brewster. 

Charles M SA#74


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## Charles (Jan 2, 2008)

Could be piston rings allowing blow bye thus steam up the stack, limited movement. Timing could reflect lack of movement and power.


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## Garratt (Sep 15, 2012)

I understand what you meant now Charles M.

Andrew


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## RefrigEng (May 18, 2014)

Wow, where to begin. First, this feedback is solid gold. Thank you all very much. Against everyone's better judgement, I went into the valve chests. I haven't had this much fun in years (sad, I know). Anyway, they look good. I cannot speak for the relative positions. The one on the left does not expose the forward piston feed hole on its stroke as much as the one on the right (as shown in pics). They were both sitting on the valve deck. I can see how it might be possible for them to stick to the cover plate. I have checked the various joins for signs of looseness or leakage and found nothing yet. I like the idea of putting some air pressure on the boiler and checking for leaks - maybe a glycerine/soap bubble check with a brush? I hope piston rings are OK. For the moment, I believe in Occam's razor. If I missed acknowledging anyone's comments, please excuse me. There is so much! Incidentally, I don't find any of this frustrating, though I do expect this engine to run eventually.
p.s. how do I get a copy of the _Trains Magazine_ , _May 1984 by E.W. King_ and illustrated by Allen J. Brewster?


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## Garratt (Sep 15, 2012)

It is odd how your valve does not entirely clear the holes. See my pics, they clear them and some more.
Check the eccentric crank compared to mine below as Charles M was explaining.
It is all an education this. I'm having fun too. 

Andrew


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## Charles M (Jan 2, 2008)

Andrew , That is exactly the picture I wanted to be shown. Thanks . It shows the position of the eccentric crank in relation to the wheel position. If it is not in the correct place, it can be moved to provide the correct motion. I have adjusted 3 Accucraft Locos to correct this position as 2 had slipped in shipping . The last one on my Earl was set up to run in the reverse position , looked funny running. 

The only place where you can see valve gear events running is this website.

http://www.billp.org/Dockstader/ValveGear.html

Can't help with the article location however. 

I have downloaded all of the diagrams and find it very useful. The have Walschaerts valve gear in outside admission just like the Mason Bogie so it would prove useful in seeing how things should work on the model. 

Using soap solution to check for leaks is just the thing. Had to do this with an Aster Climax in just the last month. Finally got all of the leaks fixed , wouldn't have been able to find them with doing this. 

Charles M SA#74


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## cocobear1313 (Apr 27, 2012)

If you have one, a hobby air compressor with the standard airbrush fittings has the same thread as many Accucraft fittings. If you attach it say, in place of the pressure gauge, as fast as your pressure leaks down, it should be very apparent where the leak is. Best of luck!

Dave


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## David Leech (Dec 9, 2008)

Charles M said:


> Andrew , That is exactly the picture I wanted to be shown. Thanks . It shows the position of the eccentric crank in relation to the wheel position.
> 
> Charles M SA#74


I know that you all know what you are talking about, but just to correct the terminology, what we have here is actually called a RETURN CRANK.
All the best,
David Leech, Delta, Canada


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## Garratt (Sep 15, 2012)

I don't think the problem is a leak. It seems as though the valve is not being thrown correctly probably due to the 'return crank' not set where it should be. 

Andrew


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## David Leech (Dec 9, 2008)

RefrigEng said:


> Wow, where to begin. First, this feedback is solid gold. Thank you all very much. Against everyone's better judgement, I went into the valve chests. I haven't had this much fun in years (sad, I know). Anyway, they look good. I cannot speak for the relative positions. The one on the left does not expose the forward piston feed hole on its stroke as much as the one on the right (as shown in pics). They were both sitting on the valve deck. I can see how it might be possible for them to stick to the cover plate. I have checked the various joins for signs of looseness or leakage and found nothing yet. I like the idea of putting some air pressure on the boiler and checking for leaks - maybe a glycerine/soap bubble check with a brush? I hope piston rings are OK. For the moment, I believe in Occam's razor. If I missed acknowledging anyone's comments, please excuse me. There is so much! Incidentally, I don't find any of this frustrating, though I do expect this engine to run eventually.
> p.s. how do I get a copy of the _Trains Magazine_ , _May 1984 by E.W. King_ and illustrated by Allen J. Brewster?


In order to get a nice even running loco, it is best to have ALL FOUR openings (ports) made even, even if they don't fully uncover the 'hole'.
The steam will get through a very small hole.
So, how does the back side of the valves look in relation to the front as far as covering the ports?
Make sure that you use a small screwdriver or something to lightly press onto the valve block while turning the wheels to act as the steam pressure to take up any slack that might be in the system when checking port openings.
While you have it open, I would adjust the valve block to even everything out if necessary.
All the best,
David Leech, Delta, Canada


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## Charles (Jan 2, 2008)

Garratt said:


> I don't think the problem is a leak. It seems as though the valve is not being thrown correctly probably due to the 'return crank' not set where it should be.
> 
> Andrew


Seems more to it than just timing issue. A quick and large drop in steam pressure does not usually occur due to timing. Normally, an engine a bit out of time will run but will have a loud and ragged beat to it. So, once the timing it properly set then it is onto the next cause and effect.


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## Charles M (Jan 2, 2008)

An interesting aside to this discussion. The terminology " return crank " appears in the diagrams of books I have that are printed outside of the United States. The terminology " eccentric crank " is used in diagrams of books printed in the United States. Hmmm ! A Bogie is a Fairlie too. 

Charles M


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## David Leech (Dec 9, 2008)

Charles M said:


> An interesting aside to this discussion. The terminology " return crank " appears in the diagrams of books I have that are printed outside of the United States. The terminology " eccentric crank " is used in diagrams of books printed in the United States. Hmmm ! A Bogie is a Fairlie too.
> 
> Charles M


Ah, my apologies then.
Being of British upbringing, and having books from there, I had not thought that the US would use that term.
All the best,
David Leech, Delta, Canada


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## Nick Jr (Jan 2, 2008)

Assuming all parts are manufactured to the same spec. it looks like the rod that moves the valve on your locomotive has much more protruding from the front of the valve than Garratt's. Maybe one hole is exposed most of the time and the other hole is never allowed to be exposed. ????????


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## Garratt (Sep 15, 2012)

It does look like that Nick but I would imagine checking the correct geometry of the eccentric crank (return crank) would precede the setting of the valve position. I wouldn't trust that anything was correctly set at this stage. Someone may have unsuccessfully fiddled with the valves because the eccentric crank was incorrect. 

Andrew


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## Nick Jr (Jan 2, 2008)

Andrew, as you said, adjusting things in the correct order will lead to a great running loco. 
Was this purchased used? 
I'm anxious to see a video of it running, and am sure RefridgEng would like to see it run more than all of us.


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## bille1906 (May 2, 2009)

I believe the Accucraft valve throw is still 4 mm. This can be measured with a digital caliper. If both sides are 4 mm then the eccentric cranks are ok, if one is less or more, then it has slipped. Once this is checked, the valve should be adjusted for equal port openings on front and rear.
Excessive blowby could be that the piston has slipped off the rod. This is not common but it happens to some Accucraft engines. Check this by taking the front cylinder cover off and rotating the wheels. If this is the case, it can be reattached with 680 loctite


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## Garratt (Sep 15, 2012)

The valves on my Mason Bogie throw approximately 5.5mm in total.
I've misplaced my calipers so I can't give a perfect measurement.

Andrew


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## bille1906 (May 2, 2009)

Andrew
I remember Dave Hottmann saying that a few have longer throws but I thought he said they were 5 mm
I wonder if someone else has a Mason Bogie which they can measure. It is important to know the factory setting as this needs to be checked before you start adjusting anything else. if it has slipped, the throw may be shorter or longer depending on which way it went. Matching one to the other will work only 50% of the time.


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## RefrigEng (May 18, 2014)

I need to study the timing subject, but this evening I pursued the leak angle. I connected some air at low pressure - not even registering on Bogie's gauge. Sound immediately emanated from the stack. I rigged a stethoscope to some brass tubing and probed the engine joins and pivots. There was a lot of noise in the stack and less but alarming noise in the smoke box and boiler tube (term?). I could not tell for sure if there were leaks in addition to the air blowing through the pistons and out of the stack vent tube. I listened for a difference in pitch or volume as I rotated the wheels, but there was very little change. So I removed the stack and pinched the vent tube holes closed. The whole engine was quiet up to 20 PSI. All of the joins and pivots were quiet. I believe the air was rushing through the pistons with little resistance and venting from the stack. Now I plan to study the discussion regarding timing. I visited Trains Magazine web site and registered. No references to back issues into the 80's Thanks again, folks.
p.s. I purchased the Bogie new from Accucraft in January.
p.p.s. Andrew, the right side rods and cranks on this Bogie align with your photo.
p.p.p.s. I downloaded the Dockstader programs, thanks, Charles M. Thanks for the primer on Fairly and bogie.
4p.s. David, I assume that you mean that the equivalent amount of hole is uncovered at each end of the stroke?
5p.s. Bill, blow-by resonates with me right now. I will investigate the front cylinder cover tomorrow.


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## Semper Vaporo (Jan 2, 2008)

Just to clarify a couple of aspects of the valve settings:

The Eccentric/Crank Arm should be at 90° to the Main Pin on the wheel. The apex of the angle is the center of the Axle. See the drawing below for where that angle is measured!

Another thing that maybe has not been stated clearly is that the eccentric crank arms should both be in the same direction from one side of the loco to the other and there is always some confusion when you look at one side of the engine and then turn it around to view the other... You have to remember that in doing so you have just reversed the direction of "forward" so, Clockwise and Counter-Clockwise (or Anti-Clockwise for my friends across the pond) is a poor choice for a description! To eliminate any confusion, if you roll the engine forward, both eccentrics should either be Leading or Lagging (following) the Main Pin. If the Valves are "outside admission" (like your engine is) then the Eccentric should Lead the Main Pin. (NOTE: The drawing implies that the front is to the right, because the Main Rod goes off in that direction, thus it shows the Eccentric Arm "Lagging" the Main Pin, which is the opposite of what you want on your engine. I made the drawing for my 'Valve Gear' article series in "Steam in the Garden" magazine [2006] and I drew it that way because it is easier to "SEE" the angle that way instead of obscuring it behind the Eccentric Rod.)

When you roll the engine and watch the valves, they should both move the same amount (but are separated by 90°; i.e.: when one is at full travel in one direction, the other should be in the middle of its travel) Both should expose the steam passages to the cylinder an equal amount in both forward and reverse.

The distance traveled is controlled by how far Lifting Link from the Reverser Lever (in the cab) moves the Radius Rod (from the Valve to the Expansion Link) in the Expansion Link [that slotted, curved doohickey that is being wiggled by the Eccentric Rod as the wheels turn.] (How's that for technical jargon!)

When the Radius Rod is in the center of the Expansion Link the Valves will move only a very small amount and when the Radius Rod is as far as it will go in the Expansion Link (either up or down) the Valves should move the maximum amount.

If either Eccentric Arm has slipped in its attachment to the Main Pin then you need to set that first.

If the Lifting Links are not moving the Radius Rod to the same position in the Expansion Link then those may also need to be tightened to the common axle they are on. When the Reverser Lever is in the middle position, the Lifting Links should put the Radius Rods in the center of the Expansion Links.

If you get all these settings right, and assuming the manufacturer made all the parts right, then you do not need to know more about Valve Gear.


By your latest test, I guess it seems like you are getting "blow-by" in the Cylinders. Time to pull the front Cylinder heads off to see if you have a problem with the Piston Heads and Rings.


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## RefrigEng (May 18, 2014)

Semper, I am in awe of the information now contained in this thread. Thank you for your post. Even if this is a simple piston attachment or wear issue (how could that be?), I will understand the timing subject. Always more tomorrow!


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## bille1906 (May 2, 2009)

How could that be...
On a new engine, I can only think of three things
1. rod hole in piston is oversize and the press fit is not strong enough and the piston is now sliding on the rod.
2. forgot the piston rings
3. wrong piston is used.


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## RefrigEng (May 18, 2014)

I took a peek under the front cylinder covers. They looked good, no debris or disconnected pistons. I am now in contact with The Train Department for professional help. Thank you all for your comments. I will be back with a report when the train is running.

Hugh


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## RefrigEng (May 18, 2014)

*Finally Runs*

I wanted to tie up this loose end. It has been more than a year since I chronicled my problems trying to get my Mason Bogie to run. The Train Department did a marvelous job with the loco. The flexible steam lines were damaged by heat transferring from the smokebox to the unions. I was guilty of running the gas valve open pretty far as I tried to get a reaction. Not sure exactly how I got there, but I am very pleased by the way things turned out. The engine runs very well. If anyone is so inclined, I posted a video of my run on YouTube. Thanks again for the feedback.




.


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## bille1906 (May 2, 2009)

Interesting
Jason
Were the lines melted so that they were blocking the steam
Are they silicone or PTFE?


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## Kovacjr (Jan 2, 2008)

Leaks were external and tubing gone; steam leak was under the smokebox resonating through the opening. Melted through from overheating through the smokebox opening. Were a plastic type not 100% sure. The Roundhouse used teflon and special fabricated clamps and fittings. This is simlar in hardness. Ive replaced with the shielded tubing as its high temp rated for sitting near exhaust manifolds on autos.


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## bille1906 (May 2, 2009)

Yes
Those smokebox fires will do you in every time

I've used PTFE (teflon) tubing with success when a dog bone connection isn't practical
As Roundhouse does I have special fittings which are shown in my "Making Parts" thread. Haven't had any fail yet but I would think they would melt if they got hot enough

I am trying to recall what tubing is used in autos that holds up to this heat level but you have me stumped.


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## Kovacjr (Jan 2, 2008)

I am using Diesel fuel lines from Benz. Its the braided hose I sell.


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## zubi (May 14, 2009)

Jay, what is it braided with? Unless it is braided with metal such as stainless steel I do not see why it should not burn. In fact if braided with fabric it will burn more easily. Although it will not melt as easy as whatever stuff is used by Accucraft. I doubt they use teflon, its melting point is 326 degrees Celsjus. The locomotive would fall apart before reaching this temperature... I guess teflon tubing is optimal from the point of both flexibility and heat resistance. Best wishes from Tokyo, Zubi


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## bille1906 (May 2, 2009)

Zubi
It sounds like there was a smokebox fire which could have raised the temp over 326c (611f) but I agree that teflon is probably best. That being said, the braided tubing sounds interesting.

Jay, is it your TD102 that is on your site?
Do you attach it with normal hose clamps? 
What is the outside diameter?
Have you done any tests on it for heat resistance?


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## zubi (May 14, 2009)

Bill, OK, smokebox fire is a different matter, and this can be - and often is disastrous, resulting in serious damage to the locomotive. For that reason alone there should actually be some kind of an early indication of smokebox fire and extreme temperature. Melting steam delivery pipe plus a lot of smoke of the wrong kind serves as such an indicator... Best wishes from Tokyo, Zubi


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