# Wuhu/Bowande A4 Repaired and tuneup



## Charles (Jan 2, 2008)

Bowande A4


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## cocobear1313 (Apr 27, 2012)

Nice video Charles. What were the repairs involved, gaskets and the like? Performs very nice when all is well as mine does. Thanks for the video.
Dave


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## rbednarik (Jan 2, 2008)

Dave,

Valve timing was the biggest item to getting good performance out of the A4. Below is the list of items done to get the performance consistent with 8-10 cars on.

A4 #60007


Re-timed all three cylinders, found all to be out of spec
Outside valve gear was not throwing correctly, causing off-square events.
Center cylinder was affected as well by this
Center cylinder is a real bugger to get right owing to the side-mounted valve between the frames
 
Retimed, the engine runs best with reverser wound back 1.5-2 turns from full forward gear.
 
Repaired cosmetic damage
pulled buffer beam and cowling back into correct shape, pulled dents out of "cod mouth" front door
 
Replaced gas jet with larger one. #6 was used
Original found to be too small (#3) resulting in not enough gas flow at higher steam demand rates.
now will keep 50-60 psi with axle pump on
 
 
New water line connections
Similar in style to the Aster A3 using smaller nuts and threaded fittings for less bulk and ease of use
New lines exit at rear drag beam below footplate, either side of drawbar.
 
Adjusted springing
Can now pull 10 Mk 1 coaches without slipping
 
New bypass valve needle made
Original had slot for screwdriver, very awkward to operate "on-the-fly"
Turned new from brass with same spec taper, threading, etc
left it stick proud by 4mm from frame, drilled halfway through for 1/16 roll pin for handle
 
Now have easy operation, able to be done using one finger at speed. Down to send back to tender, up to put in boiler.
 The Axle Pump is really big for engine and takes some getting used to, but the extra reserve is nice to be able to get the boiler full in a hurry.
 
 
Hope this makes it a little more clear. The engine is great value for money and gives reliable performance that rivals all the old hand manufacturers.

Unfortunately I neglected to take many (or any for that matter!) photos of the water line relocation or new bypass valve needle, but I can certainly scan the sketches if anyone wants.


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## Jerry Barnes (Jan 2, 2008)

It does not inspire one to buy their product.


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## Greg Elmassian (Jan 3, 2008)

It would inspire me to add Charles' services to the cost of the loco when considering purchase.


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## rbednarik (Jan 2, 2008)

With respect, please do not make this exception to be the rule! 

There are many of these engines running quite well, the engine is very well built. As far as I know, despite these corrected items, the A4 was a solid performer prior to being sent for the work previously listed.

Some of the modifications made were at the request of the customer for ease of use more in line with their other engines. 

It was NOT because the components failed to do the required job. Bad operational ergonomics do not mean a design is failed if it still does the job indented! How awkward it is to operate the component is a different story.


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## cocobear1313 (Apr 27, 2012)

Ryan, thanks for the list. I needed to perform the same mods (with the exception of the cosmetic) to mine as well as two others for people I know. The engine IS A GOOD design but the factory needs to spend more time with the details. My experience with this engine has not prevented me to aquire another, which I did but it is a consistent phenomenon. I think Greg hit the nail on the head, go in knowing, you, or someone more experienced may need to do some tweaking to get the best out of this. I am going to try your bigger jet as well as I have found as the weather is getting colder, I am getting more steam critical and additional margin would be desirable. I can pull my 9 Mk1's at scale or higher speeds with an occasional toot on the whistle( I added RC). The last caution to you Ryan is that before returning the loco to the owner, consider replacing the backhead seals as mine have all let go and so have the other peoples mentioned. Inferior gasket material. I have started to experience this on my newer WuHu as well. I can provide you a laser cut set at no charge if you like. The last mod (other than the jet now) is I am planning to add RC to the pump.

Best regards,
David


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## steamtom1 (Jan 2, 2008)

And here is a video of Dave's A4 pulling his 9 Mk1s, plus my 4...


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## steamtom1 (Jan 2, 2008)

And in a blatant attempt to hijack the thread, here is a video of my ancient Pannier, pulling the same rake--and this time it didn't even burst into flames...


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## Greg Elmassian (Jan 3, 2008)

My comment was only meant to communicate that with all the timing issues the unit had, that if I were to buy one, I would consider the extra cost of Charles' "attention" to be added to the total cost of the purchase.

If all cylinders were way out of time and the center cylinder especially difficult, it would appear this would be a prudent course of action.

Greg


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## cocobear1313 (Apr 27, 2012)

As an amusing aside, if you watch Tom's video, you can see steam streaming out of the cab as it had just had the only seal I had not replaced let go. I hadn't replaced it because I would have to remove the whistle servo to get at it and that is a bit of a pain. I removed the servo and put in a new seal last Monday, All is well again. Does demonstrate the available steam however.

Dave


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## R. V. Brunell (Jun 24, 2014)

Colobear, could you be so kind as to post photos of your R/C installation, especially for the whistle? And now the axle pump!

I have been thinking of installing R/C in my A4, but have been puzzling over an arrangement in such a tight space. Since you have already done the job, I'd like to follow in your footsteps.


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## cocobear1313 (Apr 27, 2012)

R.V., next time I am in the basement, I will take some pics. It is yight and you do have to jam stuff in the space available. I also removed a lot of the stuff from under the tender to make room for the receiver and battery.

Dave


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## Charles (Jan 2, 2008)

*A4 rc*

I am sure we posted this awhile ago but here are photos of our installation in an Aster A4. The Bowande engine is similar in setup, but has more room in the cab and less piping to skirt around. 

Aster A4 RC

As Dave said most of the items under the tender need to be removed to gain the access needed. 
https://flic.kr/p/nCoDWs


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## R. V. Brunell (Jun 24, 2014)

Nice job on the Aster. But I'm still interested in seeing the R/C installation on the Wuhu.


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## Joevan (Nov 17, 2009)

Hi Ryan,

I just obtained one of these A4's, It needs some fine tuning as it runs a bit lumpy at the moment. I have built and timed quite a few Aster kits but this one is a bit different. The centre cylinder's valve chest can't be accsesed to check the ports etc. I have obtained a few instruction pics ex factory I think that attemps to show how to time the centre valve. I'm lost a bit in the Chinese translation, there are 2 marks on the valve stem that I assume indicate valve position in the steam chest but the rest is a bit confusing. Since you have already done one of these locos maybe you could give me a few pointers on how to time that valve. I have attached those pics. 

Cheers, Joe


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