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Discussion Starter #1
Would anyone have a copy of timing instructions or tips for Walscheart
valves they could link to or email me?

Old kit instructions or such would be very helpful. I am trying to time an Aristo Mikado.

I've read what I can find on the net and watched the animations. I think I have a better clue but could sure use the added help.

Thanks

Andre'
 

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Look on the following website. http://www.roundhouse-eng.com/ then on the left of the page click on TECHNICAL then click on VALVE GEAR then scroll down to the CLICK HERE, this will give you some good information on the setup of a simplified Walshaerts valve gear.
I used it on with my Kit Lady Anne and found it helpful. I had some problems to start but once I had the return cranks at 90 degrees to each other it was just a matter of adjusting the slide valves for the best running in both directions. I use a compressor to run the drive gear whilst I made the adjustments.
I hope this helps
Dave
 

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Andre......if that engine is under warranty I suggest sending it back to Navin at Aristo-Craft.
Wrap it in 5 or 6 towels and sent it back. There is no good documentation available and Navin will set it up and send it back. Your cost is the 40 bucks to get it there. You have been fighting that engine too long. Good Luck.........
 

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If what you have was a kit, then the setting up of the return crank is critical.(see the diagram on the Roundhouse Website) This is where I had all my trouble,
When I would connect up the air, the motion would turn a small amount and lock up. If you have this problem then the return crank is what you need to look at. I actually had one side connected 180 degrees out of whack. Once I realised it and put it right the motion ran, then it was just a matter of adjusting the valve timing at the slides to get really smooth operation.
Take a good look at your setup and ensure these return cranks are leading the drive cranks by 90 degrees.
Regards
Dave
 

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Discussion Starter #5
Re: Timing Errors

After working 96+ hrs a week for most of May I got a weekend off and
managed to get to the train room this afternoon.

I reread the timing tips posted elsewhere and reexamined the Mikado.
On the Aristo forum the main batch of tips for adjustment were
"recalled" by the poster and for good reason. His measurement points
were fixed and were unchangeable by the adjustments. He had the
revelation in the shower and its true.

I decided to start from the valve and piston assys free and
unconnected to any other linkages. Measured the limits of travel,
subtracted, divided by two and added to the minimal travel
measurement. Did that for all four assys.

Then placed the Mikado in null position with reversing linkage
centered. I then set each valve assy to the computed measurement.
Did the same for the pistons with wheels set for each side's 6 0'clock
position.

Turned on the compressor and it ran!!! Was better than anything I had
achieved prior with out doing any tweaking. I attempted to tune it
but kept having the adjustment float away. Remembered someone saying
to make sure no water or oil was in the valves and piston assys so I
turned it wide open and sure enough it blew a bit of water and some
oil out the exhaust tube. I ran a pipe cleaner down the fitting as
far as I could and soaked up a bit more oil.

I turn the throttle valve down low and was able to tune it to a pretty
smooth rotation. There was just a wee bit of a slowdown in one spot
but it wouldn't run at all in reverse. It would get about three
quarters around then stop. So I tuned it for reverse and can get it
almost a bit smoother there but there is a substantial slowdown in
forward.....Sigh.

I'm going to try for a medium spot but I've had it for this evening.

Andre'
 

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You may want to take a look at Steamboating 101 on this web page: http://www.steamboating.net/

I once had a one of Beckman's steamboats and found the information in Steamboation 101 most helpful in understanding and seting the timing for the two cylinder compound engine in my steamboat.

While there are several types of valve gear, the basics of timing are pretty much the same.

DAYoung
 
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