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Cleaning exhaust valves..how difficult is the removal?


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emerckx53

 
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Cleaning exhaust valves..how difficult is the removal?

Sun Oct 21, 2007 6:32 pm » Post: #1 » Download Post

Mr. Gallant was kind enough to recommend removal and cleaning of the RC valves...I am sure mine have never been cleaned as it is a 93. I took a peek inside the exhaust ports yesterday..newbie question coming!

a. Are the valves visible through the port? what I saw was what I assumed was the RC valves..flat 2 holes etc? was that them? I know they can be located outside the barrel as well....there was a decent amount of carbon built up on them although I do not know what normal is..

b. The exhaust port bridge had a fair amount of carbon as well...the piston wall on the exhaust side was light brown right at the bridge and looked good.

c. What level of difficulty is there in the removal?

thanks n advance

Michael
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Andy
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Sun Oct 21, 2007 11:18 pm » Post: #2 » Download Post

Not a great deal you can do about the exhaust port itself without removing the barrel, but you can remove the Valves. They may be a bit hard to extract if they've not been out before though.

Make sure the piston is at TDC before you try to extract the RC Valve shaft to stop them dropping into awkward places!!! Very Happy
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emerckx53

 
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Sun Oct 21, 2007 11:50 pm » Post: #3 » Download Post

Good point Andy...BUT, without giving me a tutorial...how do they come out? anywhere I can go to see the step by step or is it that easy? Thanks-

Michael
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Canuck13

 
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Mon Oct 22, 2007 8:53 am » Post: #4 » Download Post

get yourself one of the tyga tools for pulling the valve shaft. Makes the job a lot easier. Oh and dont forget the nut/shaft is threaded left hand. I find a wire wheel on the grinder an easy way to clean them up.
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k3

 
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Mon Oct 22, 2007 9:01 am » Post: #5 » Download Post

i had read a method here without the special tool to pull out the shaft, by stacking washers one at a time, threading the nut in each washer and it will come out.
and as Andy says what is the best position of the piston to avoid the valves from falling inside the barrel? and how would you know if the position is in right position is it visible outside the exhaust? anyone pls.
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Mon Oct 22, 2007 11:55 am » Post: #6 » Download Post

Well you have to have the expansion chambers off to get the RC Valve flaps out, so you can see when the piston is covering the exhaust ports by looking up through the exhaust manifold.

I don't use a tool on mine, as they are cleaned fairly regularly and therefore the shaft pulls out easily enough without one. Keeping the shafts and flaps clean, and the cables adjusted properly are paramount for PGM(II, III & IV), RC Valve controller (MC16 & PGM-I), and servo longevity.
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