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Be careful polishing your carbs

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vping

vping

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I have this cleanliness thing going and can't help but clean every nut & bolt before I put it back on my car. (doc says I'll be better real soon /ubbthreads/images/graemlins/crazyeyes.gif)

I decided to polish my air chambers and boy do they look good. Problem is I overheated them and now the piston won't go back it.

I spent about an hour honing the inside of the air chamber last night and the piston slides in & out ok, but not sure of what damage I have done.

I would not recommend using a high speed polishing wheel and would only do them by hand if you wanted this look.

Live & learn.
 
keep an eye on that carb if you find you're having trouble.

Those are a very close machined match and I'd think honing might make them too far gone.

Try dropping both pistons with the carbs installed and the engine off at the same time and make sure that they both fall at the same rate. Hopefully the honed one doesn't drop a lot faster than the other one.

Usually the damage done is that the dashpot cover becomes 'egg-shaped' and you can tap it with a rubber mallet to get it back into 'round'

Good luck - sorry about your misfortune.
 
you can get new dashpot covers cheap if you need one...I've got a bunch kicking around. Try the dropping test as Jim described, check to make sure the needle is not bent at all, and make sure that groove than the piston rides on is clean.
 
Funny you should mention the rubber mallet. I notice it was only one spot I must have heated too much. Could not get the piston in at all. Found the high spot & only concentrated there. I tried the mallet but was afraid I might do more damage so I started sanding with 1000. Once the piston was really tight but I could get it in I worked it with some oil and found exactly where the spot was. Was a spot about 1/8" tall by 1/2" wide. Once the piston slid easier I worked the piston with the cover back & forth with oil until it felt "normal" again.

They seem to fall at the same rate but I have a few more things to do before I can finally start her back up after the rocker fiasco.

Replace gas lines, reconnect fule pump wires, readjust valves and put the valve cover back on. I think that's it and we'll see how it goes.

I had the carbs off and am pretty sure how it all went back. I added a new heat shield and springs while it was apart but I think I got all the cable right.

If the heat does not kill me later, I'll bang it out. I'm scheduled for an inspection tomorrow am so I gotta nail this down.
 
Hay, you've had our inspection and are doing just fine.
 
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