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Discussion Starter #1
Hey guys, I made a STUPID mistake yesterday during a valve adjustment on my RC and had TWO shims in the valve bucket while I turned the motor over...stupid me forgot to check that the old one was stuck underneath. The question is, did I bend a valve or am I am all set? I'm of course quite worried after I figured out what I did. All input appreciated...thanks in advance!
 

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Did it feel like you really had to force it to turn over when you did it by hand? If not then you are probably good. Do you have a leak down tester? I would do that and see if it's sealing good. They are like $40 from harbor freight.
 

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Discussion Starter #5
It did feel hard, but not sure if any harder than normal (left plugs in). Leak down tester is a good idea, I do have one.
 

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Well my leak down tester is junk, so ordered one and have to wait for it to come in :( Until them, anyone else ever do this or have any input? Does anyone know the (OEM) piston-to-valve clearance?
 

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Did you check the gap with the old shim prior to the work?
If so, just fit the old shim & check the gap. if its bigger. Then you've bent the valve. If not. Then its happy days.


inlet clearance = 0.16+- 0.03mm
Outlet clearance =0.31+-0.03mm
 

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Discussion Starter #11
how thick are the shims you had in there? probly be ok considering people dropping in high lift cams with factory pistons.
I think 1.95 and 2.00 mm (would have to check)...so I was probably at around +2mm lift.

Did you check the gap with the old shim prior to the work?
If so, just fit the old shim & check the gap. if its bigger. Then you've bent the valve. If not. Then its happy days.


inlet clearance = 0.16+- 0.03mm
Outlet clearance =0.31+-0.03mm
Thanks, I would have to check my measurements, but I did a leakdown (see below).

On i side note, how did you manage to fit two shims in one bucket?
I was being careless, and had the buckets in and out, in and out, and managed to not notice that the shim was stuck in the bottom of the lifter when I had already placed one in the bucket...DOH!

I was kinda wondering how you missed that. After you put the new shims in, you would normally recheck your valve clearances before buttoning it all up again. Did you just forget to check one of them?
Well, after I buttoned it up, I spun the motor to make sure it was perfectly at TDC. Should have checked clearances first...


Well, I couldn't get a % leakdown with my junk tester (one is ordered and on the way), but I WAS able to successfully pump 100PSI into the cylinder at TDC, and all the noise was from the crankcase area, not a single peep with my ear up to the cans...I THINK it's safe to say I'm good without any noise from the exhaust with the cylinder pumped full of air?
 

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Well, I couldn't get a % leakdown with my junk tester (one is ordered and on the way), but I WAS able to successfully pump 100PSI into the cylinder at TDC, and all the noise was from the crankcase area, not a single peep with my ear up to the cans...I THINK it's safe to say I'm good without any noise from the exhaust with the cylinder pumped full of air?
That's great to here, IMO, and I'm especially glad because I feel partially responsible since I left you hanging! :(
 

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Discussion Starter #13
That's great to here, IMO, and I'm especially glad because I feel partially responsible since I left you hanging! :(
Not at all, Matt! Thanks again for the help! 100% my fault for being careless...I definitely learned my lesson LOL. At least I know I will never do it again.
 
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