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Old 01-19-2008, 06:25 AM   #1
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Default Pinch too TIGHT!

I have a piston and sleeve that is so tight that even after running in 3/4 a gallon, is so tight that I have to take the engine apart to get it unstuck. Any Ideas? Idle temps for running in has been from 170 to 205.....

The piston keeps getting stuck and when I remove it, it has a sticky film on the sides of the piston, and to get it to start up again, I have to clean the film off the sides of the piston....I've done this 3 times and I'm about to toss it to the side.

thanks
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Old 01-19-2008, 08:18 AM   #2
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Pre-heat the engine with a hairdryer for less pinch....

About the film... what fuel are you using? Maybe worth a try to use another brand fuel?
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Old 01-19-2008, 08:37 AM   #3
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when I use a heat gun, the engine is still to tight to get unstuck after I shut it down. I've tried Sidewinder, RocketScience, and Werks fuel, it doesn't make a difference, it just gets this sticky film on it.

I was thinking about taking the sleeve out and heating it with the heat gun and pushing the piston to the top and letting it cool. after that I would have to heat it again to get it out, but I though maybe it would resize it just a bit....any thoughts on that?
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Old 01-19-2008, 09:05 AM   #4
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dude man, pritty obvious, if it's this tight, put more headshims man
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Old 01-19-2008, 10:36 AM   #5
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run it up to 220- 225F. Does not sound like your fuel is good with that film.
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Old 01-19-2008, 04:15 PM   #6
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Quote:
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dude man, pritty obvious, if it's this tight, put more headshims man
Your kidding, right?
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Old 01-19-2008, 06:05 PM   #7
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it lowers the compression and does not abuse the rod as much. I always add a tenth or two for break in.
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Old 01-20-2008, 03:09 AM   #8
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Your kidding, right?
no i'm not. if this does not fix it, then it's possible that the piston and sleeve is a very bad match, and something went terribly wrong when it was assembled in the factory. might be one of those 1 in 5000 type scenarios.
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Old 01-20-2008, 03:26 AM   #9
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no i'm not. if this does not fix it, then it's possible that the piston and sleeve is a very bad match, and something went terribly wrong when it was assembled in the factory. might be one of those 1 in 5000 type scenarios.
such as my murnand modified 35 plus 31 that god broke in half at the block
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Old 01-20-2008, 03:27 AM   #10
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i was getting off our second straight and then doin a 180 then going into the S curves when a guy in front of me hit a pipe and went under the pipe and i hit him and his bumper hit the head of my car and ripped it backwards
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Old 01-20-2008, 03:07 PM   #11
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I've had the discusion with a fellow racer that siad the same thing about the fuel....I'm going to be running another brand fuel through it after the Chargers/Paitriots game......I'll run 3 tanks in it to test the theory and tear it down and check the pinch/film build up.
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Old 01-20-2008, 04:52 PM   #12
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Old 01-20-2008, 06:06 PM   #13
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still very tight, but no film build up this time......
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Old 01-20-2008, 06:14 PM   #14
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rcfoolz,

what are you using for afterrun oil?

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Old 01-20-2008, 06:19 PM   #15
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I hadn't used any in that engine with the brand new piston and sleeve......It has 7 tanks in it, I was using sidewinder for the first 4 tanks, and then I ran 3 tanks of RocketScience. I couldn't realy tell you true temps due to the ambiant air is cooler then it was with the other fuel.
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