When the engine is fully warmed up the noise almost goes away! We have pulled the motor and dis-assembled, all wrist pins are a little loose but #3 isnt any worse than the other 3.Also all rod bearings look good, and the main bearings on each side of the #3 rod look ok. All pistons mic to be standard size. Are there any odd causes for this type of noise in this year model motor? Please HELP!!!
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1999 GMC Sonoma Question: I have a 1999 Gmc s-15 sonoma with a mild engine knock on cyl #3
Answer #1Hyedegha July 17, 2012, 17:54Technician
Interesting one...did you use oe parts for rebuild or aftermarket?
ReplyYoda1187, July 17, 2012, 19:16Rookie
Haven't rebuilt, just tore down to check valves,guides,pistons,rings,etc.
Answer #2pushrod July 17, 2012, 18:26Master
Why do you say #3 is the problem? How did you test,pull
Plug wire while running? Or something else.
1st answer ask about a rebuild,i missed that part.
ReplyYoda1187, July 17, 2012, 19:20Rookie
Pulled plug wire also stethoscope test its Def coming from 3 no rebuilde yet just diagnosis at this poi.
Replypushrod, July 17, 2012, 23:59Master
This is a puzzle,i have been doing this a long time.Most noise gets worse in a warm engine.
I know a machinest/motor builder, been doing this a long time too.I'll ask this wizzard and get back
if can help.Something is expanding and then fits better.