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View Full Version : piston slap??



vancem3m3
05-01-2009, 05:25 PM
well i thought i spun another bearing ...turns out i did not.. though they did have signs of wear i replaced them put the motor back together and back ect. i still have that tapping sound so i thouhgt valvetrain that not it ..the sound is lower i even started it without the valve cover on everything is good im thinking drive it till it fucking breaks but first can anyone tell me what the noise could be??

tdurr
05-01-2009, 05:27 PM
thicker oil.
try that.

dorin48
05-01-2009, 06:36 PM
well i thought i spun another bearing ...turns out i did not.. though they did have signs of wear i replaced them put the motor back together and back ect. i still have that tapping sound so i thouhgt valvetrain that not it ..the sound is lower i even started it without the valve cover on everything is good im thinking drive it till it fucking breaks but first can anyone tell me what the noise could be??

Can't tell where the noise is coming from with a broom handle or anything? Did you mic the cylinder walls while it was torn down? My educated guess at this point is a failing wrist pin. If this is true it will make a tapping noise from the middle of the block, loudest on the failing cylinder obviously. I asked about the cylinder walls because when they start to fail the piston will begin eating into the sleeve. If this is whats wrong by the time it goes pop you may not be able to bore the block out large enough to fix it. You'll need new sleeves or a short block. Food for though since there isnt a real way to know at this point.

WANTED
05-01-2009, 07:40 PM
How in depth of a tear down did you do? Did you check both the rod bearings as well as the crank and thrust bearings? Did you check the see if perhaps the valves were coming in contact with the pistons? how did the cylinder walls look? Could you have possibly stretched or bent a rod? Could also be a wrist pin as suggested above. Hell, could also be that something is simply loose.