Thread: Should I replace my pistons?
01-25-2009, 08:40 PM #1
- Join Date
- May 2005
Should I replace my pistons?
All 3 of my pistons measure 3.9330".
The new spec is 3.9350-3.9360.
The limit is 3.9290.
Piston wall clearance is .0037, .0037 & .0036". (#1,#2,#3)
The new spec is .0009-.0022.
The limit is .0039.
Cylinder taper is .0001" in all 3 cylinders.
Taper limit is .0011.
Cylinder roundness is .0002" in all 3 cylinders.
Cylinder roundness limit is .0006.
All above measurements were taken at the positions specified in the teardown manual.
Can I just go with a re-hone, and new rings? Or should I go with a re-hone and new pistons & rings? Or should I have the cylinders bored out 1mm over with new pistons and rings? 170 hours on the motor.
01-25-2009, 08:48 PM #2
well if the motor has 170 hours on it I dont think its worn that much, unless those hours where hell.
01-25-2009, 09:46 PM #3
I would go to the oversize pistons!!
01-25-2009, 09:48 PM #4
01-25-2009, 10:03 PM #5
I was just making a suggestion on the pistons. 170 hours on stock bores. From his measurements everything is borderline worn out. The logical thing to do would be to go to the Factory oversize pistons and bore the block.
01-25-2009, 10:05 PM #6
It will cost you a set of pistons and rings to find out, if you should have bored it. You can bore it next time!!! Just kidding you don't want this thing to come apart and ruin the entire engine. Always lean on the safe side if there is doubt.
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