Need help with Engine Knock

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Got a good deal on a sweet FJ62. ZERO rust 90K and 6,000 mile on a complete engine rebuild. Here's the deal, the time (12 months) ran out on the warrenty for the rebuild and the engine developed a knock. Not a ping, tap or click but a deep low knock below the head sound like #2 or #3. previous Owner thinks it may be a piston skert or piston pin. Do you guys have any ideas what i should check before I take it to the pros.

Can you pull a piston while engine is in the truck?
 

60wag

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The easiest thing to check are the rod bearing. Remove the oil pan and you'll have a clear view of the whole bottom end of the motor. Remove one rod cap at a time and examine the rod bearings. You can also wiggle the detached rod to feel the condition of the wristpin fit. If one feels different than the rest, you've found the problem. Also note the installed position of the rod bearings - maybe someone got a pair in wrong and that led to the knock.


You can pull the pistons with the head off and the block still in the truck.
 

John McVicker

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Got a good deal on a sweet FJ62. ZERO rust 90K and 6,000 mile on a complete engine rebuild. Here's the deal, the time (12 months) ran out on the warrenty for the rebuild and the engine developed a knock. Not a ping, tap or click but a deep low knock below the head sound like #2 or #3. previous Owner thinks it may be a piston skert or piston pin. Do you guys have any ideas what i should check before I take it to the pros.

Can you pull a piston while engine is in the truck?

Yes, you can pull a piston while still in the truck. I have NOT done this. But from what I gather, you go in from the bottom end & remove from the top. Which of course means you remove the head. All in all a complicated & time consuming procedure,

HTH, John
 
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you can narrow things down a bit if it is a rod knock. pull the spark plug wires off of the suspect cylinders one at a time while the truck is running. if the noise goes away, or gets quieter, you've at least isolated the offending cylinder. caveat; if it is a rod knock, if it's really bad, the above may not work.

if you do go so far as to pull the oil pan, i'd also retorque and/or check the main bearings as well. check thrust bearing/washer play as well since you're in there.

you can pull a piston from the top provided a ridge hasn't built up and provided the rebuilder reamed the ridge during the rebuild. if the have the head off and can feel a ridge at the top of the cylinder, you won't be able to get the piston out without reaming the ridge, which gets metal everywhere.

good luck and keep us posted...hopefully it's nothing too catastrophic.
 

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