Kohler Knocking

[Anonymous Poster]

Jrlichina, a new rod was used, and the crank was mic'd during the rebuild and found to be within the specs. Problem is, I've since tossed my sheet of specs, and couldn't remember the website where I found them. Thanks for the website, Justaplain! (Note to self - keep better records!). I didn't want to plastiguage the rod, as the instructions that came with it said not to reuse the posi-lok nuts.

After some initial looks, I'm agreeing with Norm, something is loose inside, and also sounds like it. Going to tear into it tonight, if I get a chance. And wouldn't you know it - it comes at a time when we are supposed to get 4-7" of snow!! Murphy is alive and well!

Thanks, all, and I'll be sure to post the results!

Jeff

 

[CamshaftLF]

Also make sure that the con-rod oil holes are facing the right dir, if I remember right the holes face the intake side of the block. If it has a splasher on the bottom of the rod cap. If you have a internel oil pump disregard the first part.

Cam in Pa.

 

[Anonymous Poster]

Well, got it taken apart ... flywheel wasn't loose, neither was the pulley. Drained the oil, it didn't look bad, no chunks of metal or foreign objects. There was some "streaking" in the oil when I dragged my finger through it, I attribute this to the rings wearing in. Pulled the head off, no scratches inside the cylinder. Everything looked OK inside, oil hole in the rod cap facing the correct way, looks like oil's been getting splashed up real well. The nuts on the rod cap were not loose (glad we weren't betting men!!), so I pulled it off. Inside of the cap looks good, no major scratches except for one faint wear line in it. Is this normal? The cam end play is within spec, I didn't check the crank end yet.

I'm going to mic the crank journal tomorrow. I guess my question now is, if the journal is in spec, what should I look for next? I'm kinda stumped here. I figured the rod is good since it was new. Maybe it could very well be piston slap? I've had 5W-30 oil in it, I figured I should be OK there.

Thanks for the help!

Jeff

 

[BillyP]

Just a thought but could it be crankshaft end-play?

 

[bgott]

Mitsubishi 3.0s in Chryslers used to have a bad habit of dropping valve guides. They would knock like a booger. Maybe?

 

[Anonymous Poster]

I've been out of town for a few days, haven't had a chance to check things out, but hopefully I will tonight. Thankfully, the 7" of snow that was forecasted for Friday night never materialized!!

I was also going to plastiguage the rod/crank if the crank checks out OK. If I do this, should I torque the posi-lok rod bolts to 260 in-lb or to 200 in-lb? The directions that came with it stated 260 in-lb and not to reuse them, I've found specs that state you can reuse them with a torque of 200, and I've had some DIY'ers say torque it down to 265-270 in-lbs.

I'm also going to check the crank end play. It sure doesn't seem to move more than .010", and is pretty hard to do at that. Spec on it is .003-.020", seems pretty liberal. The rod has about .010-.012" end play on the crank.

Thanks for the help, and I'll be sure to post the results.

Jeff

 

[normde2001]

Jeff, I think I would purchase a new set of standard rod cap nuts to use just for the plasti-guage test. You didn't say if you got a new wrist pin, but is the piston "snug but free" on the rod, (no side to side rocking play), also any rocking play at rod and crank connection, (plastiguage test)? Any vertical marks or scratches on the piston skirt denoting piston slap? Strange, you would have thought something would have jumped out at you on teardown.

 

[Anonymous Poster]

I was wondering if anything would show on the piston if this was piston slap - didn't really know what to look for there. But it looked good, no marks. Haven't checked the wrist pin connection yet, I'll do that. One question I forgot to ask - now that I've removed the piston, do I need to put new rings on it, and let it re-seat itself? Or will the same ones (installed at the rebuild) still be good to go?

Thanks!

 

[bgott]

You can use the same rings. Rings can be cracked and break in the bore but you have to drive them out past the cylinder ridge with out cutting it down first if it has one and generally abuse them.

 

[normde2001]

Those rings should be ok as long as no damage in disassembly, etc. By the way, did you check the end gap on the rings before assembly, according to specs? (Put rings into cylinder minus piston and measure gap with feeler guage). Too much gap means rings don't compress enough, and can cause piston slap.