fj60 newbie here, video of engine knock/tap. any help pinpointing appreciated

zia

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You can use plastigage to check clearance
am I able to use plastigage without new bearings? or should i take one of other cylinder bearings and put on 1st cylinder then use plastigage to determine what size I need?
 

zia

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to everybody, you have been incredible help. I am very fortunate to be part of this community
 
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I wouldn't bother with plastigauge in your situation, Go with the standard size bearings . Remember this is not a 100% definite fix, but it could be ok for years. depends on the level of scoring on the crank.
 

zia

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ok guys, I have replaced the bearings and wanted to hear your input on how engine sounds. I am hard of hearing and I don't really know what fj62 engine usually sound like. I can hear maybe one of accessory(ac compressor, alternator or PS) whining a bit.

 
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It sounds a lot better than it did. It does still sound like you’ve got a knock as @pithicus noted. When you put in the new bearing did you check the clearance?

Also what weight oil are you running?
 

zia

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I use 10w-30. I also will recheck the rods again, I do recall one of rods had side to side play. would that cause slight knock? or only up and down?
 
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Try a heavier oil. Rod knocks usually get worse when the engine warms up btw.
a quick hard push on the throttle from idle to about 1500 rpm can sometimes make the knock clearer to hear.

Up and down movement is the thing to worry about.
 
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I thought about this some more and while the sound does sound better its still there and that can be problematic. Did you plastic gage the new bearing to verify clearance? Engines are rotating masses with a lot of energy and the only gap you want on the bearing is enough to support the film of oil that the rod end or crank basically floats on. If the gap is too big and you still have rod movement away from and towards the crank journal you will effectively hammer things back into a worse condition and be right back where you started.

You can try a thicker oil and if things quiet down to no knock then you might be ok for a little while...but I'd still want to get in there and figure out if I had too much bearing clearance or play somewhere else.

There are other noises in the video that could be air or exhaust leaks...but right at the end when you roll on the gas there is a deep rumble that sounds like internal sloppiness.
 

OSS

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There were times (like 20 to 30 years ago) when my engine didn’t sound good. Occasionally heard knocking sounds at idle.
It never amounted to anything. 300,000 miles on the odometer and it still ran fine (and quiet). The knocking sound wasn’t caused by a bad bearing but more likely an occasional mis fire or uneven compression or just lack of a tune up or hot idling that caused it to shake a bit and bang metal together in the thrust clearance direction.
 

zia

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i took off the oil pan again and took a look around, everything looks good except for 3rd cylinder rod which have side to side play but no up and down play. I am going to disassemble the 1st cylinder and measure the gap
 
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i took off the oil pan again and took a look around, everything looks good except for 3rd cylinder rod which have side to side play but no up and down play. I am going to disassemble the 1st cylinder and measure the gap
Did you replace all the bearings?
 
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At some point, you should check your engine oil pressure with a real gauge (not the dash gauge). I would hope you would see 20 psi or more at hot idle. If you see less than 10 psi at hot idle, you may still have this (or other) bearing issues. Cold/startup PSI could be as high as 60 psi, which is fine/normal.

I spun a bearing like you did, but mine was on a '58 gas Massey Ferguson tractor. I polished the crank (it was still very sound) and installed new bearings (on just that one cylinder - the rest were fine, per Plastigage), and it has run 10 more years without a whimper. The cause of my bearing failure was the oil bypass valve being stuck open with varnish and the engine had been run for years with very little oil pressure. When I freed the bypass valve and replaced the bearings, I now have excellent oil pressure.

Anyway - the takeaway is that your engine oil pressure tells you a lot about the bearing health of your engine. Your compression numbers are just fine for 7000', BTW.
 

zia

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Hey guys, wanted to update you all on what I found. After a couple of min running the engine with new bearings, I let it cool off overnight and pulled the oil pan. At first look around, everything looked good. Then I gave it a good second look, the first cyl rod still got up and down play! Much better than before but there’s too much play still and must be where the knock is coming from. So I guess i will need to measure it with plastigauge and buy correct oversized bearing for the first cyl.

Again thank you guys for teaching me so much and pointing me toward solutions!
 

3_puppies

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ok guys, I have replaced the bearings and wanted to hear your input on how engine sounds. I am hard of hearing and I don't really know what fj62 engine usually sound like. I can hear maybe one of accessory(ac compressor, alternator or PS) whining a bit.


i see a 3FE ?

NOT a 2F in a FJ60

am i correct @Seth S ?

@3_puppies ??



i see a spun rod bearing for sure !

all this REVVING i killing any chance of Saving this 3FE ?

STOP NOW !


he says 62 series in this post
it is a 3FE
 

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