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

zia

Joined
Apr 6, 2021
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santa fe NM
ok thank you for the FSM link, will be using it. I wanted to update you guys, I dropped the oil pan and touched every cylinder. the first one definitely have a lot more play. the cylinder walls on every cylinder looks good. I will unbolt the first cyl rod bearing nuts after lunch

 

zia

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Apr 6, 2021
Messages
29
Location
santa fe NM
I am working on this for a friend who got this a while ago, said it was never rebuilt.

ok, so I unbolted the bearing nuts and finally was able to get the cap off. my first view was literally two shims of bearings being on top of each other. heres a pic to show what it looked like. how did it come to this? does this mean it was rebuilt and bearings were installed incorrectly that it was torqued when both bearings were on top of each other and then when the bearings slid out to its position, the rod became loose? or it was installed then the edges of bearings broke off and was able to slid into each other?

heres a video of bearings removed, what should I do in regards of polishing etc? I can feel a little of journals on my fingers


9335FAB6-24BD-4BBF-92FB-4FB135801060.jpeg
 
Joined
Mar 4, 2016
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Boulder, Co
Wow... yeah that isn’t suppose to look like that. You may need to have the crank shaft ground and polished. I would definitely suggest new bearings all throughout the crank case. It seems you caught that JUST in time!!
 
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Nov 25, 2014
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Western victoria Australia
You probably should get the crank ground.
However
A friend of mine had a 3b that ran out of oil. The crank had bad scores on one lobe similar to yours. I used emery cloth and spent about an hour smoothing it in an attempt to get him back on the road temporarily. After replacing all the bigend shells it seemed to run ok. That was 10 years ago, and it's still fine.
 
Joined
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Boulder, Co
You probably should get the crank ground.
However
A friend of mine had a 3b that ran out of oil. The crank had bad scores on one lobe similar to yours. I used emery cloth and spent about an hour smoothing it in an attempt to get him back on the road temporarily. After replacing all the bigend shells it seemed to run ok. That was 10 years ago, and it's still fine.
I’ve seen people do the ol’ 400 grit sandpaper and shoestring wrapped around the crank a couple of times trick with great success. Depending on how bad the scoring is you might get away with it like you said.
 

zia

Joined
Apr 6, 2021
Messages
29
Location
santa fe NM
thank you guys! I will try those methods to smooth out the crank.

It is ironic that the hardest part of this whole thing is that I can't figure out what size bearings I need....on the old bearings I cant find any number stamped on it. However the cap on first cylinder crankshaft shows number 3. is that the mark number or no. number? I need both numbers to find correct size on toyota online shop
 
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Nov 25, 2014
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My guess is the engine is original and untouched. It has been run low or out of oil and damaged the bearings. These old engines are surprisingly forgiving. If it was me? I would order the standard original 2f bigend bearings and replace them all, [after smoothing the crank] .All six bearing shell pairs are identical btw. It might go for years, like my friend's 3b. If not, it's not a big expense for the bearing shells.
cheers
 
Joined
Jul 21, 2012
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Rhode Island USA
Usually what happens is the engine runs low on oil, and then the bearing runs out of oil. This causes the bearing shell half to stick to the crankshaft. When this happens, it tears the bearing shells off their locating notches and starts spinning them around inside the connecting rod. Notice how that connecting rod cap is black, when the rest of them are brown? That means that cap got very hot.

Unfortunately this damages the crankshaft and the connecting rod. The proper way to fix this is to remove the crankshaft, have it ground & polished, replace the connecting rod, and then install oversized bearings shells.

You can try just replacing the bearing shells and doing a "hand polish" of the crankshaft if you're desperate. Might last the rest of your life, might only last 5 minutes.
 
Joined
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Western victoria Australia
Use lots of oil on the shells when replacing them. Make sure the scored one is free and not binding when it's torqued up. When you first start it, keep the revs low for a while as it beds in.
Good luck.
 

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