spun bearing

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Big Blue 84BJ60

Big Blue 84BJ60

Joined
Aug 14, 2007
Threads
28
Messages
396
Location
brampton ont
What causes a spun bearing? please tell all even if unlikley
heres the story I was at highway speed, steped on it no power, oil pressure dropped then cut out, and i tow the truck home.
I just rebuilt the engine, 84 3B 2000km on the rebuild, bearings were not toyota I am hoping they were cheap n thats why they failed.
There was good oil pressure before the problem. Leading up to disaster there was a pulsing in the clutch that varied with engine speed, that stoped after the spun bearing.
The crank surface is fine looks like a mirror i got lucky there, as for the top bearing it is stuck in the rod still 1/3 out 2/3s still in and stuck, the cap bearing came out no problem and the cap surface (were the bottom bearing sits) looks fine no metal build up or scoring

?1 should i replace the rod and cap if the faces are good?
?2 who has the best after market bearings sor, 4 wheel auto or stick with toyota?

:bang: beating my brains in &
I will be so pissed if it was cheap parts (I have this feeling it is)

thanks in advance
Jon
 
Was there metal in the pan? I'm confused - you're saying a bearing DID spin, but the crank is fine and you are apparently able to slide the shells out? Why can't you just push the piston upwards a bit to get it all the crank so the top shell can fall out?

Or are you talking about main bearings?

One thing I noticed when swapping in new bearings in my 3B was that aftermarket mains were all one size, while the OEM bearings come in two sizes (thicknesses). The block is stamped in the corner with which thickness of bearings go in which location which is a nuance of the block's manufacturing. Aftermarket bearings, it seems, try to live in the "just right" region between the two OEM thicknesses but that might not be a good thing. On my truck, for example, the block was stamped to say all but the #4 main bearing should be the thicker kind. I tried to install an aftermarket bearing into the #4 journal but it was very tight and I managed to bend the bearing before I could slide it in. Reused the OEM one in that case. Dunno if thats your problem, but food for thought. :meh:
 
ive tried that, pushing the piston up but the bearing shell is stuck or fused to the rod ill try a couple more things before i have to pull the head to get the piston out
 
Big Blue 84BJ60 said:
ive tried that, pushing the piston up but the bearing shell is stuck or fused to the rod ill try a couple more things before i have to pull the head to get the piston out
Click to expand...

Huh, weird. What happens when you spin the crank by hand? Is the shell fusing the rod and crank together? It doesn't sound like it if the crank is undamaged so you should be able to push the piston up or rotate the crank away.

I'm confused on what the situation is.
 
The crank rotates smoothly, I can see that the top of the bearing is stuck/mashed to the seating surface of the piston rod. The bottom bearing came out with a little fidiling and the cap's mating surface looks good no scratches, grooves or scoring

what are the bearings made of?
 
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Big Blue 84BJ60 said:
The crank rotates smoothly, I can see that the top of the bearing is stuck/mashed to the seating surface of the piston rod. The bottom bearing came out with a little fidiling and the cap's mating surface looks good no scratches, grooves or scoring
Click to expand...

Hmm! Doesn't sound that bad, are you sure you're fixing the right problem or are you just going on our advice in your other thread?

What do the bearing surfaces themselves look like? Are they definitely wrecked? Metal in the pan?
 
oh theres metal in the pan and the bearings themselves are trashed all 8 not just one or 2
the problem is definitly the bearings these new ones have 2000km on the were as the old toyota ones had over 400000km on them and they looked almost new

I think i bought crappy bearings instead of buying from toyota or sor or 4wheel auto I found some from a little shop in toronto and no one could tell me were they came from other than the back room shelf
could it be a bad batch/wrong bearings or is there a gremlin(s) living in my truck?
 
Ah, gotcha.

My vote would be wrong bearings, and or wrong clearances.
 
Did you have the replacement bearings measured in the rods and your crank with a micrometer, they may not have been the correct size [even on one journal]. You should be able to tap the bearing out with a small hammer and pin punch/small screwdriver if it won't pull out by hand using pliers/multigrips. I think you should mic the crank and when you get the bearings mic them when fitted in the conrods before they are fitted to be sure the crank out of round and the bearing assembeled it within tollerances. Also need to clean rocker area, oil galleys and oil pump of all metal shavings. If the replacement bearings were old they were probably lead/tin babbit bearings better than the new alloy stuff. I would use ACL bearings, only MHO. keep us posted, pics would help. cheers
 
you might be looking for another problem... usually bearings get eaten by lack of lubrication. could it be oil pump pickup tube cracked or leaked? or like was said they were all the wrong size. maybe some crap from the rebuild was plugging up the oil gallery and starved it of oil. post up some pics of the bearings they hold the answer as to what destroyed them.
 
oil pump is new no problem there
the crank was within specs I used a micrometer but i didnt use the plasti guage for oil clearance
the only other thing is the truck was started up 2-3 times and shut down due to lack of oil pressure the oil pump lost its prime the bearings might have worn then
thanks guys for all the replies
i'll get some pics of the mangled bearings posted tommorow
 
Big Blue 84BJ60 said:
oil pump is new no problem there
the crank was within specs I used a micrometer but i didnt use the plasti guage for oil clearance
the only other thing is the truck was started up 2-3 times and shut down due to lack of oil pressure the oil pump lost its prime the bearings might have worn then
thanks guys for all the replies
i'll get some pics of the mangled bearings posted tommorow
Click to expand...

Yeah I remember your oil pump threads. I wouldn't worry too much about the lack of prime - I replaced my bearings and lost prime and took 2-3 starts to get it back. I'm passing 3000lm now with no probs. (knock on wood!)
 
did you build it with assembly lube? lubriplate is good stuff i use it. then use whatever means possible to prime the oil galleries. last time i improvised using a plastic jug with screw on lid and a small air pump to pressurize the container which had a hose that went to the oil gallery.. started up and had instant oil pressure. especially important if you have a turbo.
 
I used white lithium grease as assembly lube
Also i noticed my crank shaft mooves back and forth this is bad isn't it
how do i tighten it up or stop the play?

and here are the pics of the bearings
the 6 others look like the bottom pic all worn looking
auto 002.webp
auto 005.webp
auto 001.webp
 
that one that is all black got burned up from lack of lubrication.also look at the backside, totally spun around, lack of lubrication there. ive seen that before, the bearing was practically welded to the rod. you might want to get that rod checked out by a machine shop, it could be damaged from the overheating. maybe they were the wrong bearings, and excessive crush caused them to deform like that, and there was not enough clearance resulting in lubrication not reaching it properly. thats a shame, what a way to kill an engine, after only 2000km.
you should have some end play in the crank, but if its too much youre looking for trouble. you need to measure it with a dial indicator. to adjust it you need to get different thickness of thrust washers...
which brings us to the next question, were the thrust washer installed the right direction? did they fall out? ive seen them fall out before too. ive also seen trannys or clutches blow up, resulting in taking out thrust bearings and crank shafts. you say your clutch was chattering? there could be a connection there. when you push the clutch you are also putting pressure on the thrust bearings.
what a mess you have there.. good luck getting it sorted out.
 
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the rod is fine nothing stuck to the bearing matting surface. The crank is good no out of round or damage, the reason for the bearing bieng stuck was the metal rolled over the sides and got pushed into the oil cavitie/passage in the rod.

what do you mean thrust washer??
the mains have a thust bearing that sits in the middle but no washers I think thoes came on later model 3bs
The crank moves but not much, ill get out the dial indicator magnetic base and see were im at i hope is good, as for the pulse i think that was the bearing starting to go cause after it spun the pulse stoped

i will pull the mains tommorow they'll hopefully look better

but i have a feeling the rod bearings i got were smaller than regular or the wrong ones they dont really measure up to the old ones there off by a little which makes me think they were the wrong ones

i hope its sorted out
thanks again for the replies
keep them comming
 
oh man, I'm hurtin for ya here, you're taking it well, i'd be really upset.

x2 on checking the rod, some bad juju was going on there.

Regarding the crank play, all the newer 3B bearings i found had the thrust washers integrated into the #3 bearing. I could only find one size, so I don't know if or where to get shims or other sizes to take up play. However, I'm a little bit worried - given your evidence of oil starvation and the pulsing you said you felt in the clutch, I think you should pull the main caps for sure and see how your mains bearing look - the thrust washer and bearing could be burned up.
 
Big Blue 84BJ60 said:
but i have a feeling the rod bearings i got were smaller than regular or the wrong ones they dont really measure up to the old ones there off by a little which makes me think they were the wrong ones
Click to expand...

ut oh.

Did it look anything like this? (correct bearing on the right)
attachment.php


SOR kept insisting they sent me the right part until I research it on my own and proved via the EPC that their listings were wrong - they sent me B/2B bearings:
IH8MUD Forums - View Single Post - 3B main/con rod bearing swap pictures!
 
HOARSE S**T!!!!!

armurer man thas what i couldn't figure out they fit but too well there too small and the guy behind the counter insisted they were correct thanks so much man for the pics i wasnt sure cuz the bearings are manged and worn but now i sure they were the wrong ones/size
what are the numbers on the smaller bearing? they look to be the same as mine

as for the main there all being pulled and replaced i have this feeling they will be fine, but i have new main and rod bearings on the way as for the cam bearings they seem to be just fine which is why i think the mains will be fine,but that will be found out tommorow

and for the record i didnt take it all that well lets just say when it happened i lost it (i had just rebuilt this bastard and it does this) so the four letter words flew like the birds

all in all atleast it was parts not my negligence or wrenching

oil flows through the crank shaft then to the bearings correct?
 
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