Replacing Main bearings while the engine is in the truck.

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Yeah man, those look like crap. How many miles? Think that replacing the front main again will solve your remaining leak?

When I change my oil pan gasket, I think I'll pop a cap to see what my mains look like:eek:
 
Yikes, wonder what the crank looks like

That's what I was thinking ... Well, prolly will be a short-term band-aid. :D

Did you plasti-gauge ?
 
For as worn out as those bearings are there are no marks or scoring on the crank itself. It looks great, I'm pretty fortunate.

There are 178,000 miles on the engine and I have no idea what would have messed them up so bad. With the new bearings in there is no play in the crankshaft while the engine is running so I'm pretty confident that a new timing cover seal should be all I need to have a leak free engine once again.

I should also mention that due to the amount of lift I have with my setup I was able to comfortably due this without putting the truck on a lift. Those with stock setups would probably need to get some wheel ramps to do this.
 
Maybe not frequent enough oil changes ?

Anyway, knowing these beasts, I bet that 2F goes another 178K !

Thanks for the pix !
 
Maybe not frequent enough oil changes ?

Anyway, knowing these beasts, I bet that 2F goes another 178K !

Thanks for the pix !

Yeah, well I hope it at least lasts the summer.
I'm glad I could help, I wish I could have gotten more pictures.
 
I wouldn't worry about the crank. Ige's Nuclearlemon ran for years on a crank that was severely undersized and standard sized bearings with no issues, although she did run straight 50w oil. She's the one who taught me how easy it was to do the bearings without dropping the crank when Romer had her fix his engine.
 
the way those mains look.... i am wondering about the rod bearings ???
 
It really looks like an oil starvation issue. What lead to this problem? Was it knocking?

Lucky your crank survived.
 
Hey STeve, did you just put the original sized bearings back in or did you go 5,10,20 thou over with the replacements???????

I just went with standard sized bearings.

the way those mains look.... i am wondering about the rod bearings ???

Yeah... I probably should have checked them, but I really just want to run this motor for the summer. Then I'm swapping my 6BT in. :grinpimp:

It really looks like an oil starvation issue. What lead to this problem? Was it knocking?

Lucky your crank survived.

No knocking from the engine, I have no idea what could have caused it. Possibly it could have been from the head gasket that was blown. There was a ton of antifreeeze mixed in with the oil.

It actually has a knock coming from the engine now that I have replaced the bearings.
 
There was a ton of antifreeeze mixed in with the oil.

and antifreeze eats bearings... thus, when you lose a head gasket and get coolant in the oil,
ya gotta fix it immediately.

t
 
Ugg..
I just removed my rear bearing cap to replace the rear main seal on my 2F.... and the lower bearing dropped off before I could note it's orientation. See picture. Is the orientation show in the picture correct? I think it is, since I can see the slight outline of the oil groove on the journal... but I thought I would run it by you guys .... since it is obviously something I would rather not botch. The picture in the FSM shows otherwise.
Thanks much in advance!

rearLowerBearing.webp
 
Looking at the groove I would say you have it the way it was installed previously. As to whether that is correct according to the FSM I can't comment.

It should be fine though. The bearing seems to be in great shape.
 
Has anyone done this on a 3fe? I have a similar issue where I can't stop oil from passing the front timing gear seal. I am going to check the bearings but it seems as though I will need to remove the timing gears to get the #1 bearing cap off.
 
Has anyone done this on a 3fe? I have a similar issue where I can't stop oil from passing the front timing gear seal. I am going to check the bearings but it seems as though I will need to remove the timing gears to get the #1 bearing cap off.
Ok the front bearing has four bolts, two in the cap and the bottom two from the gear cover. Now it looks as if the rear cap will not come off without mixing it up with the transmission. I'm willing, my rear main leaks as well, but it might be more bananas than I can handle.

Edit: Got these out of the truck and as expected #1 was badly worn and out of spec. #2 and #3 had minor signs of wear and were barely in spec. #4 is still in the truck. I used plastigauge to check the clearances. Luckily the crankshaft is still shiny and baby smooth. Parts on order. Hopefully this solves my leaky timing cover seal.
 
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Just a quick follow up. These bearings roled right in! A little daunting but definitely doable. I launched into this to solve a problem with oil getting past the front timing cover seal. My theory was that there was too much play/movement in the front bearing and the seal just couldn't keep up. Just a theory, but she was running a steady dribble before and now she is bone dry. Couldn't have done it without mud.
 

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