rear main bearing seal fused in place

[alderan33]

I have the engine out of my 72 C10. It's a 350. I am freshening it up with a timing chain and oil pump, seals, freeze plugs, etc.. I am trying to change the rear main bearing seal. I removed the cap and after several minutes of gentle prying was able to remove upper piece. It was REALLY on there. The lower piece, however, seems to be securely fused in place. I have tapped it carefully but it will not move. I don't want to further degrade its structural integrity by bludgeoning it. I believe this is the original motor so it has been in place since the factory. Am I going to have to remove the crank to replace the lower part of the seal? I don't have the money for another motor or even a longblock. Any ideas would be most appreciated.

[chevmn]

Originally Posted by alderan33

I have the engine out of my 72 C10. It's a 350. I am freshening it up with a timing chain and oil pump, seals, freeze plugs, etc.. I am trying to change the rear main bearing seal. I removed the cap and after several minutes of gentle prying was able to remove upper piece. It was REALLY on there. The lower piece, however, seems to be securely fused in place. I have tapped it carefully but it will not move. I don't want to further degrade its structural integrity by bludgeoning it. I believe this is the original motor so it has been in place since the factory. Am I going to have to remove the crank to replace the lower part of the seal? I don't have the money for another motor or even a longblock. Any ideas would be most appreciated.

When you refer to the "lower piece" are you referring to the half that is on the rear main cap, or the piece on the block side? Might have a look at the thread I posted yesterday, as I was having same issue on the half that is between block and crank.

[Accelo]

Sometimes we have to go backwards to move forward. I had to deal with one that was glued in one time. I couldn't think of a reason for that but evidently the builder thought it was a good idea. I would loosen the main caps and see if I could get it out that way. With the crank loose you have less chance of damaging it. Once you get a portion loose you may be able to pull it loose from the groove. Shoving it around requires it all to move at one time. Sounds unlikely given the description you have given of the seal in the cap.
Best of luck

[HO455]

If it is the main cap try heating the cap then putting ice on the bearing half. Soft heat like toaster oven or propane torch, no oxy/acc torches. Too easy to overheat that way. Don't heat the cap more than 200 to 250 degrees.

If it is in the block set the block under a 500 watt quartz light or two, or put it in direct sunlight, (If you're lucky enough ) to warm the block then try putting some dry ice on the bearing half to get it to contract and break the bond holding it.

[alderan33]

Thanks guys. I will try your suggestions this weekend.

[70STOVEBOLT]

See this thread for additional info:

https://67-72chevytrucks.com/vboard/...d.php?t=851576

[chevmn]

After getting mine all out, I think fabricating a tool out of a softer metal might help, and someone mentioned using a nylon drift as well. We ended up using a piece of square keystock being careful to not damage the seal surface on the crank. A piece of square brass might be ideal, but not sure where one might find such. I recently found a swap meet vendor who had some pieces of brass, but nothing I had would fit the bill on this.

[HO455]

I'd order it from McMaster Carr.

https://www.mcmaster.com/products/br...s-square-stock

I apologize for my earlier post I thought you bearings were stuck in place. I'm glad you got the seal removed.

[chevmn]

Originally Posted by HO455

I'd order it from McMaster Carr.

https://www.mcmaster.com/products/br...s-square-stock

I apologize for my earlier post I thought you bearings were stuck in place. I'm glad you got the seal removed.

There were two of us having similar or maybe the same issue. I finally solved my issue, not sure on this OP and if he was able to resolve. Always good to post result and what ultimately resolved, or any new ideas.