OLDS 307 Rear Main Seal

ssn696

Living in the Past
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Corrupted by Chevy, I was surprised to see a rope seal kit is all that is offered for the Olds 307. Not sure this one is bad, but I thought I’d figure out what I’m doing ahead of time.
If anyone is familiar with this job, a detailed write-up would be welcome. Photos too if I could be needy. I don’t want to pull all the caps but I’m not sure it can be done otherwise. The goal less leaks, rather than more...
 

Texas82GP

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Apr 3, 2015
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Corrupted by Chevy, I was surprised to see a rope seal kit is all that is offered for the Olds 307. Not sure this one is bad, but I thought I’d figure out what I’m doing ahead of time.
If anyone is familiar with this job, a detailed write-up would be welcome. Photos too if I could be needy. I don’t want to pull all the caps but I’m not sure it can be done otherwise. The goal less leaks, rather than more...
25 years ago most of the parts stores wanted to sell a rope seal for the 307. I found the correct two piece seal from a local independent store. If I remember correctly, it was a Victor-Reinze (sp?). Maybe they are no longer available but I encourage you to keep looking for the correct seal. Hopefully the Olds gurus will chime in.
 

Texas82GP

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Texas82GP

Just-a-worm
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Spring, Texas

69hurstolds

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Felpro BS6141 Ford 292 NON-Diesel. Or equivalent.

You can use an AMC seal too, BS40612, but it has longer "ears" that would need cutting. The 292 seal doesn't have the long ears.

Or you can use the correct GM "packing" p/n 9772831. Aka rope seal. Oh wait...on second thought, don't. :)
 
Oct 14, 2008
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Melville,Saskatchewan
I have used the Ford 292 seal and the AMC 6 seal with the ears cut off. Supposedly the AMC 360 seal is the same without ears. The 292 seal is an easier fit, the AMC 6 seal fits very tight.
 

ssn696

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Can the neoprene seal be installed with only the rear cap removed? For SBC, there used to be a ‘sneaky Pete’ tool with point and coil you could use to grab and pull on the block half of the old seal. Then soak a piece of rag in solvent and drag it through to clean it out before inching the new seal half in place. Hoping for a similar option that does not require lifting the crank...
 
Oct 14, 2008
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Melville,Saskatchewan
It depends, sometimes the crank needs the mains loosened enough to just get the crank off the seal, had to do that on one. The last Olds 350 I did took 5 minutes to go from rope to Neoprene with the motor out. The rope seal was changed at some point, pulled it out easily with pliers. A sneaky Pete maybe enough to get the old one out, just depends on how mangled it is.
 

Texas82GP

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Apr 3, 2015
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Spring, Texas
Can the neoprene seal be installed with only the rear cap removed? For SBC, there used to be a ‘sneaky Pete’ tool with point and coil you could use to grab and pull on the block half of the old seal. Then soak a piece of rag in solvent and drag it through to clean it out before inching the new seal half in place. Hoping for a similar option that does not require lifting the crank...
When I did it 25 years ago, the engine was out of the car on a stand, upside down and I just pulled the rear main cap. I don't remember it being difficult at all.
 
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