[A1Judge]

OK, the infamous rear main leak and how to plan not to fail???

What is the best solution to this when assembling a new motor? Has anyone tried the Viton seal from BOP?

I will be assembling a new motor soon and want to plan this so I don't get any leaks! So what is everyone doing with this?

Thanks

Don

[A1Judge]

OK, the infamous rear main leak and how to plan not to fail???

What is the best solution to this when assembling a new motor? Has anyone tried the Viton seal from BOP?

I will be assembling a new motor soon and want to plan this so I don't get any leaks! So what is everyone doing with this?

Thanks

Don

[RPM]

I assembled my 428 recently with a rope seal and now it leaks. I am now waiting for the BOP seal and will put that in. The rope I installed did work fine for a while and then after I had the car on the highway for a 100 mile trip it started leaking. The leak has gotten progressively worse. Using the old asbestos ropes I never had a problem with but these fiberglass ropes suck. My recommendation would be to use the BOP seal. I also think that there is enough tolerance variation in the machining of the rope recess in the block and the placement of the serrations on the crank to account for the wide differences in how these marginal (rope and Caddy) seals work.

[This message has been edited by RPM (edited 04-25-2001).]

[MitchGM]

My rear seal was leaking on my 428 as well. Two years ago, I took the ST-300 tranny out and installed a T400. At that time, a friend of mine helped me do the job. He bought some kind of rear seal for the engine. I can't remember what he used. I have to ask him. He bought it from an old old supplier where we live. The damn thing hasn't leaked in 2 years. I check periodically. I take the tranny inspection cover off. Still no signs of leaking.

[Old Man Taylor]

Get the BOP seal. It is available now for the 400, and the large journal seal will be available again soon. Order the one you need.

[tom s]

as OMT said,get the BOP seal,I put one in my 3in main V motor,has 11 dyno pulls and over 300 miles on it now with no leak.Tom

[Bob Kazian]

There is a guy that has posted on the "GTO Mailing List" that he recently installed the now available BOP seal in a 400 engine and he has an oil leak.

He reported that the lip of the seal rode on the serrations on the crankshaft, which he didn't think was correct, but that BOP told him to go with it.

Does the BOP seal ride on the serrations? That would seem to me to not be the best for sealing.

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Bob Kazian
Greer, SC
bobgoat67@aol.com

[Tomo]

Had a rope seal in my 455... leaked very little. Got smart and installed a caddalac rear main vitron seal ( per an article in Hi Po Pontiac magazine.... leaks like crazy!!!!!
tom

[Old Man Taylor]

I have been told that in some cases the seals might ride on the crank serations, but that if it is an old crank (not one of the new ones) it is not a problem. I have not heard of any 400 seals leaking. The last time I spoke with BOP they were aware of at least 300 small journal seals that had been installed, and they had no input of any of them leaking.

[Wade Congdon]

Hello,

To date BOP has shipped over 700 seals and estimate around 300 in use based on the feedback we have received. So far we have received only one negative feedback, this from the gentleman that Bob mentioned above. From his description the seal doesnÂ’t leak at all at idle, but drips if the motor is held at 3500 rpm. Assuming the installation was performed correctly, several possible causes may include, an oversized seal groove diameter (we have seen some variation from the factory), too much end gap compression, debris on the sealing area, or possibly a damaged or defective seal. We have contacted this individual and expressed our sympathies regarding his leak. We offered to refund his money and replace the seal free of charge if he wishes to do so.

For the record this gentleman did call about the serrations late one night and we did advise him to go ahead with the install. As far as the seal riding on the serrations, we did originally design it to miss them, however we have discovered a large discrepancy in the placement of the serrations from the factory. Let me stress that even though we tried to miss the serrations, it is not mandatory to do so. Many of the aftermarket seals for other brands ride on the serrations with no problems. In addition, we have had numerous reports of people installing them on the serrations with no problems, with some of the prototypes as long as 8 months and 5000 miles ago. We did originally advertise the seal avoided the serrations and apologize for any confusion this may have caused. Now the ESP cranks are another issue. I spoke with JBP about them when they first came in, and he said the serrations were raised up off the crank about .002" He also stated that the cranks that they sold they were polishing this area just to be safe. When we learned of the potential issue, we took the precaution of making the same suggestion in our latest instructions. Our recommendation would be to remove a thousandth or two at the very most to bring the diameter in line with the rest of the seal area and remove any sharp edges. Remember most stock cranks have had a rope riding on them for 30 years to smooth the serrations. Depending on the groove diameter, the seal will have .020" to .040" of engagement on the diameter so removing a few thousandths won't hurt anything. For the latest instructions see the link below. If you have any questions please feel free to call or email anytime.

Thank You,
Wade Congdon - BOP Engineering

http://www.bopengineering.com/main_seals_install.htm



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Wade Congdon - BOP Engineering
www.bopengineering.com
"If you can turn left you're going too slow"

[Gooatee]

I ordered my BOP seal today and can't wait to try it! I will make sure I follow the directions to the Tee! I have never had any luck with the ropes!

[A1Judge]

Well I ordered a BOP seal yesterday and will use it in the rebuild this summer.

Don

[MitchGM]

Whats the going price for a BOP seal?

[MoJo]

$29.99 for Both sizes

[MoJo]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by MoJo:
$29.99 Each - Both sizes <HR></BLOCKQUOTE>

[Guy Mazza]

I'm no expert engine builder, but I have always assembled my own race & street engines. I have always used the rope seal & never had a rope seal leak, using the same installation procedure I have used on every Pontiac motor. I am sure the BOP seal is a great product, but still curious why so many enthusiasts are havin' a prob w/ the rope seal deal???

[Wade Congdon]

Guy,
In addition to leakage from rope type seals in general, the mandated removal of asbestos from the factory type rope seals, has increased leakage dramatically. Many engine builders will no longer warranty their engines against leakage. These new rope seals can be identified by a bright white center core as opposed to the brownish colored old seals. I noticed in your bio that you look up to Jim Hand, ironically he is the one to bring this problem to the public realm.

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Wade Congdon - BOP Engineering
www.bopengineering.com
"If you can turn left you're going too slow"

[Old Man Taylor]

Jim Hand mailed me a horror story he had with a brand new seal. It seems the new ones have a fiberglass center and they shread. If you can get any old rope seals they are probably good, but how will you know? I also build my own engines and also never had a problem - until the 428 in my GTO.

[Gach]

God, I've built many many motor's using the rope seal, and have never had a problem with one leaking. I don't think just because one guy had a problem, that all of a sudden, it's a major problem.You can buy the Caddy seal from NAPA, for 13.00 bucks, that fits 455's only.

I've also never heard of an engine builder who won't warranty their engines against leakage.Who they hell would buy a motor or have one built, from a guy who won't warranty against leakage.

[J.C.you]

Anybody used the 460 ford seal with 400? I have had good results with several motors built.

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