[Dragncar]

What is it. I bought a BOP for the Whittmore engine but it never made it back to me.
Isn't there some new 'rope" seal that is the hot ticket ?
Also, best pan seal. A buddy of mine uses no gasket, just silicone and his engine is spotless.
I retired my 455 today. It was done so long ago that it has a 460 Ford rear main. Only one available in 1989. I was getting a nickle size spot on the ground after a few hours sitting.
In the 80s there was a gap when the asbestos ropes were no longer available and good vi-ton the same thing.
Thanks for any help.

[mgarblik]

I use the BOP seals exclusively. Personally, I like the 2 piece best. Not because of any leak issues. We take our engines apart frequently and the BOP 1 piece seal really needs 2 people to install. I work by myself and locating the seal, squeezing it together, locating it in the groove all while holding an 80 lb. crankshaft up by myself is difficult. The 2 piece is leak free and a 1 man operation to install. The "Best" brand rope seal is the best I know of if you want to go that route. I can make them leak free as well. But why?, when viton is available?

[Rob B]

I like the BOP 2 piece also. Last year when I went thru the wife's motor, I was accidentally sent the one piece BOP seal. Its worked fine also but does require a little more effort (or paying a little more attention to details) to make it work. There is/was a rope seal out there that people are having good luck with also, its just boils down to your own personal preference.
So I have 2 motors with the 2 piece and 1 with the one piece BOP seal and not a drop of oil out of any of them. All 3 are the 3" seal. I've also used the 3.25" with the same results.

[badgto]

I use a graphite rope seal. Works good for me. Butlers sells it. Made by best gasket part # bga-63825 for 421-455 cranks.

[t money]

Dragcar. Do you mean the caddy seal 3.25 main. Back in the day the 460 ford seal was used on 3’’ mains. I think ???

[chiefbigb]

From what I can see the one piece seal is a uncut 2 piece seal with a double lip. I have used a couple one piece seals with no leakage. A local builder told me he cuts the one piece seal and makes it a 2 piece. I have not tried this but seems like it would work. I hear the one piece design works much better when using a vacume pump.

[BruceWilkie]

BOP 2 piece seal on a street motor.
Fourteen and a half years and not a drop.
I think I'd be comfortable with the new 1 piece seal.

[tom s]

My experience ever since the BOP seal came out is im 50-50 on the 2pc for leaking but 100% good on the 1 pc.Im also 100% with the Best Gasket Co rope seal.The issue I had with the 2 pc is if the seal grove is not concentric they have a high degree to leak.With the BOP seals we always do the tilt test now.Put oil in the engine and tilt the engine back where the oil will go against the seal.FWIW,Tom

[Richie Hoffman]

BOP 1 and 2 piece no problems

[wreckmastr]

I like the BOP 2 piece best

[Mark G]

I like the BOP 2 piece cork gasket fill up a old coffee cup...

[GTOGEORGE]

I’ve used the one piece seal twice and it is flawless!


GTO George

[J GLASGO]

We have used around 10 of the bop 1 piece seals with no leaks. Never used their oil pan gasket, but have bought a couple cars that had them with no leaks either.

[Dragncar]

Originally Posted by t money

Dragcar. Do you mean the caddy seal 3.25 main. Back in the day the 460 ford seal was used on 3’’ mains. I think ???

Yes you are right. Dan told me the 460 seal was used on 400s and the Caddy seal is the one he sent me. Got it backwards.
I did buy a 2 piece BOP and sent it to him, was not in the engine crate I got back.
Looks like its between the one piece BOP and the Best for me.
Note, one other thing I did not get back after Dan died was one of those finned cast valley pans with the old school breather on the rear of it. I forgot to even ask for it, so long ago. maybe I can call his widow and ask her. Nice lady, she remembered me talking to Dan for hours on the phone.

[Dragncar]

Originally Posted by chiefbigb

From what I can see the one piece seal is a uncut 2 piece seal with a double lip. I have used a couple one piece seals with no leakage. A local builder told me he cuts the one piece seal and makes it a 2 piece. I have not tried this but seems like it would work. I hear the one piece design works much better when using a vacume pump.

So the one piece, you "stretch" it over the flywheel flange ? The Caddy seal I have has a large wire in the middle of it, not happening if one piece.
Asking because at this point I have never actually laid my eyes on a BOP or any modern Pontiac rear main seal.
I know it was such a issue in the 80s the SS guys would reuse their old asbestos seals because of availability and the drag a new one on the crank.

[Old Goat Racer]

A couple months ago JR. was putting his motor back together and asked me if I had any of those GM rope seals left. Yeah.
He installed one and the motor is bone dry. I think I have 4-5 left.

[Sirrotica]

The graphite rope seal is what is used in industrial applications, such as in an asphalt seal tank. The agitator with a shaft going down the center of a round tank uses a graphite rope seals on the shafts to seal the tank when it's over half full. I've had to replace these before, and the graphite will hold for a few years in this application. That said they have more pressure on them when the tank is full of sealer than an engine does when running. They also have a 20 foot shaft that is flexing under load while agitating the tank, it's a wonder they seal at all.... LOL.

The older water faucets stems also used graphite rope seals and usually have to hold roughly 60 PSI of water pressure and hold up pretty well there too.

[GTOGEORGE]

Originally Posted by Dragncar

So the one piece, you "stretch" it over the flywheel flange ? The Caddy seal I have has a large wire in the middle of it, not happening if one piece.
Asking because at this point I have never actually laid my eyes on a BOP or any modern Pontiac rear main seal.
I know it was such a issue in the 80s the SS guys would reuse their old asbestos seals because of availability and the drag a new one on the crank.

No the BOP one piece seal........you make a cut/ slice with a razor blade, slip it on the crank and set the crank in. Pretty simple not even you could mess it up......but a rope seal would be cheaper! LOL!
Heck I have an used one (3” main) I’ll sell you for 5 bucks!
GTO George

[JSPONT]

I re used my 1 piece on my build, bone dry still!!

[GTOGEORGE]

Originally Posted by JSPONT

I re used my 1 piece on my build, bone dry still!!

Yea I was going to reuse mine but there not that expensive so what the heck!


GTO George