Going through and doing all the gaskets and seal and have read alot of posts different place on guys saying they use the 460 rear main seal in the 455, I was just curious if anyone that has done it has any feed back on it, how long it's been in? Any leaks? Guess I'd like to know if it holds up? I'd hate to put it in and have a leak and have to pull it back apart

 

My short block has been running one for the last 12 years, my dads truck longer than that. If its installed right, they dont leak.

 

Any tips on the install? Do you know the felpro part# of the 460 seal?

 

Near the bottom:

Valve Cover Gaskets -- VS13403R -- 3/32" thick rubber
Valve Cover Gaskets -- VS50359R -- 11/64" thick rubber

Oil Pan Gasket Set -- OS30471C -- Diesel Engine Type, Metal Impregnated Rubber

Oil Filter Base Gasket -- 9948

Intake Manifold Gasket Set -- MS96009 -- Turkey Tray, Small Block
Intake Manifold Gasket Set -- MS96004 -- Turkey Tray, Big Block
Intake Manifold Gasket Set -- MS96027 -- Turkey Tray, Universal
NOTE: Turkey Tray Gaskets protect the HOT bottom of the manifold from splashed oil, the other kind don't.

Conversion Set -- CS81712 -- Timing Set + Oil Pan Set + Oil Filter Pedestal

Distributor O-ring -- 424

Exhaust Gaskets -- MS90021 -- Standard Type
Exhaust Gaskets -- 1439 -- "Racing" Type, 3 Times More Expensive, not sure why
NOTE: exhaust gaskets are not absolutely necessary if manifolds are straight

Timing Gasket Set -- TCS 13417 -- Gaskets and Oil Pan Seal - No Sleeve
Timing Gasket Set -- TCS45270 -- Includes Speedy-Sleeve for Repairing Balancer Groove

Rear Main Seal -- BS6141 -- Small Block Neoprene Ford Type (Y-Block 239, 256, 272, 292)
Rear Main Seal -- BS13879 -- Small Block Neoprene AMC / Jeep Type (196, 199, 232, 258)
Rear Main Seal -- QBS40032 -- Big Block Neoprene Ford Type (460)

PCV Valve Grommet (Valve Cover) -- 42314 -- Dorman HELP! Number

 

Install with the lip toward the inside of the engine and all will be fine.

 

Following. A little rub with emory cloth and a light smear of silicone for lube?
Good morning Ed, Hope your feeling better.

 

Suggest you look at the BTR Olds engine videos on V8 TV for the S71 Olds build.

He has a specific way of installing these seals.

 

I put it in last night, piece of cake, just waiting on oil pump,water pump and fuel pump and it can all go together

 

Did you perform the BTR modification first?

 

All I did was loosen main caps 1-4 and removed #5, lifted the crank, got the rope seal out with a pick, used a scotch brute pad on crank, put seal in block and cap, coating of grease on them, dab of ultra black where they meet and put it back together

 

So I guess that means "No".


Why ask for help when you ignore the advice given?


Bill Trovato (BTR) is the leading Olds engine builder anywhere.


His advice is top notch, and is what I follow.


Hopefully you won't have to redo the seal again.

 

I did the seal before you posted about the bye mod. Had I know maybe I would have looked into it

 

Any idea which volume has this information? Thinking of rebuilding my rocket 455 next year and want to save and tag important details. Thanks!

EDIT: Found it in Video 3. Thank you again for the reference!

 

The Ford seal is .002” thicker on the outer surface because the OD of the block cavity is .004” larger dia

Wanna bet there’s more variation than that from seal to seal?

the shaft dia difference is .006” bigger for the olds. So .003” per side

theoretically that’ll give .005” more crush per side installed as is.

 

The best Ford seal to use are the blue high performance ones. They are softer and more forgiving

or you could opt for the expensive 1 piece Ford rear seal at 5 times the price. Super slick material

 

I've always used the black Felpro seal. Do you have a part number for the blue seal?

 

I have never had a problem with the Ford seal in an Olds. I just install it with the parting surface slightly offset from the main cap parting surface. The one in my "E" block currently has been in there since 1988.

 

FelPro #2948 it’s Viton. Last one I got was grey

 

Thanks. I will give it a try.

 

I've only done that to one engine. Guess what's coming back for a rear seal replacement here soon? Coincidence? Maybe, but I've never had an issue not doing it.

 

I've been using the Ford seals (460 in the BBO and Y-block in the SBO) since the 1980s with zero issues.

 

Description on websites for the #2948 high perf seal says it’s Viton. I just looked at one I have here,, it says premium fluoroelastomer. It’s dark grey

 

I'm not familiar with 2948, but BS40654 is Viton.

 

The #2948 is a premium race seal that was designed for use with a crankcase vacuum pump. No problem using it in any application

 

To change the rear main seal, if i have never replaced my main bearings, is there a worry about loosening the caps and having them not seat properly upon reinstallation and re-torquing.

Also, is there anything worth inspecting since i will be changing the seal. I have read about people using a plastigauge to check bearing clearances. Is it worth doing with old bearing to see what kind of shape they are in?

Cheers
Tony

 

It wouldn’t hurt to pull a couple bearing caps just to see how things look. At the same time, if you don’t like what you see it will always be in the back of your mind.

Clean out the oil pump pickup, hopefully it’s not full of nylon.

If the timing chain hasn’t been changed, this is the perfect opportunity. Installing the timing cover with the pan on is a pain, since the pan is off that makes it much easier.