need advice on gasket selection

[jsmith]

My 87 T is leaking like a siv, Its time to replace the oil pan gasket, rear main seal, and valve cover gaskets. What is the best brand or type to use? What does everyone recommend? Are cork the best or something else? and do you guys put anything on your gaskets(especially the cork type) during assembly to help them seal? I only want to do this job once so any advice would be greatly appreciated. Also I am going to replace the motor and tranny mounts while I am at it (135,000 miles on original mounts), are stock mounts ok or should I spring for something better? It is basically a stock motor with the usual fuel system upgrades, big mouth cold air kit, 3 inch downpipe and exhaust. stock turbo still(probably changed at some point) and many other small upgrades, nothing too exotic. My goals are good reliability and able to run low 12's. So what mounts do you all recommend? Are stock mounts good or do I need to spring for the poly mounts?

Thanks for the advice. Jeff

 

[turbofabricator]

The cork oil pan gasket from any of the listed vendors works the best. Clean the pan and block with brake clean and then smear a light layer of Ultra-Black silicone on both sides of the gasket, then install. The rear main seal needs to be replaced with a neoprene one and discard the rubber side seals in the kit. After you carefully clean the sides of the block and the main cap, install the seal halves in the block and the main cap. You will have to lightly lube the seal first and wind it over the main journal and then leave a 3/16" section sticking out of the block on one side. Then install the seal in the lower main cap and leave a 3/16" section sticking up on the opposite side of the one you left on te block side. In other words, stagger the interface seam on the seal halves so they do not line up with the parting line of the cap and block. Then apply a light film of Ultra-Black on the rear edges of the cap surface from the seal outward, then lube the bearing with Hyper-lube or STP and then lube the main bolts with 20w-50 oil and then install and torque the main cap to 100ft. lbs. Then take a good caulking gun with a tube of Ultra-Black in it and pump the two side cavities full of silicone and watch to see that it squeezes out of the front and back of the block. This will make a leak-proof seal. Then install the oil pan and gasket.
The valve cover gaskets are fine with cork, but most aftermarket valve cover gaskets need a little trimming to get them to fit in the channel correctly. Some guys like the rubber ones, but either way they need attention after few years, anyway. If a Buick doesn't leak a little oil.........better add some. That's why the Land Rover guys bought the Buick engines....they already leaked oil and they didn't have to find a way to make them leak. That's why the Brits never made a TV set........they couldn't figure out how to make them leak oil!:biggrin:

 

[jsmith]

Thanks ken, that is alot of useful info, I really appreciate your time. One more question, whats your thoughts on replacing the motor mounts. Stock or aftermarket?

Thanks again, Jeff

 

[johnnyttype]

If a Buick doesn't leak a little oil.........better add some. That's why the Land Rover guys bought the Buick engines....they already leaked oil and they didn't have to find a way to make them leak. That's why the Brits never made a TV set........they couldn't figure out how to make them leak oil!:biggrin:

lol... my friend owns a Land Rover with a 96 4.0 liter V8 and it definitely leaks like a buick!!:biggrin:

 

[lhbarrett]

New Gaskets

Wow sounds like are cars are related (136K). I just finished (almost) the same service. You might consider the timing chain, water pump, thermostat, intake gaskets, PCV valve, injectors, & oil pump inspection. I used all GM gaskets bought from Johns Performance (very helpful tech info) except for the intake and valve covers. While it was apart I had the intake powder coated along with misc brackets. I used motor mounts from NAPA along with most other parts that the T needed. I followed the instructions from the board here on the how to articles and took lots of digital photos as I constantly forgot how it went together or broke the plastic vacuum lines. I also inspected all the vacuum check valves and found them cracked or not working. Now if I had not punctured the radiator during all this I would be back on the road.

I thought I saw some poly mounts in the For Sale section this weekend.

Regards,
Lance

 

[boostingbuick]

I am an old land rover tech and I have done thousands of rear main seal/cross seals on those. And for those who don't know, its a buick engine in those solid axle trucks. They do have the leaking rears in common.