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MG TD TF 1500 - Gasket Quality

Last week I was assembling my XPAG engine for my TD. I used Permatex Red on both the block and the sump. Since I was dumb enough not to put the flywheel on first I had to take it apart today. When I took it apart the gasket split in two. Half on the sump and half on the block.
As you see in the photos the gasket shows evidence of oil penetration.

Is this normal?

It only appears on one side of the engine. I never added oil to the engine but there is a small amount of oil lining the inside of the block. I probably rotated the engine on the engine stand such that oil would flow on that side of the engine.

It seems to me that with the engine full of oil and operating at high temperature the oil would seep all the way through the gasket and leak.

What am I missing here?

TIA,
Mort

M Resnicoff

Sump Side

M Resnicoff

I don't know about the soaked cardboard, but you are so lucky you had to pull it apart. Your excessive use of Permatex had almost completely occluded the oil passageway in the pan. You would have had no oil pressure. Presuming I'm looking at the picture correctly, near miss. Sometimes things happen for a reason. George
George Butz

Thank you George.
I noticed that when I took it apart. Sometimes it pays to be ignorant.
The next application will be much more judicious.
Mort
M Resnicoff

Mort

I think I would be copying the method the old timers used. Many a gasket has been cut from cardboard boxes and coated with "Rolls Royce Gasket Cement" prior to assembly to prevent oil penetration.

The issue with Permatex is that it only sits on the surface.

Graeme
G Evans

The stuff that was recommended to me in the 60's was aviation grade Loctite gasket cement. There are two types. I use the one that never goes hard. I hadn't used it for about 40 years but it's nice to know it still smells the same. I also make my own gaskets from some really high quality gasket sheet that I picked up all those years ago. Cheers
Peter TD 5801
P Hehir

A dab of Permatex RTV fine for the rear corner area where the cardboard meets the cork/ block junction and around the front timing cover area. Keep it far away from any oilway. I second Peter on the av sealer. I have used Permatex Aviation Form-a-Gasket for years. It comes in a small bottle with a brush in the screw on top. Messy, but cleans up with rubbing alcohol. Great for carb and other gaskets too.
George Butz

George, Peter,
With the aviation gasket maker do you use a gasket or just the compound?
M Resnicoff

Mort, I've never used the Permatex Aviation Form-a-Gasket product as a gasket, only as an adhesive for gaskets. Bud
Bud Krueger

It is really thin and runny, so you have to use a gasket. As Bud says, you can use as an adhesive to hold a gasket in place.
George Butz

Mort, I know several guys that use 3M trim adhesive on one side and nothing on the other. I have used it with good results and also have had good luck with Hylomar. A little story concerning Permatex Silicone. I had an old Jeep I bought that the oil pressure gauge was always bouncing from zero to normal; I thought it was a bad gauge. One day on the interstate it went to zero and stayed. I kept going and it wasn't long before a trail of smoke was behind me and the engine was banging. Once I slowed down the engine threw a couple rods. When I tore the engine apart the oil pump had bits of silicone blocking the passages where a PO had used an excessive amount of Permatex Blue for or on the gaskets. The oil pickup screen was also clogged with silicone.
rich40701

Years ago a long defunct shop near Orlando rebuilt a local guy's TD engine. No oil pressure. Same problem, blob of RTV in pan pick up hole. Seems to be a common problem. George
George Butz

Mort I always use both a quality gasket material & the aviation grade Locktite on both sides of the gasket. Too many horror stories like Rich's with silicone & the other heavy goops. Cheers
Peter TD 5801
P Hehir

Just a couple of follow-up notes:

On another thread D. Peltier suggested the use of Permatex 85420. I have ordered some of the material and thanks to Amazon it will be here tomorrow. It looks like a good solution for my engine. Does anyone else have experience with this product?

I prepped a new set of gaskets with a fan coat of silicone on the inner edge to prevent oil penetration.

Mort

M Resnicoff

My sealant of choice is Yamabond (obviously available from Yamaha dealers) or Tri-bond (the same stuff but without the Yamaha name). It is grey and does exactly what I want it to.

Tom Lange
MGT Repair
t lange

I see us getting into an issue of cements for gaskets and cements in lieu of gaskets. I'm going to open a new thread called 'Necessity for sump gasket. Bud
Bud Krueger

This thread was discussed between 10/02/2017 and 14/02/2017

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