engine rebuild - question about sealer

Hello,

I'm in the process of rebuilding the engine in my 1969 MGB. It's my first time rebuilding an engine of any kind.

I'm curious about gasket sealers. I was getting to install the big front plate onto the front of the engine block. I wasn't sure I should put gasket sealer on the plate side of the gasket only, or if I should but it on both sides. What's the usual practice on that? What about on other gaskets?

Also, what kind of sealer do other folks prefers? Should I go with the silicone sealer in a tube, or with the thin stuff that you brush on? I've got some of the thin red Permatex sealer in the white can that brushes on. I used that on the rear crankshaft cap, following someone's recommendation on another post.

Hair-splitting questions I guess, but I just want to be sure I get this right.

In other work I've done, I always put it only one side with oil pan gasket and valve cover gasket. I know you don't put sealer on the head gasket. I just don't know about other internal gaskets.

Thanks,
David

I like hylomar as a gasket sealer.

I use the red Permatex. So far so good. For the side covers I use Permatax black to glue the gaskets to the covers first, let it set. Then a smear of the red on the gasket surface and engine surface, let the red tack up and install with new bolt seals.

ANother vote for Hylomar!

Ask 10 mechanics that question, and you will get at least 5 different answers. Anything from no sealer to every different sealer known to man has been used with good success, and little success. The real key is to make sure the surfaces are good and clean (and flat) and not overdoing it with whatever sealer you choose to use (the excess just squeases out, and gets into the engine). personally I use Permatex ultra black, but that's just me.

David- there are a lot of posts on this. If you do a search you'll find a lot of advice.

I've heard many machanics do the "swear by" thing.
My swear by is I've always stayed clear of silicone sealers because any excess beeds can brake off and get into oil ports. I've alway used a aviation sealer, the brown brush on type, You don't need to use much of it and if it sits for a long time just use the brush to mix it back up. With this stuff I use a light coat on both mating surfaces and both sides of the gasket.

So read the swear by's and make you're own. Good luck with the rebuild.

FYI E-bay has some good rebuild vidieo and if nothing else get yourself an "Official MG Maintainence Manual". It has a read cover and can be found on E-Bay, Amazon...

If you've never micked cranks, cylander... you may want a machinist do that. There's a definiate art to it.

I use Permatex Ultimate Black, as a long time Spridget racer,. the hardest thing to keep from leaking is the axles on a Midget race car, alot of guys race them for 20+ years and never fiquire out to keep them from leaking, my secret is simple, a good clean surface and Ultimate Black, I always used it on my race engines as well, and now my street engine, it the gooiest, stickiest best sealer out there in my opinion.

Permatex Ultimate Black X"howerermanyatthispoint"

The front plate is fairly easy to seal - I use Permatex (I think #2 - the stuff that stays flexible).

Now - the cork strip that seals against the oil pan is another issue.

Any special advice about the cork strip? Do you use the same sealer on it?

You're talking about the paper thin gasket, right?

On THAT particular gasket, I like to use the Permatex "Super 300" OR the Permatex "Aviation, Form-a-gasket No.3" Both of these come in a can with a brush in the lid, so, you are able to apply a nice thin even uniform coating. Another one that works well for THIS particular gasket is the Permatex "High Tack" - This comes in a white can, and I think its red too.

IF THIS is what you have, then it will work very well for this application. The one I'm talking about is: 98D, Item #80063

One thing I would cite anytime you decide to use a silicon, RTV type sealants is that the surface has to be spotfree, oil liquid free, otherwise they don't stick very well. Use carb cleaner or acetone and let it dry before applying RTVs. Some of them like the Ultra Black, and Ultra Gray and Copper are resistant to these liquids, so they work much better than the plain old blue or clear RTVs

But, for this particular application I'd use what I suggested above.

But, these are like oils, EVERYONE has there favorite.

B

Lot of good advice here. Thanks to everyone who has posted. Your experience is worth a great deal.