Cam Seal Leak - What Sealant?

[mca]

I developed leaks at both cam seals. I used Curil-T on the o-rings and paper gaskets 4 years ago during the rebuild.

Instead of using the normal red o-rings I bought green Viton o-rings hoping that they would prevent future leaks.

Is there a better sealant to use or should I stick with Curil-T?

[john walker's workshop]

silicone paste on the o-ring and make sure it doesn't get caught and pinched as you tighten the bolts. i use a very thin coating of dirko on the paper gasket. a dab between thumb and forefinger and work it around the gasket. years ago, i found that K&W spray coppercoat penetrates and softens the gasket and they split when the bolts are toightened. not so with the dirko. and resurface the plate with some 80 grit on a flat surface.

[mca]

Wonderful.

Is there a particular brand of silicone paste that I should use?

[KTL]

Dow Corning 111 or 112 is good stuff but expensive. Plus the tube is so big (think, large tube of toothpaste) you'll never use it all in your entire lifetimes. Sil-Glyde or Permatex disc brake caliper lubricant will work too. Both are silicone lubricants and you can find them at your local auto parts store like Autozone, PepBoyZ, etc.

[JFairman]

Silicone grease on the oring is probably best there and will lube it while sliding the cam thrust plate into place in the chain case.
I didn't have any when doing that and used non drying greasy permatex blue hylomar sealent that I can't find anymore on the red oring and paper gasket.

5 years later there is still no oil sweat or leakage around that connection. I also spread a thin layer of hylomar on the paper chain case cover gaskets and they are still dry too. Hylomar never dries and wipes off with laquer thinner on a rag real easily anytime later.
Someone had used used loctite 574 or something similar on those paper gaskets in the past before I got the car and it's a real pain to clean off. You have to remove all the studs in the chain case just to carefully scrape it all off. I hate that stuff and there's no reason to use it there.

Unfortunately the only blue hylomar I've found locally recently was at harbor freight tools of all places 2-3 years ago. It's made in the UK and a little different consistancy and seems to get really tacky and sticky faster as the solvent evaporates than the old permatex stuff I used to find in tubes at local auto part stores.

Wurth probably still sells tubes of the good stuff I remember. I've heard it was origonally made for the old Rolls Royce Merlin V12 aircraft engines.

[KTL]

Originally Posted by JFairman

Someone had used used loctite 574 or something similar on those paper gaskets in the past before I got the car and it's a real pain to clean off. You have to remove all the studs in the chain case just to carefully scrape it all off. I hate that stuff and there's no reason to use it there.

Amen brother! My recent build had 574 slathered in all sorts of undesired places.

The only places I use 574 are the case main webs and on the cam towers. I try to use as little of it as possible.

[mca]

What about installing the paper gasket dry?

I installed chain housing / chain cover gaskets dry and they are still free of leaks. Just wondering if that is a viable option for the cam gasket.

[mca]

How about this stuff? In the commercial they apply a torch to it. Seems like it could tolerate engine heat.

[KTL]

I'm so sick of that fat guy in the commercial riding around in the rowboat with the screen door covered in flex seal......

Keep in mind that this cam leak location is under pressure. It's not a dribbly leak from splash oiling. The cam bearing is getting pressurized oil right behind that paper gasket. So i'd want to make sure your fix is a tight seal just like a new gasket. Blobbing some goop at the leak point is probably not going to work.....

[mca]

Ya I'm just joking. Would be fun to try that stuff on something.

[KTL]

Nah I know you're kidding. Just had to throw that response out there for someone who may search in the future for how to fix this leak. It's a pesky one and there's really no good way to do it w/out removing the chain housing.

[mca]

Think u mean chain covers .

I'm waiting on new chain sprockets. Should have it all put back together this weekend.

Of course I can never drop the engine without doing a bunch of other clean up. Decided to replace the rubber in the engine bay since mine is all wavy (lets too much dirt in). Then I cleaned up the tranny, CIS, replaced some vacuum lines, heater hoses, etc. It is too freaking hot right now to drive the car anyhow!