Permatex Aviation Gasket Former.-

[Sea Rider]

Plan adding a light coat of such product at each side of the crankcase and cylinder head mating surfaces to paste up the edge's contour porosities the motor has developed over the years running in salt water. . The manufacturer recommends once a thin coat is applied at each surface let it air dry a few minutes. Question : how many will be enough, must the surface feel tacky to the finger prior sandwiching the new gasket in ?

Happy Boating​

 

[Chris1956]

Johnson/Evinrude have their own recommendations as to what to use on crankcase edges. It varies by year.

On my '98 V6 they specify OMC Locquic primer followed by OMC Gel-Seal II

Om my 1959 Fat Fifty, OMC specified permetex #1 hard setting gasket compound.

What does your engine specify?

 

[racerone]

I think Searider just calls the engine block the " crankcase " here.-----Talking about putting cylinder head onto the engine..-----I believe " Island speak " is not always the same as the way everybody speaks.

 

[Chris1956]

OK, on my '98 cylinder heads there are water passages and Orings. Silicone caulk around the water passages, Grease on O rings.

 

[Faztbullet]

If the gasket is silicon impregnated you cannot use a sealer...

 

[Texasmark]

For metal to metal head gaskets I always use Copper Coat product, in aerosol or brush/can......made especially for the purpose. Agree aluminum framed Silicon gaskets get no sealer in casting matings., one application comes to mind, Feldpro intake manifold to engine block/head interface gaskets on GM late '90s vehicles. I use the product you mention to seal sheet metal covers to castings like automotive transmission sump covers, cork gasket and glue on casting side only. Haven't tried it bare, like the silicon gasket maker products that use no gasket with their sealer.

 

[Sea Rider]

The block's and cylinder head edges are not mint so will brush a light coat of Permatex Aviation to both mating surfaces and install the 2 sided pre glued coated gasket in between as there's no silicon impregnated whatsoever. For exhaust cover gaskets need to brush sealer at both sides, PA has worked fine in previous restorations. After both gaskets sits dry and well torqued to specs will brush some enamel/varnish coats in the cylinder head and exhaust covers contours to avoid salty white lines formation.

Happy Boating​

 

[Sea Rider]

It was a real bad idea to have added a light coat of Permatex Sealer at both gasket's sides when installing a brand new OEM head gasket, while torquing the head to specs another block's thread went kaputt . ​

When the head was removed to repair the stripped thread the new head gasket was found in a non reusable state. PS bonded so strong to both mating edges that peeled off the original coating to expose the internal dotted alum sheet. Lesson learned don't coat any gasket which already has been factory delivered pre coated with anything else. If another thread is pulled in the torquing process will be safe to have it removed as a whole, happens that the pre glued gasket only bonds to both internal matting edges when the motor is finally turned on and run for some minutes upon restoration.

When restoring an old long hour run motor in salt water expect to break some bolt's heads, strip internal block's threads due to oxidation, corrosion and metal fatigue scenarios in which will need to learn to deal with.​

Happy Boating

 

[Chris1956]

I doubt the Permatex caused the thread strippage. It did cause the rest of the mess, however.

 

[Sea Rider]

I doubt the Permatex caused the thread strippage. It did cause the rest of the mess, however.

Permatex has nothing to do about stripping the block's thread, just screwed the new head gasket nicely beyond possible reuse....

Happy Boating​

 

[Bondo]

Permatex has nothing to do about stripping the block's thread, just screwed the new head gasket nicely beyond possible reuse....

Happy Boating​

Ayuh,...... Did you use #1, or #3,..??
#1 hardens,....
#2 is a putty,.....
#3 doesn't harden, but stays tacky,.....