Perfect Seal on head bolt threads?

[Rick Stephens]

The Merc manuals all (I have a morphodite bastard 4.3L and have several manuals open while I work on it) state to coat head bolts with Perfect Seal - easy enough to get a different brand replacement of Merc's camel snot sealer now that they no longer make it. I have never ever done that to a head bolt on any other engine ever in my overly long life. Is that really advised? (I know, probably everybody who has mechanical capability already knows the answer and I'm just a rube)

Thanks!

Rick

 

[Scott Danforth]

head bolts on the 4.3, 5.0 and 5.7 go into the steam jacket. so yes, need to put sealant on threads. most new head bolts come with sealant pre-applied.

I have used loc-tite thread sealer myself, however I have also used permatex #3

 

[Rick Stephens]

head bolts on the 4.3, 5.0 and 5.7 go into the steam jacket. so yes, need to put sealant on threads. most new head bolts come with sealant pre-applied.

I have used loc-tite thread sealer myself, however I have also used permatex #3

Thank you for the answer. I have a can of the Loc-tite thread sealer here. The bolts on the motor were new with the factory sealer, but torn up after use. Had to rebore the motor since the PO let it fill up with rain water.

 

[Fishermark]

I too use the Permatex sealer - I thought it was #2 however. Whichever one is the non-hardening sealer.

 

[Rick Stephens]

This is what I own and have used for a non-hardening sealer. I have seen it listed as an alternative to Perfect Seal. Should be called Camel Snot.

 

[Bondo]

I thought it was #2 however.

Ayuh,.... Form-a-gasket #1 is the liquid that hardens,.... aka; like the ole Indian Head shellac compound stuff,...
#2 is the non-hardenin' Paste,....
#3 is the non-hardenin' liquid, that I use in place of Perfect Seal,... per Don S,....

The stuff you've got Rick, is just Fine, same stuff, different brand,....

With the head bolts goin' into the water jacket, ya gotta atleast use a sealer, pipe dope can work in a pinch,.....

 

[Rick Stephens]

I feel kind of dufus at the moment. Been since the '80's the last time I built a small block chevy. Even the Felpro gasket instructions state clearly - use sealant or you won't get even torque.

Thanks for the feedback. Old brain and dead cells.

Rick

 

[Fun Times]

Perfect Seal - easy enough to get a different brand replacement of Merc's camel snot sealer now that they no longer make it.

Just for confirmation Rick, Have you heard something different that they (Mercruiser) stopped producing/selling Perfect Seal?

Just for an confirmation I just checked with a good friend that owns a high volume Merc parts dealer and he mentioned they still sell it.:noidea:

 

[Rick Stephens]

Just for confirmation Rick, Have you heard something different that they (Mercruiser) stopped producing/selling Perfect Seal?

Just for an confirmation I just checked with a good friend that owns a high volume Merc parts dealer and he mentioned they still sell it.:noidea:

Nope. I had gone looking and couldn't find any. Also came across posts stating it was no longer made. I see a couple places have now, though. Lots more expensive over the lok- tite stuff.

 

[Rick Stephens]

Getting cold out here - teens. Got it to long block though. Thanks for the help.

 

[Grub54891]

Just bought some perfect seal about 6 months ago, must have quit making it since then??

 

[Rick Stephens]

Just bought some perfect seal about 6 months ago, must have quit making it since then??

No - I went looking for it last spring by part number and couldn't find squat. I see even Michigan Mtrz has it, now. My error. I swear I couldn't find any.

 

[bruceb58]

Off topic...what are you doing to the engine?

 

[Rick Stephens]

Off topic...what are you doing to the engine?

I bought a donor boat with it in it. Donor boat had a newly rebuilt 4.3L V6 in it and Gen2 outdrive that I coveted enough to bring home. I got the motor running and it first blew out rust on the right side and the compression was all over the place. So I took it apart and found that PO had let water get into the motor and cylinder 6 was rust pitted badly. Everything else is literally like new inside. So we punched the cylinders out and replaced pistons and rings and I am reassembling.

This motor and outdrive is going into my old 17 footer. Pretty much have the mounts glassed in, replaced about 1/2 the transom while I was at it. Paint, carpet, a bunch of electrical to build and I'll be adding a 100HP to my fishin rig.

​

 

[denisg1]

The headbolts can rust severely on their shanks, but not on the threads . I credit perfect seal for protecting the threads. Perfect seal is no longer made.
it is suggested to coat the threads wit permatex. .Permatex is not perfect seal but it might do the same thing. It must do two things: 1 protect the threads and 2 give an equivalent torque reading. There is a locktite for retaining studs, it may be ok. I usually paint Mercruiser bolt shanks as corossion is common on them. i suggest sealant under the headbolt flanges as that will help exclude water entry there. At least permatex is available widely but As to the torque when using it, I have no clue.