Head gasket sealer

[GARY F]

37 Olds , L37 flathead. 8.  Should I use a sealer on the head gasket and if yes what brand should I buy?   Also how about the intake/exhaust manifolds. Thanks Gary

[Spinneyhill]

New gasket? head and deck perfectly flat? Just the gasket. That is all they used in the factory.

[FLYER15015]

X 2 to what Spinny said, and you know to tighten BOTH from the center out in a spiral pattern IN SEVERAL STEPS till the correct torque is achieved.

 

Mike in Colorado

[jan arnett (2)]

Then retorque after about 50 miles.

[Spinneyhill]

....When cold. 60-70 lb.ft.

 

Edited October 8, 2019 by Spinneyhill (see edit history)

[edinmass]

I use Napa copper head gasket spray.............stops the gasket from sticking and sometimes you can reuse the gasket. On a perfectly new surface, head and deck, dry is ok with factory type NOS gaskets, today, the materials are different.......and failure is more common. Having done hundreds of head gaskets..........I would use the Napa Copper Gasket Dressing.

 

Its Permatex Brand, I buy it at Napa. 

Edited October 8, 2019 by edinmass (see edit history)

[cahartley]

Hylomar Blue has never failed me.

 

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&ved=2ahUKEwje5-7sgIzlAhVJKa0KHYC_ApAQFjAJegQIARAC&url=http%3A%2F%2Fhylomar.com%2Fwarrick%2Fwp-content%2Fuploads%2F2013%2F10%2FHylomar-Universal-Blue-Issue-8.pdf&usg=AOvVaw3ovgirdmDM5sfzrlcaFAKj

[Grimy]

I agree with Ed and his recommendation of aerosol copper.  I want to point out that in my experience a vintage copper-asbestos-copper gasket usually needs only one re-torque (do it cold on prewar cars), but the reproduction sandwich gaskets with some form of plastic rather than asbestos require multiple re-torques, perhaps as many as five, before that material finally takes its permanent "set."  And likewise on your manifold gasket for an inline 8, although I just "snug" manifold fasteners on inline 8s because they must move a bit to keep from breaking.

[trini]

I remember solid copper gaskets  in 4 cylinders British engines. It can be reused by cleaning and heating over a coal fire. The copper swells . but I do not think that will work on a straight 8. If the head and the block is true an asbestos /copper gasket needs no sealer. What you have to watch out for is some of the head bolts or studs might be touching the water in the water jacket and seeps through the threads. Use some kind of sealer on those threads.  

[GARY F]

I want to thank you all for your replies. A little more detail of what I am doing. The car has not run since 1975. Besides correctimg things the other owner butchered up I did a lot of cleaning and tried a compression test and got a lot of zeros.   So I pulled the head to see the valves which were open. Pulled the side covers and freed up the lifters and checked there setting and cleaned the area.  Motor turned free when I first got it. No ridge on cylinders.  I have a shop manual and it says about putting some kind of 1937  sealer on, that is why I asked the question. I got my gaskets from Olsons.  Motor turned nice with battery when doing the comp. test. I also bought all new head bolts  Again  Thanks

Edited October 8, 2019 by GARY F (see edit history)

[Graham Man]

2X on the copper coat.  I also use anti seize on the head studs, just the sides where the head contacts the studs.  I use water till I am sure there are no leaks, then put in antifreeze.

 

[19tom40]

If your gasket is made by Olson or Best Gasket company, they both recommend a copper spray. If it is a NORS Victor or Fel-Pro, the recommendation from the manufacturer is no sealant.

 

I would follow the manufacturer's recommendation, they engineered the gasket and it will give the best performance using their recommendations.

[Grimy]

2 hours ago, 19tom40 said:

If your gasket is made by Olson or Best Gasket company, they both recommend a copper spray. If it is a NORS Victor or Fel-Pro, the recommendation from the manufacturer is no sealant.

 

I would follow the manufacturer's recommendation, they engineered the gasket and it will give the best performance using their recommendations.

With respect, Tom, I still use copper spray with NORS asbestos-center gaskets on the theory that OEM manufacturers' recommendations were for virtually new (by today's standards) heads and decks.  Fifty to ninety years later, there are likely imperfections in those heads and/or decks which can often addressed successfully by use of this additional sealant. YMMV....  🙂

[19tom40]

George, I don't mean to get into an argument, but the Fel-Pro and Victor gaskets already have a coating that will seal the imperfections. Adding another sealer will defeat the purpose of the coating.

 

Most head gasket failures are caused by incorrect procedures in preparation and installation.The block and the head should be surfaced when the head gasket is replaced. Most blocks and heads from the early years have enough meat to facilitate this. The copper spray does not give a thick enough coating to seal any large imperfections and small imperfections should be handled by a good gasket. The threads on the fasteners must be clean and lubricated according to the engine manufacturer's specifications. The torque wrench should be checked for accuracy and the fasteners tightened in stages.

 

I believe that asbestos gaskets were last made in the 1970's and I would not trust them on my cars.