39 Head torque

[SuperDave]

Edmund (sp?) finned aluminum, 40? 45 ? "Best" brand gasket. Copper coat ?

[flatjack9]

45 lb, Best gaskets are fine. No copper coat.

[Ol' Ron]

Yes, #45 is more than enough. However, you should do this through at least 3 heat cycles. THis will insure compressing the gasket. Now if these are new heads they should be checked for piston clearance. Looking foe .045/050" for best preformance and economy.

[WestCoast]

motors manual says 35 to 40# for aluminum, I don't like copper gaskets with aluminum heads, worry about electrolisis, it my never happen but I play it safe

[SuperDave]

I just noticed that there are two different head gaskets for this engine. one type has round water passage holes in the center, the other has trapezoidal holes.. Does it make a difference?

[Kube]

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Originally Posted by SuperDave

I just noticed that there are two different head gaskets for this engine. one type has round water passage holes in the center, the other has trapezoidal holes.. Does it make a difference?

I'd suggest you match the gasket to the engine (hole). The trapezoid hole is Ford, the round hole is Merc.

[JSeery]

Kube ? I wasn't aware of a Ford vs Mercury block, an additional detail?

[Kube]

Originally Posted by JSeery

Kube ? I wasn't aware of a Ford vs Mercury block, an additional detail?

At least in '39 - '40, the center water passage was different between the Ford and Mercury castings. Ford had a trapezoid shaped passage while Mercury had a round passage.

[JSeery]

Originally Posted by Kube

At least in '39 - '40, the center water passage was different between the Ford and Mercury castings. Ford had a trapezoid shaped passage while Mercury had a round passage.

Thanks, didn't know that! But then there's lots I don't know!!!

[john in illinois]

This is from Best for copper or graphtite gaskets.

Install using using a spray-on sealant like K & W Copper Coat or Permatex Copper Spray-A-Gasket. Always re-torque, no short-cuts.

John

[flatjack9]

What holes are in the head? I have always used the gasket with round holes. I believe Ford went to these as a service gasket.

[SuperDave]

The head is in the machine shop, so I can't match it up to the gasket yet. The gasket that matches the block has the trapezoidal water holes in the center and has larger water holes in the lower section. I'll take some pictures when I have all the parts here.

[rotorwrench]

A friend of mine always put a good coat of silver aluminum pigment spray paint on copper gaskets instead of copper coat. His explanation way back then was that it wouldn't corrode as easy. Knowing what I know now about dissimilar metal corrosion, it makes even more sense to me now. The aluminum pigment paint would block the copper from the aluminum head better as well as provide a bit of sealing.

Best gaskets are pretty good stuff but sometimes you have to play with the gasket thickness and copper is the only way to really do that. It just depends on how you build the engine.

Ford played around a fair bit with the deck ports. 221 24-stud would have trapezoidal center ports. 239 engines were round in the center. A lot of gaskets choke down on some of the ports to slow the flow in certain areas. They just have small holes in the gasket while the deck ports will be larger.

[SuperDave]

If I did it right, there should be two head gaskets pictured.

[SuperDave]

It worked ! The top one is the one I removed. The bottom one is the new one I am going to install. The top one not only restricts water flow in the center, but also has smaller water holes on the bottom between 1&2 and 3&4. This is a much better match to the block. Machine shop is dragging it's feet.

[rotorwrench]

Ford actually restricted some of the ports for a reason. This way they could control the flow around the cylinders and especially through the head a bit better to relieve hot spots. The 8BA blocks had larger ports at the back of the decks to flow more from rear to front but it made the decks a bit weaker. I don't get real worried about the gaskets changing the coolant flow.

[flatjack9]

The upper gasket directs more flow to rear cylinders and is a much better gasket than the lower one. The upper still allows plenty of flow at the middle.

[SuperDave]

Bad news... Got the head back from the 'shene shop.. They cut it .012. I didn't like what I saw. The head was bowed with the center raised. Making the end chambers slightly smaller.Couldn't find my magnetic mount for my dial indicator. (probably loaned out!).I should have stopped but being an optimist... I put the head on without a head gasket. Cranked engine over by hand and nothing touched (that I could feel). Checked the thickness of the gasket I took off, "Best". Found the compressed gasket measured .058". I figured there should be enough clearance if the new "Best" gasket compresses the same. I would bet that the deck was cut at some time since it is a .040 over bore. It certainly had a major rebuild along the way.. Every thing was great up to the third torqueing after two runs and cooling. Third torqueing went OK but when I started it up.. knocking! Removed the head and found the front and back exhaust valve just barely touching the head. So Now it looks like we are looking for new heads. If it was my car I would opt for stock iron and dress it up with chrome nut covers but the owner likes the Bling of the finned heads. I keep telling myself that this is a fun hobby.. It sure as heck isn't a profitable one! Anyone have a set of uncut finned heads?

[flatjack9]

Originally Posted by SuperDave

Bad news... Got the head back from the 'shene shop.. They cut it .012. I didn't like what I saw. The head was bowed with the center raised. Making the end chambers slightly smaller.Couldn't find my magnetic mount for my dial indicator. (probably loaned out!).I should have stopped but being an optimist... I put the head on without a head gasket. Cranked engine over by hand and nothing touched (that I could feel). Checked the thickness of the gasket I took off, "Best". Found the compressed gasket measured .058". I figured there should be enough clearance if the new "Best" gasket compresses the same. I would bet that the deck was cut at some time since it is a .040 over bore. It certainly had a major rebuild along the way.. Every thing was great up to the third torqueing after two runs and cooling. Third torqueing went OK but when I started it up.. knocking! Removed the head and found the front and back exhaust valve just barely touching the head. So Now it looks like we are looking for new heads. If it was my car I would opt for stock iron and dress it up with chrome nut covers but the owner likes the Bling of the finned heads. I keep telling myself that this is a fun hobby.. It sure as heck isn't a profitable one! Anyone have a set of uncut finned heads?

Obviously they had to be touching when you tried it without a gasket! A little grinding and you will be just fine. I would use the aluminum foils balls to check clearance before you finish the job. An ounce of prevention is worth a pound of cure.

[JSeery]

Why not just clearance for the valves? Not that difficult.