Head gasket?

[30 Closed Cab PU]

Be sure that the head gasket drops on easily before spraying on the copper coat. No fun fumbling around trying to get a sticky gasket to slide down onto misaligned head studs.

While test fitting the gasket, additionally test fit the head before spraying the copper coat.

 

[Y-Blockhead]

I'm very careful to spray the copper coat from the inside out to keep the outer edge clean leaving a crisp white gasket edge. Does nothing for performance but looks nice. If you get too much copper coat on and it squeezes out leave it alone until it is dry and shave the globs off with a sharp knife or razor blade. Try it while it is wet and it will make a smeary mess all over things.

Just curious. When you spray copper cote on your gasket what do you do about the overhang of the gasket due to the 5.5 head being physically smaller than a stock head/head gasket? I suppose you could mask it off?

I use the Best Graphtite head gasket without sealant.

 

[BRENT in 10-uh-C]

A couple of things to point out here;

Copper 'Spray a Gasket' coatings are a "band-aid" for something else that is wrong. I cannot think of a legitimate reason for using it if the cylinder head and the engine block deck surface has been properly machined. Some say it an insurance policy! Again, it is not needed however if used and the head and or block move due to thermal expansion where the tackiness of the Copper coating has been disturbed, then is there really a future benefit at that point? Likely it will do more harm than good. That is why most knowledgeable/reputable rebuilders will say "No." to using it.



As for increasing the torque greater than 55 pound, (-or insert any number over 50 pounds) you really do not receive any more clamping force that is beneficial.

The arbitrary 55# torque number is what the advertised rating is for fastener torque of a ⁷⁄₁₆ Grade 5 stud. This provides about 60,000(±) pounds of yield. The issue is the deck surface of the engine block is only 0.4375" thick (-which matches the thread depth for the size of stud) HOWEVER, the cast iron block with ⁷⁄₁₆" stud only has a yield rating of 44k pounds before the threads will be compromised (pull). With a Grade 2 or Grade 3 stud, this will never be an issue however with a Grade 5 or 8 stud, -and with additional torque placed on the stud(s), the deck surface is typically distorted when the studs are torqued that much.

An engine machinist with a good quality surfacer often finds the perimeter of the stud's threaded hole will be "proud" as the threads have begun to pull. In this situation, the only correct repair is to install a thread insert in each of the damaged holes. The irony is that 50# vs. 55# total clamping load is less than 100# -or about 1¼%. Again, make the block & head surfaces flat, and you don't need the extra torque amount.

 

[Werner]

Guten Abend lieber Dave.

If you retighten the Z-head screws repeatedly, do you only use the same torque or do you loosen every single screw a little beforehand?

Your copper spray irritates me. We have copper spray as assembly grease (it doesn't dry) or copper lacquer (it doesn't slide).

 

[Werner]

... As for increasing the torque greater than 55 pound, (-or insert any number over 50 pounds) you really do not receive any more clamping force that is beneficial.

Guten Abend Brent,


I didn't understand everything correctly because of the foreign language. But if a newly ground C-head still seeps a little past the composite seal, then a stronger torque must cause a higher pressure = joint tightness?

 

[BRENT in 10-uh-C]

Guten Abend Brent,


I didn't understand everything correctly because of the foreign language. But if a newly ground C-head still seeps a little past the composite seal, then a stronger torque must cause a higher pressure = joint tightness?

Hey Werner, -the thing that you must realize is a Model-A head is very flimsy and will distort easily. When resurfacing the head, it is easy to distort the head just when anchoring it down however if it is within 0.001 or so, it will seal. The surface finish is what is critical.

As mentioned, the RA finish of the head must be quality. In other words, if you cannot see your reflection from the head and block's gasket surface, then the surface finish grade is too low. My Kwik Way surfacing machine will consistently produce a 70+ RA finish. If the surface finish is above a 65 and the surface is flat within 0.0005 of each other, then there won't be any seepage. Just because it is a "newly ground" does not ensure the RA finish is acceptable.

 

[Terry NJ]

Hallo Werner, Viele Grüße. Wir haben kein Umlaut on diese "Ami" Maschinen. Kein ess auch. Aber, what Brent was talking about , as I understand it, was that 55 Lbs torque (25 kilos, I believe) was all that you can use without distorting the head and/or the engine block. Using more torque will damage head or block. I always assumed I could use 60Lbs with the first and second torquing and go back to 55Lbs after as the gasket compresses.
Terry

 

[1crosscut]

Just curious. When you spray copper cote on your gasket what do you do about the overhang of the gasket due to the 5.5 head being physically smaller than a stock head/head gasket? I suppose you could mask it off?

Not that much of it that shows and it hasn't been an issue to me.

Guten Abend lieber Dave.

If you retighten the Z-head screws repeatedly, do you only use the same torque or do you loosen every single screw a little beforehand?

Your copper spray irritates me. We have copper spray as assembly grease (it doesn't dry) or copper lacquer (it doesn't slide).

I don't loosen them first. Others do.

Brent, perhaps I will install my next head without using the copper coat.

 

[Agent Orange]

I use no sealant either.

 

[alexiskai]

As mentioned, the RA finish of the head must be quality. In other words, if you cannot see your reflection from the head and block's gasket surface, then the surface finish grade is too low. My Kwik Way surfacing machine will consistently produce a 70+ RA finish. If the surface finish is above a 65 and the surface is flat within 0.0005 of each other, then there won't be any seepage.

Wait a second, doesn't the Ra number go down as the finish improves? You're saying the Ra should be below 65?

 

[Y-Blockhead]

Just curious. When you spray copper cote on your gasket what do you do about the overhang of the gasket due to the 5.5 head being physically smaller than a stock head/head gasket? I suppose you could mask it off?

Not that much of it that shows and it hasn't been an issue to me.

I thought maybe you would trim the gasket since you want to "keep the outer edge clean leaving a crisp white gasket edge" instead of leaving ⅛" of gasket hanging out with sticky Copper Cote on it. Guess not...

I think I will continue to not use Copper Cote.

 

[nkaminar]

Definitely use a head gasket.

I have had better luck with the premium head gasket than the copper head gasket with the copper spray adhesive, part number B-6051-M. I have the 5.5 to 1 high compression head. The head and block must be flat and absolutely clean. I use a wire brush wheel on a drill motor and acetone for the final clean.

Using grease on gaskets is an old racer's trick, although I have never heard of it used on a head gasket before. The engines in race cars are torn down after each race day and the grease makes it easy to remove the gaskets.

 

[Jack Shaft]

Sandpaper,wire brushes emery cloth or scotch brite all remove metal.The best method for cleaning without any chance of distortion is a roloc bristle disc use it with a die grinder..

 

[shew01]

Sandpaper,wire brushes emery cloth or scotch brite all remove metal.The best method for cleaning without any chance of distortion is a roloc bristle disc use it with a die grinder..

Oddly, Amazon mentions Scotchbrite in this product’s description.

https://www.amazon.com/dp/B01D92OAJ2/?tag=atomicindus08-20

Does it contain Scothbrite as its abrasive?


Sent from my iPhone using Tapatalk

 

[nkaminar]

A wire bush with brass wire may be an alternative.

 

[jm29henry]

Thanks so much I was wondering about the spaying and keeping the copper spray from getting on the white part of the gasket
Is 50 foot lb for a original stock head correct,I will be installing new head bolts and studs I purchased the better ones from Berts I hope those are the strong ones, also should I put a little anti seeze on the studs going into the block.
I have been working 10 hour days my work has a shut down so next Saturday I will put back together

 

[Jack Shaft]

I use a quality sealant on the studs like permatex ultra grey,screw them in hand tight.

 

[alexiskai]

Sandpaper,wire brushes emery cloth or scotch brite all remove metal.The best method for cleaning without any chance of distortion is a roloc bristle disc use it with a die grinder..

I just cleaned my block surface tonight and I mostly used a Roloc green disc and then a white disc, both on a 1/4" shank in a cordless drill. They worked well, but there were a couple spots I wasn't making progress on and I discovered that a 4" nylon-abrasive wheel really did the trick.

 

[1crosscut]

On studs I use Indian Head shellac.

I like to wait about 24 hours after setting them into place before putting on the gasket and head. This allows the shellac set up a fair amount but still allows the studs to be turned by hand with a little bit of effort. This then makes it possible to adjust the amount of the stud that protrudes above the nuts if they are too low but is still stiff enough to prevent them from turning when spinning on the nuts.

Lacquer thinner works well to remove any shellac that squeezes out of the threads after screwing them in.

 

[Jack Shaft]

I just cleaned my block surface tonight and I mostly used a Roloc green disc and then a white disc, both on a 1/4" shank in a cordless drill. They worked well, but there were a couple spots I wasn't making progress on and I discovered that a 4" nylon-abrasive wheel really did the trick.

the bristle disc works best on a die grinder..spinning it at 22000 rpm (yes 22k) makes short work of and build up.the cordless drill turns too slow