James head gaskets

[RonH]

I have a 48 chief and have the old style head gaskets installed. They have not been torqued down yet. I was told to use the James head gaskets along with their gaskets for the primary also. Any info would be helpful, Thanks in advance.

[1950Panhead]

You can use copper or fiber head gaskets, it is important to retorque after engine has run as original head bolts stretch.
I'm using grade 8 head bolts.

[T. Cotten]

Ron!

It is far more critical that your heads and cylinder decks have been dressed flat, than your choice of gaskets (although I would avoid copper with an aluminum head).

Beware that it is common for the cylinders to warp over the intake ports, even though they are cast iron.

....Cotten

[exeric]

For what it's worth, I've always doused head gaskets with high heat aluminum paint, and assembled the head while the paint was tacky. I've never had a blown head gasket on an Indian. Tom's advice is well worth heeding.

[T. Cotten]

I agree Eric,

Conventional composite gaskets soaked up heat paint nicely, but please note that JAMES are already impregnated with their own adhesives.
Paint defeats them.

The most difficult part of re-torquing Chiefs in the chassis is the arsenal of extentions it requires. But at least the tanks need not come off!

....Cotten

[PRG]

Howdy chaps,

And the problem with using copper with an aluminum head?

The main reason for hideously high torque values for these and Fours is to address burn-through on fiber gaskets. Having seen the ruinous effects of 50lb ft plus head bolt torques on Fours wherein the washer land areas began to collapse I carefully dressed both surfaces on my 440, installed copper gaskets and torqued to 30 ft lbs, a figure used for air cooled Porsche head bolts. That was 21 years ago and haven't touched them since, this machine will be sitting in front of Rocky's tent at the horse barn if anyone wants to inspect for evidence of carbon tracking.

[T. Cotten]

Peter!

I admit that the copper for cast iron/composite for aluminum is a harley thing.
Those aluminum heads that I pulled out of barn piles with copper gaskets showed erosion.

The only modern headgasket that I ever had fail was copper, and it blew bubbles before the motor was even started.
If they depend upon a paint or sealer, then why have a gasket at all?

Avoid extreme heat, and anything should stay sealed.
But one question that never has been answered to my satisfaction is: Do we want to insulate with a gasket, or conduct?

....Cotten

[PRG]

Howdy Cotten,

Head gaskets figure into some engine's desired compression ratio and in OHV motors occasionally valve to piston clearances. David Kilgore who rode his 47 Chief well over 100k miles in a decade built a hot rod 80CI motor with no head gaskets. Ran like stink but adding that bit of compression to cams and other mods meant a far shorter life afflicting the area for which most flat heads suffer: heat rejection at the exhaust valve area.

Speaking for head gaskets only, fiber gaskets thermal properties can be measured in resistivity compared to the conductivity of copper. Without benefit of oil in the head to carry heat away from the exhaust port/valve exacerbated by having that valve reside in and surrounded by a mass of iron anything one can do to wick heat away will benefit a flathead or IOE immensely. 38-42 Fours add to this thermal burden by having a thick heavy iron header attached. Exhaust valves can get so hot on these they will run on with the ignition off. To ensure as much heat transfer as possible I do not use any gasket glues, rather ensure the mating surfaces absolutely flat as possible.

[T. Cotten]

So Peter!

What are you suggesting for Ron?

....Cotten

[rousseau]

Ron
I don,t know about your Indian, but almost all British (Norton,Triumph,BSA) bikes use copper head gaskets with aluminum heads. Always be sure they are annealed and coat them with a thin flim of grease (I use vasoline) when installing. This is from my various British service manuels.

[PRG]

Howdy Cotten,

Going to speak to the first timers as you know this already. If valves out surface plate decks and heads. On shear cut copper gaskets I flat the sides where the shear has slightly rolled the edge over. Lay the head on top of the gasket on a flat surface and measure the depth of each head bolt hole. If using original head bolts or some of unknown origin I number them on the heads in a circle and run each down into the cylinders prior to fitting the heads and gaskets to ensure none will bottom out before achieving desired torque. With no idea of the stretch to be achieved on 70 year old bolts at 50ft lbs plus leave a generous margin on depth. You want to chase the threads in your cylinders to remove carbon and clean the bolt threads as well to ensure accurate torque achieved. If having done that and you cannot run a bolt down into the cylinder by hand it has likely stretched and is compromised.

Bolt vs head depth is critical on 38-42 Fours. 75 years of clamping pressure on heads with additional depth on the rocker box side to crush will have resulted in more settling. Bottom bolts out on these and not only will the gaskets fail into the rocker tunnels or between cylinders in some cases the cylinders will crack laterally between the first couple of cooling fins.

[T. Cotten]

Thanks Peter, and Folks,..

I know this is a contrary observation,
But after witnessing 'modern' auto headbolts stretch purposefully (never intended to be re-used),
and witnessing thoroughly modern reproduction H-D headbolts stretch to the point of fear,
I am amazed at how re-useable both H-D and Chief headbolts have have proven themselves.

But then, I have used a torsion torquewrench religiously.

The poor compressibility of copper, from my perspective, punishes the rest of the hardware.
Once again I ask: If there is a justification for un-forgiving copper, is it because we want the heat of the head conducted to the cylinders?
That seems incredibly counter-intuitive to me!

Thanks in advance as always,

....Cotten

[pisten-bully]

waiting...watching... curious to know here, too. Could be related, but why were cylinder heads changed to be made of aluminum? Better, as in quicker, heat dissipation? Better suited to casting with thinner fins, therefore more fins? Reduction in engine weight?

[RonH]

I agree on why were the heads made out of aluminum! I have been told by a few that you have to re-torque the head bolts after the first start up and then at around 50 miles. I used the James gaskets on my shovel when I had it yrs ago with no problems. The gentleman who rebuilt the motor was a retired machinist, so I do believe he did check all the surfaces to make sure they were flat. The head gaskets I have are gray in color and have a texture on them. The name is Beck Arnley. I am attaching a pic.
FullSizeRender.jpg

[1950Panhead]

But one question that never has been answered to my satisfaction is: Do we want to insulate with a gasket, or conduct?

As the fuel burns heat is transfered from inside to the head and cylinder.
If the head is aluminum and the cylinder is iron the aluminum head can transfer heat into the air faster then the iron cylinder.
If you have copper gaskets the heat can move from the cylinder to the head then to the air.
If you have composite gaskets the heat transfer is inhibited and stays in the cylinder.
I miss you Cotten! I post these days on the board you don't like.
Jerry