Type 65 / Nippy Cylinder Head Gasket

[Colin Wilks]

"I'd be interested to know what the perceived benefits are of the solid copper gasket (apart from the fact it can be reused after annealing)."

Better mechanical strength, and better heat transfer, a bugger to seal the water ways though!

Ian, I am getting one of your gaskets from Martin Baker and proposing to assemble with a smear of grease on both sides. Knowing that sealing the waterways is a bugger is interesting, but not quite so much as knowing how you resolved the issue would be. Any chance of some enlightenment?

[Ian Williams]

Martin had some of the copper asbestos gaskets which are basically the same as those available in the UK but to sports pattern. I was referring to solid copper being a bugger to seal, but that said the modern C/A gaskets can be a pain too, Hylomar spray seems to be the best solution to the problem that I have used, others may have their own solution

[Tony Press]

[quote pid='7350' dateline='1519319797']

I think you're right John, but I understand those for the 65 and Nippy are different to the later h/c gakets. Be interesting to know if anyone has used the 36 to 39 high compression gasket in a 1934 Type 65 without problems. I thought the intrusion of these gaskets into the combustion chamber lead to pre ignition, but I may be making that up?

[/quote]

Coming back to this comment about gasket protrusion into the combustion chamber causing pre-ignition.

It is my understanding the cylinder head temperature during running can reach a maximum of around 400 C at which temperature copper can possibly glow a dull red.

I wouldn't think this could cause pre-ignition, so a miss shaped gasket is not a major problem as long as it seals both water and combustion.

Any comments ?

Cheers, Tony.

[Colin Wilks]

Film of a demonstration of ignition temperatures from 1948: https://youtu.be/yG0rP3D_0-s

Other sources quote the ignition temperature of a flammable mixture of petrol and air (1.4 to 7.6%) in a range between 230 and 280°C (https://hypertextbook.com/facts/2003/Sha...pher.shtml)

[Tony Press]

Film of a demonstration of ignition temperatures from 1948: https://youtu.be/yG0rP3D_0-s

Other sources quote the ignition temperature of a flammable mixture of petrol and air (1.4 to 7.6%) in a range between 230 and 280°C (https://hypertextbook.com/facts/2003/Sha...pher.shtml)

With the suggested C temperatures below I would think that some other parts of the combustion chamber could 'spark' auto ignition then (or am I totally confused) ?

1. Intake manifold : 60
   
2. Intake valve : 250
   
3. Spark plug : 600
   
4. Exhaust valve : 650
   
5. Exhaust gases : 450
   
6. Piston face : 300
   
7. Cylinder wall : 185
   
8. Piston ring : 220
   
9. Piston skirt : 190
   
10. Coolant : 105
    
11. Engine oil : 70
    

[Colin Wilks]

Film of a demonstration of ignition temperatures from 1948: https://youtu.be/yG0rP3D_0-s

Other sources quote the ignition temperature of a flammable mixture of petrol and air (1.4 to 7.6%) in a range between 230 and 280°C (https://hypertextbook.com/facts/2003/Sha...pher.shtml)

With the suggested C temperatures below I would think that some other parts of the combustion chamber could 'spark' auto ignition then (or am I totally confused) ?

1. Intake manifold : 60
   
2. Intake valve : 250
   
3. Spark plug : 600
   
4. Exhaust valve : 650
   
5. Exhaust gases : 450
   
6. Piston face : 300
   
7. Cylinder wall : 185
   
8. Piston ring : 220
   
9. Piston skirt : 190
   
10. Coolant : 105
    
11. Engine oil : 70
    

If you accept the assertion in the article's last paragraph "[color=rgba(0, 0, 0, 0.92)]The flammability range of gasoline is between 1.4 and 7.6%. If the ratio of gasoline to air is less than 1.4%, then the mixture is to thin to burn. The mixture cannot burn when it contains more than 7.6% gasoline because it is too rich to burn." then perhaps it is only when the charge has started to be compressed that it falls within the flammability range?[/color]