Head gasket

[Nikhil Bhale]

As a Marine Engineer who has worked on many big engines of 25000 bhp and more I have seen engines without a head gasket or gaskets for fuel valves (injector).
The seating areas are lapped with special tools provided and parts are assembled without any gasket, liquid or solid.
The cylinder head nuts are hydraulic tightened by stretching the bolt with a special puller and then tightening the nut by hand. Nuts are round with drilled holes around the circumference to apply some torque by a small 6" tommy bar.

 

[minh-thanh]

As a Marine Engineer who has worked on many big engines of 25000 bhp and more I have seen engines without a head gasket or gaskets for fuel valves (injector).
The seating areas are lapped with special tools provided and parts are assembled without any gasket, liquid or solid.
The cylinder head nuts are hydraulic tightened by stretching the bolt with a special puller and then tightening the nut by hand. Nuts are round with drilled holes around the circumference to apply some torque by a small 6" tommy bar.

View attachment 144413

But no one has that machine
Homemade engine just need flat surface and head gasket is good enough

Hi Gordon
I don't know if there is enough room to drill more holes for bolts?
If you still have it, you can do it like this
Whatever the solution, the surface must be flat

 

[Gordon]

I am still working on this from time to time until I get frustrated and move on to something else. My solution is ultimately going to be adding two more head bolts in the valve area as you suggest.

I have been trying to work out an ignition system to fire both cylinders using a wasted spark but I have reached the conclusion that I either need two ignition modules with separate input signals or a distributor. Two magnets 50° apart makes one cylinder fire at the correct time and the other cylinder fire part way into the compression cycle. The engine kind of tries to run even with the leaking head but it is basically just running on one cylinder.

I am going to have to learn how to concentrate on one problem at a time instead of moving from one frustration to another frustration.

 

[minh-thanh]

Gordon !
.... I haven't made that engine yet so with my little experience...
If you have the last option of using bolts then do it , it will save your time and effort ... . That's also my choice in this case.

 

[kf2qd]

2 bolts are not going to allow much pressure for sealing.and that intake port close to the edge doesn't make it any easier.

 

[Gordon]

I have placed two additional screws in the valve area and I no longer have a leak at the head when using a teflon gasket. Still having a problem getting enough compression to run even using O rings. Valves are sealing and there does not seem to be leakage around the piston but still not enough compression to run. Engine is 3/4 bore x 1" stroke. Obviously I am missing something.

 

[minh-thanh]

I have placed two additional screws in the valve area and I no longer have a leak at the head when using a teflon gasket. Still having a problem getting enough compression to run even using O rings. Valves are sealing and there does not seem to be leakage around the piston but still not enough compression to run. Engine is 3/4 bore x 1" stroke. Obviously I am missing something.

Not enough compression or your engine can't draw fuel ?

Make & break wont run

Hello, I am a retired auto technician and have worked for 40 years in the auto industry, most recently as a Master Toyota Technician. I know engines and what makes them tick. That being said….. I recently built a freelance 1 cyl. make and break engine. It is a 1” bore and 1” stroke. I purchased...

www.homemodelenginemachinist.com

 

[Nikhil Bhale]

Hi Gordon,

What engine is this? Is it your own design or is it of some proven design?
If the clearance volume is high you will not get a good compression even if there are no leakages. Compression ratio is ratio of clearance volume to swept volume.
Using a thick head gasket will increase the clearance volume reducing compression.

Regards
Nikhil

 

[Peter Twissell]

I assume you meant to say compression is the ratio of (swept volume PLUS clearance volume) / clearance volume...

 

[Nikhil Bhale]

I assume you meant to say compression is the ratio of (swept volume PLUS clearance volume) / clearance volume...

Yes you are right. I should have said ratio of total volume (Vs +Vc) to clearance volume Vc.

regards
Nikhil