Are these the correct gaskets (copper rings) and is this where they are meant to go? If not please let me know what type of gaskets i need and where they should go.

Hi
Yes
that is where they go..
between the head and barrel /cylinders..

Lee

cheers mate, thankyou very much

I beg to differ Lee. They are not head gaskets, they are copper seals used on early 40 and 36 hp engines as a secondary seal to the head to 'prevent' combustion gasses entering the heater system on the old non-fresh air style. The copper ring fits around the cylinder down near the cast fins and into a receiving groove in the head. This is on early small bore engines, not the one pictured. On this engine, no gaskets are used, it rely's on the machined surface being clean and flat, some people recommend lapping the barrels into the head to improve the seal, but be carefull to not remove too much material on the head. It is also extremely important to have all the threads of the head nuts and studs retapped, cleaned and lubed to ensure the correct tension is applied to the head when torqued.

Using those gasket, the copper will fail and leak and burn the head/barrel if left for any time. The compression ratio will also be seriously effected.

this is a 40hp 1200cc. And i had already put the engine back together this way and it all seemed fine, no problems at all. But i will keep that in mind.

NO they go on the outer rim of the barrel as per Matt above

Dont put them in the cyclinder head as it will reduce the compression ratio and u will have less power

and now days there NOT used as the barrel is lapped into the cyclinder head to act as a seal

Matt and Dave are dead right they are not head gaskets as Matt says they fit on the top of the cylinder on the 36 & 40 hp and seat in the head recess not in the head

so this is how it goes. I had the engine without the ring in the cylinder heads and the engine would always have small backfires and little popping sounds, nothing serious though. I tried the engine with the rings in the cylinder heads and it ran perfectly, but then i removed them like you guys said and the engine is running crap again. So what should i do?

The problem sounds like the heads have had too much material removed as they may have been reconditioned numerous times. Now the heads are too close together so the inlet manifold is not sealing properly.
Firstly you should be checking the compression ratio, that will tell you if it is high or not. If the CR is high (caused by excessive machining to the head) you need to lower it by installing spacers under the barrels, the size of the spacer depends on how much you need to change it by. Once this is all done, your heads should be in the right place for the manifold to fit properly. If you have a wierd combo of parts and for some reason the manifold doesn't fit, you could modify it accordingly ( ).
You did the right thing as those copper rings don't last long used there. There are copper head gaskets available for 1600 upwards but they won't suit your engine, the best way is to space the barrels from the underside, if they fit, the copper rings would work ok there as they are away from the combustion process.

ok thankyou for your information, i will try and work it all out.

'the engine would always have small backfires and little popping sounds'

The description sounds like an inlet manifold leak and maybe an exhaust leak too, on the other hand a compression leak will hiss on cranking and be a loud Blap when the engine is under load, starting at first only when cold, then all the time as the condition worsens. Very different IMO

You know more than Me Mat

Lee

https://www.classicveedub.com.au/cvd_new/part_detail.aspx?parts_id=16405 
So is this what i would be looking for? and if so, would these sit between the cylinder (where the fins are) and the cylinder head?

They are for 1600 size piston and barrel sets and as such will not fit your 1200 as the page states they are for between the head and barrel.

NO u dont need that CRAP just lap the barrels to the heads



As per Matt above you have a inlet leak in the mainfold system some where did u replace the head inlet mainifold gasket did the old ones out

Yes i realised, it was just an example but i will get the correct size. Thanks mate