Lotus Elan and Lotus Elan Plus 2 Forums

this cylinder head is identical to mine. do YOU know the thread size which i'm showing in this picture: it's 1/2" as i measured but i cant measure the pitch etc.... or determine the type of thread (NP, BPPS???) and want to buy two AN8 adapters to get some oil down to the unused gas pump cover (which will also get one of those adapters) - is this a good idea btw?? sandy

Hi Sandy
It will be BSP.

The plug covers a cross drilling from the exhaust to the inlet side of the head which then drains away. No real need to add more drains I believe.

cheers
Rohan

thanks rohan - cyl. 4 is pushing a bit of oil through the collector-gasket, so it leaks downwards and intend to lead it thru the petrol pump cover back into the motor - using dash or AN 8. if someone has a cross-section area I could see whether it may help?? sandy

Hi Sandy
Perhaps an idea for you.
Me and a few friends had modify the old haeds to eliminate standing oil at the valve.
In my fall the oil that runs down, helps to lubrify the gear from the dry-sump pump.
Greetings Urs

Yes if you have an older style Mk1 head or early mark 2 head ( like in the photo with the drain tube and tapping) without the cross drilling then a drain from the rear of the exhaust cam may help prevent smoking on start up.

cheers
Rohan