I need something with an M20x1.5 thread to use to plug the oil cooler ports on my engine.

Any ideas? A sump plug perhaps? Would like to avoid ordering & waiting for some expensive bits from my local fastenings place if there's a cheap/plentiful alternative.

Halfords have a range of sump plugs - not sure if they will be big enough though.

Stu

rpi in norwich do the real thing for the job around a fiver each and they have an o ring on them ,this is for the serp cover i take it to blank off the cooler

m20 1.5 is conduit thread
try local electrical wholesalers

Thanks for the ideas.

Froggy, you're correct - I have the intermediate serpentine front cover on my V8 which includes 2 oil cooler ports. I hadn't tried RPi, but I did speak to a chap at Rimmer Bros who was pretty useless and incorrectly told me that I couldn't blank off the holes without killing oil flow.