so.......

in my bike engine mini project ive used a brand new suzuki swift radiator and it work a charm... the thing that doesnt work is the stupid rad cap that I got with it.

Im using a honda bike expansion tank elsewhere in the cooland system so im looking for a method of bunging up the rad cap hole as its spewing water out with the cap on and its not really needed with having the expan tank

I want it to look as neat as possible too..

its black abs plastic. it cuts well.. I was thinking making a tight fit rubber bung and going over the top with sikaflex ??


any help appreicated

bet this won't fit?
Stainless Steel Radiator Rad Blanking Cap For Cars With Expansion Tank

I can't see the rubber bung/sikaflex idea holding for long myself given the heat and pressure.

Could you fit an O ring with the existing cap to seal it better?

try to get a cable tie or 2 around the neck of the cap to stop it moving up under presser

How about cutting an ally disc the same size as the rad neck, sit that on top of the neck with a rubber seal under it, then screw the abs cap on to hold it in place.

You may be able to pull the seal out of the cap and use that under the ally disc.