I am about to change (by myself) the vacuum pump of my Focus Mk1 1.8 TDDi .

Decided on second hand pump and ordered replacement gasket / O-Ring.


Now i saw gaskets being ring only, ring with one "ear" and ring with two "ears".



The one i will receive is with two "ears".

Should i clip them?
What's the purpose of them?

I saw some replacement pumps with groove for one ear of the gasket but some not.

?

Thanks!

Igor

Thanks.

PS: Here link from an online workshop manual for Ford Focus Mk1 - how to replace the Vacuum Pump step by step ---> LINK