2.5TDI Wrong coolant radiator.

zunnde · Post by **zunnde** » 24 Apr 2025, 05:28

I have accidentaly bought the wrong coolant radiator for my 1999 2.5tdi, the new radiator doesnt have the overflow hose port.
The question being - can i block the hose coming from the reservoir, or will this affect the correct working of the cooling system?

Post by **scot850** » 24 Apr 2025, 08:38

That hose is to allow coolant to return to the coolant header tank. Some versions do not have this. However, they have a breather pipe on the thermostat housing if I recall. However, as we don't have diesels over here I can't advise how important it is on one, but would suggest it is required. Otherwise see is you can find a thermostat housing with the pipe on it as that may fix the issue.

The last option is to add an overflow pipe. There are threads on where that pipe has broken off and people have used various ways to repair it that may work.

Neil.