Worn Radiator Filler Neck

I have been having some issues with water disappearing from my cooling system. I used a pressure tester and can't find any leaks.

I did notice however when I put the radiator cap back on I could pull the radiator cap off with my fingers. Even after adjusting the tabs I couldn't get it to stay.

It seems that the filler neck to the radiator has worn. I can get the cap to seat with about 3/4 turn and it wont come off but I was wondering if there is a quick fix until I get a chance to replace the radiator?

Worth putting some plumbing tape round the neck thread to help hold the cap on?

Cheers
Chris

 

it is possible you just need a new radiator cap.

 

My old radiator had the same problem and would leak out the cap. It only did it after I fitted a new cap ?. put the old one back on and never leaked. you could always try squeezing the tabs in with a pair of multi-grips to tighten it down.
Cheers Dave

 

Take caution with this, mine was worn the same way when I ran my old stock TT rad. Ended up leaking under pressure no matter what cap I had on there or how I tried to modify it & every third day temps would start rising due to coolant loss. My advice is bin that radiator before it costs you a rebuild & at least purchase an eBay 56mm alloy one as I did that runs rings around the shitty old stock ones.

 

so I would most likely follow the advice of those who have had this issue as well.

 

Just want to follow up on this thread.

I changed the radiator cap for $10 and my cooling system is all working properly, the first time in months that the water level hasn't dropped.

Sometimes the simplest/cheapest things fix the problem.

Cheers for the help

Beavis

 

you are welcome glad we could help.