Expansion/radiator cap problem

The other day I noticed the temp of my 1.1 starting to creep over the half way point (normally sits just below or on the half way point). It went as far as three quarters then sat there. When I pulled up a junction I noticed puff of steam and pulled over to have a look. Water appeared to have escaped form the radiator filler cap and sprayed around the engine bay. I assumed the cap may be faulty and running at 70 mph+ had increased the engine/water temp casuing escape :dontknow:

I topped the rad up with half a litre of water and drove another 10 miles or so. I noticed as long as stuck at about 50 the car temp stayed at about midway. I made a quick fix with some PTFE tape round the filler thread at B&Q. This appeared to have fixed it for the moment, have driven another 60 miles or so and car has behaved as it should with temp staying where it should, but not sure what had caused this problem. Could there be blockage in my water system (although all seems alright now) or has expansion cap just gone past it best?

Cheers

Are genuine radiator caps still available? Has anyone tried a GSF or ECP one - asuume they are pattern :dontknow:

Cheers

Think VW still do them

If you were running fast (motorway) and coolant escaped, suspect the pressure release valve in the rad cap - old-design ones are black, and are prone to failure, replacement ones are a better design and are blue.

If you were stuck in traffic when the engine got hot enough for coolant to escape, suspect the sender in the radiator body (nearside, near the bottom of the rad body) - when tired, it won't turn the fan on (soon enough) in traffic and, with no air passing through the rad, overheating is guaranteed.

Cheers - is a old black style one and plastic does feel a bit hard. The water escape only seems to happen at 65mph+ , which is quite fast in a 1.1 . Seemed ok if I did not exceed 40-50mph.

Cheers

Got hold of a pattern one at the weekend and seems to have done the trick .

Cheers