Running cold issue. Tricky one-thoughts needed

[snapdragon]

Originally Posted by ainarssems

Just a guess- maybe it is getting twisted/squeezed when fitted in housing which restricts free movement?

Also once the thermostat I tested in boiled water seamed to work correctly and I only noticed that it is not closing properly later. It was hard to see because of the shape but it always stuck little open about 1.5mm but what are the chances of it happening with 2 new thermostats.

Thanks, this is a thermostat that comes as part of a larger plastic housing with outlet pipe to radiator. I suppose a bit like the metal housing of the older V6s but with the thermostat built in. When it was closed it was air tight, I could put the pipe in my mouth and blow until my eyes popped out.
Once hot I could blow easily.

The second time round, I was very careful on fitting (which is quite easy anyway), such as not to knock the moving parts.

I'm now starting to think this is normal for a modern diesel.
Maybe removing the DPF and catalyst had some effect on running temp.

Next, I will try disconnecting the radiator fans and if that doesn't work I can't see what else it could be, as it runs like a dream, so I can't suspect retarded injection or anything that drastic.

CLOSED....


OPEN....