Met a fella today and he's told me his 03/05 warrior keeps cooking the thermostat, he's not sure why, any ideas?

Has he tried removing it from the oven?

Daz

Needs flush, faulty/cheap part, fitted upside down , there are two types of thermostat ratings for these trucks I think, water pump not working correctly

Get him to run without the stat for a while and see if the problem still occurs, is he overheating ?... is he losing coolant.?
Has he still got the EGR and cooler on ?

Is he putting the stat in the correct way around?

Cooking the stat > U mean overheating the truck?

Boil some water in a pan, put a thermometer in it that water - when the water is at the correct temp (not sure what that for the l200 somewhere near 75-85 deg c probably) Put the Stat in water - can you see it open???

> Make sure the water is a few deg hotter than the normal opening temp as it will vary from stat to stat - if the manual states it opens at 80 deg c
Just to make sure it works - I would try water at 90deg as it will take a while to heat the stat to that temp in the water and the water temp will drop for a basic test.. if it does not open - bin it!

Some vehicles that are prone to air locks and will overheat if not bled properly - not sure how the l200 factors??? sorry.
I am sure others members will have a better idea... the things I work on require bleeding but they are a bit different.

Egr and all still on, didn't say much about trucks behaviour, I'll get him to try a few things mentioned. Thanks folks