Genuine Nissan Thermostat Not Working

[Interloper]

i need some ideas on the following:

I've put in a new nissan thermostat recently (RB20) to replace my old one that had apparently seized up and stopped working. I mean that it was not letting water circulate through the radiator and so the lower radiator hose was stone cold despite the top one being quite hot and water temps on the PFC showing 95 degrees. Normal water temps for my R32 were about 78-80.

So i put in the new thermostat and the problem is still there! But i've tried running without a thermostat at all and the temps barely get to 60 after a 1/2 hour of driving in the city. So the water pump is circulating water through the radiator (40mm just jap) just fine when there is no thermostat at all.

Could it be a case of a faulty genuine thermostat? Nissan say they tested it and refuse to give me another one....

Before the stock thermostat seized up the car was running perfect for the last few years. It's not like it is a gradual build up of gunk in the cooling system, it worked fine on the way to work and on the way back stuffed itself!

i've flushed to radiator and block and the water was pretty clean with no rust at all. And i've got a new water pump installed too.

Can anyone shed some light on this?

[battery]

you can test it yourself, boil some water and drop it in see if it opens, works best if you have some type of thermometer to check the water temp..

if it test's fine maybe you installed it wrong, maybe too much gasket glue or something....

[lachlanw]

or put it in backwards .....

[Interloper]

yeah, i tested the old one and it opened. But i've been told by a mechanic that its different if it gets hot from both sides like when you drop it into a jug of boiling water compared to just one end when its installed in the car. In the car it would only heat a specific area of one side.

and no, i installed it fine. just like the factory one and no gasket glue was on it when i pulled it out to take to nissan. Which reminds me i should go back to nissan and get that new one back before they forget about it....

[lachlanw]

yeah justa possibility .

really cant see how dunking it in the jug is any different from it being in the ingine . every thermostat ive ever dunked in boiling water has opened

[battery]

dunk it and tie some string around it to keep one side out??

[76GTR]

hi, When you installed the new thermostate did you have the small air bleed valve at the top? maybe the cooing system had a air pocket behind the thermostate. It does happen sometimes

Cheers

Clynton

[Interloper]

hi, When you installed the new thermostate did you have the small air bleed valve at the top? maybe the cooing system had a air pocket behind the thermostate. It does happen sometimes

Cheers

Clynton

yeah, the nissan thermostat has a arrow indicating where the top of the themostat should be positioned, which is next to the little air valve. The factory manual refers to it as a "jiggle valve".

[mad082]

umm, i can't see how heating the thermostat from both sides can make it open differently to heating it from 1 side. only 1 side of the thermostat controls the opening of the thermostat, so dunking it in water is fine. and besides, that's what the nissan workshop manual says to do.

could possibly be the new water pump that is the problem. it may pump coolant with no thermostat but the added restriction of the thermostat may be too much for a weak pump. also there will be a small amount of flow even without a water pump.

[frozenwaffles]

i have a question here, when did you change to the justjap radiator? i am having similar problems, but they only started when i changed to the justjap 40mm radiator. i run a tridon 77deg themostat. R33 gtst

[Interloper]

i have a question here, when did you change to the justjap radiator? i am having similar problems, but they only started when i changed to the justjap 40mm radiator. i run a tridon 77deg themostat. R33 gtst

i've been running the justjap rad for over 2 years no problems.....i might try another thermostat to see if the one i got from nissan is faulty.