Thermostat advice

After a two water pump problems in a matter of days with two different cars I own, I need to get a new thermostat for my 94 auto NA.

I went to 2 different places today who both reckoned they had one in stock but comparing it to mine they were both a bit smaller. I am guessing they have looked up supra on their systems and it has given them the UK spec one. Are they different?

I have done a search and the number it seems to be is 90916-03093 for an NA. Can someone confirm this and also if the uk spec ones are smaller than the jap NA ones? Seems more than a co-incidence that both places had the same incorect one in stock.

Also has anyone here run an NA without a stat? I ran mine today and was suprised that the gauge did creep up to about one third of the way after a good thrashing. On other cars I have had they barely lifted off the cold end with the stat out.

Any advice would be appreciated, thanks.

I definately don't recommend running without a thermostat for long, its there to regulate temperature! I would have thought it would be ok for a little while, might get slightly worse fuel economy though

i ran mine without a stat for ages as I was trying to get to the bottom of my overheating problems. didnt do any harm to the car at all.

oh yeah, it won't cause the car to overheat if the stats not in, will just mean it will take forever to get up to temp with the coolant circulating all the time

Yeah thanks. I only put it back together without the stat after the water pump change to see if I had any major probs like compresion getting into the water jacket, that sort of thing. If I could have got a stat today it would have been fitted honest.

So Creative, when you ran yours for ages without a stat how did the temp gauge behave?

didnt do any harm to the car at all.

...that you can see from looking....

Anyway,

Does anyone know if the stat in a uk spec car is slightly smaller than the J spec NA? Can someone confirm that the part no. I have is the correct one for mine? Please:d

Yeah thanks. I only put it back together without the stat after the water pump change to see if I had any major probs like compresion getting into the water jacket, that sort of thing. If I could have got a stat today it would have been fitted honest.

 

So Creative, when you ran yours for ages without a stat how did the temp gauge behave?

sat about 1/4 way up the gauge.....and never moved... until it started to over heat...

...that you can see from looking....

true but with all the tests I did on the car when I was finding the overheating problems nothing turned up. compression was fine etc etc...

then I drove it into a lake and wrote it off....

T R D stats are always selling in ebay

Best thing to do if the stat has failed and you can't find another is to push the stat fully open and drill a hole in it, then put a spilt pin through the hole to hold it wide open. Known as a 'jacked open' stat as used on engine dynos.

That way it gets all the correct coolant flows but can't overheat.

The thermostat is the same on all Supra models, Toyota part number 90916-03093

The thermostat is the same on all Supra models, Toyota part number 90916-03093

Cheers Nic.

This does surprise me though. Both suppliers I went to yesterday offered me the same stat from their listings and it was about 4mm in diameter smaller than the one I had in my hand. The first place I went to said there was two listed and he only had the one he offered me in stock and he would have to order the other in..

Mine has a rubber seal that the stat sits inside of and the ones offered both were too small to use that seal. Am I missing something?

Anyhow I will now order one using 90916-03093.

Thanks again.

Best thing to do if the stat has failed and you can't find another is to push the stat fully open and drill a hole in it, then put a spilt pin through the hole to hold it wide open. Known as a 'jacked open' stat as used on engine dynos.

That way it gets all the correct coolant flows but can't overheat.

That's not a bad idea actually thanks. At least that way I know that the water flow is roughly as it should be. I might do this and try it while I wait for the new one to arrive. Interestingly when I ordered it from Toyota I was asked if I wanted the seal too. Neither of the other places offered me this.

I have the correct `stats in stock. The ones you have been offered are MKIII Supra ones. You need a working, and correct, `stat in it, or it'll use a lot of fuel and run too rich. If you want a `stat ring me.