Thermostat

[flyingspanner]

My surf cooked and cracked its head the cause of this was the thermostat,it opens at 88 c but testing it by boiling,it opend at 98 c!!! now is there any problem with leaving it out after the rebuild

[icsys]

Howdy flyingspanner...
I'm facing the same problem... It says 88c but my stat wont open at all so contemplating the same thing.

[TonyN]

it won't hurt for a while, but the 'stat regulates water temp all the while your driving, and coolant temp is measured all the time for fueling settings by some EFI motors, so you may be running too cool sometimes and getting odd mpg or performance.

So get a new one if poss.

[Muzz67]

Thermostat is necessary

They keep the engine running at a constant temp, and if you don't have 1 it can take 15-20 minutes for the donk to reach proper running temperature-no interior heater!. Also , it can stop an auto trans from up-shifting as the electronic brain senses the cold engine isn't ready for load yet.

[icsys]

Hi Tony,
I notice on the stat that it appears to be dual action in that as the main part opens to let coolant to the rad, a small plate appears to close off a pipeway at the back. Am I right? Do you know where this pipeway comes from / leads to?

[TonyN]

Hi Tony,
I notice on the stat that it appears to be dual action in that as the main part opens to let coolant to the rad, a small plate appears to close off a pipeway at the back. Am I right? Do you know where this pipeway comes from / leads to?

Nah, thats different to our 4Runner, it may be a bypass to get water somewhere important (like the head) even if the stat is shut.

Was a bit early in the morning for that techincal post, should also have put that another issue with no stat is that if you shift water through the rad to quickly it doesn't stay in there long enough get cooled enough, leading to overheating.

So take your pick, to hot or to cold! depends on the engine design!

Better of with a stat in general!

[Guest]

Nah, thats different to our 4Runner, it may be a bypass to get water somewhere important (like the head) even if the stat is shut.

Was a bit early in the morning for that techincal post, should also have put that another issue with no stat is that if you shift water through the rad to quickly it doesn't stay in there long enough get cooled enough, leading to overheating.

So take your pick, to hot or to cold! depends on the engine design!

Better of with a stat in general!

Yeah it's a bypass, that's the main reason for using the correct thermostat. Leaving the stat out for a long time will likely cause you problems. one of the other reasons is that it restricts flow through the engine to allow the water to absorb the heat, if it isn't there the water can circulate too quickly under the action of the pump and the engine may in fact run hotter.

Cheers

[crusty]

it restricts flow through the engine to allow the water to absorb the heat, if it isn't there the water can circulate too quickly under the action of the pump and the engine may in fact run hotter.

Cheers

I don't mean to be picky, you're kind of correct, but kind of backwards. Too much flow doesn't allow the coolant long enough in the radiator to cool before it gets pumped back into the engine and reheated. Heat sink (from the engine) into fast flowing water will be greater than in slower moving water of the same temp.

PS.Do we get higher post counts if we use more punctuation?????.

[Guest]

I don't mean to be picky, you're kind of correct, but kind of backwards. Too much flow doesn't allow the coolant long enough in the radiator to cool before it gets pumped back into the engine and reheated. Heat sink (from the engine) into fast flowing water will be greater than in slower moving water of the same temp.

PS.Do we get higher post counts if we use more punctuation?????.

Yeah you're right, got it a** about. Had a long day. Same effect though, too fast will cause you a hotter engine.

Cheers

[crusty]

Sorry mate, there's nothing worse than a smartarse noobie
I knew what you meant. I was just bored at work.

[Guest]

Sorry mate, there's nothing worst than a smartarse noobie
I knew what you meant. I was just bored at work.

No offense taken - sometimes I talk out of my a**e anyway. It was a good point to clarify though

I'm not sure actually that the lamps on the front actually cause many problems (I took min off though) as I still think that removing the hot air via vents in the bonnet will make a much bigger difference. It's just that the Surf engine bay is so cramped that the air can't get out so it sort of prevents new air getting in. If you vent the bonnet then you can get more air through the radiator and more hot air away quicker.

I'm going to fit some Cossie / Scooby style vents in mine eventually.

Cheers

[JimL]

Anybody have the Toyota part no. for a new thermostat on a 2.4???
Handy not to have to look at them frowning when you say 'surf'...

Thanks

[icsys]

I dont know about the original Toyota stat (£15 I believe) but 3rd party alternatives sourced at my local car shop are 2 made by Quinton Hazell Automotive Ltd:
QTH321 88c and QTH322 82c Both are identical except for the temp.
£9.95 each.

[tich]

Mornin!
Just finished boiling two stats. Both were suspended in water so they didn`t touch the sides of the saucepan. Using a digital thermometer one opened at 87c the other at 92c (both had 88c stamped on them). Have just phoned Toyota and as far as they know they think that the stat should open at around 82c.
One of the stats I had was the one that was in my Surf when I bought it the other I got from a foriegn autoparts outlet. To try and do the right thing have ordered one from Toyota (£13.25).

FINGERS CROSSED!!!!!!!!!.

Regards
Tich

[andy]

Mornin!
Just finished boiling two stats. Both were suspended in water so they didn`t touch the sides of the saucepan. Using a digital thermometer one opened at 87c the other at 92c (both had 88c stamped on them). Have just phoned Toyota and as far as they know they think that the stat should open at around 82c.
One of the stats I had was the one that was in my Surf when I bought it the other I got from a foriegn autoparts outlet. To try and do the right thing have ordered one from Toyota (£13.25).

FINGERS CROSSED!!!!!!!!!.

Regards
Tich

If one opens at 87c then that should be the one to fit , I believe that the 2.4s are fitted with the 88c stat , and the 82c is the one fitted in the 3.0 models , all of the 3.0 surfs that I have bought had the 82c stats in them when I serviced them , so that is what I replaced them with .