Yet Another "Running Hot" Problem

[Grim94GT]

Ive searched all the posts on here Ive learned a few thing but Im still left with a few un answered questions. Hopefully you guys could help me out. I got a 94 GT and its running hot after like 5min of driving. My question is could not running a Tstat be doing more harm than good? Is there anything bad going to happen for not running one? As of right now im running the fans with the ignition on at all times and have no Tstat also drained and flushed the coolant system. Still runs up at the " A L" level on the factory gauge. My next step is to get an aftermarket water temp gauge and go from there i guess.

And if it helps to know its a 94 block with 90 heads, 5 spd, bbk 70mm tb, 90 intake manifold, MSD dist/dist cap/rotor/coil, H-pipe

Thanks for reading

 

[toyman]

You need to confirm the gauge reading. It's possible that the rad is severely plugged to the point that flushing doesn't do the job. Remember it's probably 16 years old. Is the top rad hose hot? It should be if the engine is running hot. Running without a T-stat isn't likely to be an issue in the summer but you definitely don't want to do that in the winter if the rad is working properly. It's not entirely clear about the T-stat. Have you already removed it or are you thinking about removing it?

 

[ivan12]

Run a stock replacement t-stat and shy away from the "failsafe" Mr. Gasket ones. Running a t-stat will help your engine run at it's optimal temp. Run the car cold and your mileage will go down and you'll put extra wear on your internals. Quick question, why are you running 90 heads and who did the install?

 

[rz5.0]

you need a t stat or it will overheat. get a 180

 

[darkhorse21]

i would also agree to get a 180* tstat but also there could possibly be air trapped with in the cooling system. with the trapped air, it will create an increase pressure in temp. by getting rid of it, when cold, start your car with the rad cap off that way the trap air will come out. give the throttle a little hit and youll see bubbles coming. put the cap on your good to go. trust i live in hot south florida weather and it works.

 

[toyman]

you need a t stat or it will overheat. get a 180

Care to explain that logic?

 

[beuchaw94gt]

Well you said that you have different head maybe the gaskets were put on wrong. just a thought.

 

[Grim94GT]

I might of found my answer. My water pump just started leaking yesterday so hopefully it was on its way out and thats why it was overheating.

You need to confirm the gauge reading. It's possible that the rad is severely plugged to the point that flushing doesn't do the job. Remember it's probably 16 years old. Is the top rad hose hot? It should be if the engine is running hot. Running without a T-stat isn't likely to be an issue in the summer but you definitely don't want to do that in the winter if the rad is working properly. It's not entirely clear about the T-stat. Have you already removed it or are you thinking about removing it?

The t-stat has been out since I got the car back in march. And yes the top hose was way to hot to the touch.

Run a stock replacement t-stat and shy away from the "failsafe" Mr. Gasket ones. Running a t-stat will help your engine run at it's optimal temp. Run the car cold and your mileage will go down and you'll put extra wear on your internals. Quick question, why are you running 90 heads and who did the install?

It was like that with those heads when I bought the car. Ive been having a problem with the maf not sure for what year to purchase one for either my 94 or an older year..

i would also agree to get a 180* tstat but also there could possibly be air trapped with in the cooling system. with the trapped air, it will create an increase pressure in temp. by getting rid of it, when cold, start your car with the rad cap off that way the trap air will come out. give the throttle a little hit and youll see bubbles coming. put the cap on your good to go. trust i live in hot south florida weather and it works.

And I will be putting in a 180 when I replace the water pump this week some time..

Thanks for all of the info!

 

[ryclef331]

Check the gasket on your radiator cap...if it torn up in any way, it will release presure and cause a boil over and high temps

 

[john#21]

I had this issue with no tstat. I replaced the oem rad, tstat and ect and all is normal. How old is the rad, Original? May be clogged up.

 

[Grim94GT]

Looks like the original radiator, and has a new rad cap... now I have a new problem on my hands. Stripped the lower blot on the water pump. Now I cant get it off and cant fit a socket in there either, since the crack pulley is in the way.. Any ideas??

 

[ryclef331]

like

Looks like the original radiator, and has a new rad cap... now I have a new problem on my hands. Stripped the lower blot on the water pump. Now I cant get it off and cant fit a socket in there either, since the crack pulley is in the way.. Any ideas??

Like i said in the OTEHR thread you made....take off the dam crank pulley so you can actually get AT the bolt you need to. Its four more bolts and they're the same size.

 

[Grim94GT]

like

Like i said in the OTEHR thread you made....take off the dam crank pulley so you can actually get AT the bolt you need to. Its four more bolts and they're the same size.

Thanks! sorry for posting in another thread

 

[Lee12609]

you MUST run a thermostat or a restrictor plate atleast.

without a thermostat the car will run cool for a short period of time, but the coolant wont stay in the radiator long enough to cool after so long it only gets hotter and hotter. i know this because i just tried it last week on my car. it was fine for 15-20 minutes of cruising, then it started to creep up and up and up. installed a NEW 165? thermostat and all is good. i should say that my car is a 96, is boosted, and tuned to turn the fans on at a lower temperature... just so nobody says "that thermostat isnt doing any good"....

 

[Tbuck07]

you need a t stat or it will overheat. get a 180

Care to explain that logic?

+1

 

[Lee12609]

you need a t stat or it will overheat. get a 180

Care to explain that logic?

+1

i just explained the reason right above your post.

 

[toyman]

I'll take your word for it but it doesn't make sense. What you are suggesting, I'm sure, defies the laws of physics. If what you saying is true then by the same analogy the water is moving through the block too fast to heat up. You can't have it both ways.

 

[Venom351R]

you MUST run a thermostat or a restrictor plate atleast.

without a thermostat the car will run cool for a short period of time, but the coolant wont stay in the radiator long enough to cool after so long it only gets hotter and hotter. i know this because i just tried it last week on my car. it was fine for 15-20 minutes of cruising, then it started to creep up and up and up. installed a NEW 165? thermostat and all is good. i should say that my car is a 96, is boosted, and tuned to turn the fans on at a lower temperature... just so nobody says "that thermostat isnt doing any good"....

It may be tuned for the fans to kick on at a lower temp but the engine is still not operating at an optimal temp. Heat is not always a bad thign its just when there is to much of it but the engine is meant to run between 180-210. Below that the system is always going to be in open loop always trying to cool it down.

 

[Lee12609]

I'll take your word for it but it doesn't make sense. What you are suggesting, I'm sure, defies the laws of physics. If what you saying is true then by the same analogy the water is moving through the block too fast to heat up. You can't have it both ways.

yeah, just take my word for it, or pull your thermostat and give it a shot.... you are partially right though, but its not that the coolant isnt in the block long enough to heat up its the fact that its not in the block long enough to pull the heat from the block. water absorbs heat quicker than it can cool, so it will draw the heat off of something fairly quick (stick a piece of burning metal in water, cools almost instantly.... take boiling water and blow 80+ degree AIR across it and watch how long it takes to cool)...

 

[Venom351R]

lol Im all set w/ pulling my thermostat just so I can see my temps get hotter and hotter. It runs at a cool 180 w/ my cooling set up and Im fine with leaving it that way