coolant issue, this will make you scratch your heads?!?

[adam danner]

ok, so the car starts and idels just fine no problems, but as soon as you rev up the engine to any thing about like 4000rpm, coolent just sprays out the overflow tube. Now I know what you are thinking, its a rad. cap, or its a blown HG. i have done a leak down test and the HG checks out just fine, i put a new cap on it an that also does not fix my problem, tonight i used a coolent system pressure tester and it held the 13lbs and there were no leaks. im stumped

I just wana get this issue fixed so i can take my baby to the dyno and get her tuned

So help me if ya can thanks a million guys!!!

 

[dsmburns]

What is your thermostat showing?

 

[talon_swift7834]

I would double check to make sure it's not the head gasket.

 

[jemsoccer]

Thermostat is broke and is not one of those fail-safe ones. It is broken closed. I had this happen in my GST. Amazingly enough, it did not overheat and blow the HG. I was doing freeway driving, so it kept the temp down till I got to my apartment, and my overflow was boiling!! Change that out, and let me know if it is fixed!

 

[95greentsi]

Did you feel the coolant hoses? make sure both the upper and lower hose are getting hot, if not replace thermostat. Also feel the heater core hoses. if both aren't getting hot, the heater core may be getting clogged and if so flush it out.

Did you check the overflow bottle to see where the level is? If its too high, that could be causing your coolant to spray out since at 4000k rpms your building up some pressure.

 

[e85_4g63]

Is your thermostat stuck open? When was the water pump replaced last? Any restrictions in the U/L radiator hoses? When was the last flush and fill? Is your PCV valve in good condition?

 

[bomexe]

take your thermostat out and then try it...that fixed my coolant problem.

 

[sirspoolalot]

i had a really similar problem. if i would give it gas to about 4300 rpm the car would start to overheat, and reach about 90% on the temp gauge. turned out it was just my thermo. i replaced it with a 195 degree thermo from autozone. the car runs fine now.

 

[adam danner]

Ok guys im going to try the thermostat tomm...... The whole enging is a fresh rebuild with only 100 miles on it, rad is new, hoses new, pump new........... i will keep you all posted tomm when i see what happens. Thanks so far!!!!

 

[alansupra94]

If the thermostat gets messed up, it can cause this problem. Seen it in some cars, especially in Windstars and Neons.

 

[adam danner]

well i took off the water neck to take out the thermostat and Boom!! there wasnt even one in it, so im off to the store to get one and put in it to see if that helps.......

 

[jemsoccer]

well i took off the water neck to take out the thermostat and Boom!! there wasnt even one in it, so im off to the store to get one and put in it to see if that helps.......

I'm sure it might help just a little...

 

[alansupra94]

well i took off the water neck to take out the thermostat and Boom!! there wasnt even one in it, so im off to the store to get one and put in it to see if that helps.......

Now the bigger question remains.....where did it go

 

[adam danner]

Now the bigger question remains.....where did it go

I think my neighbors yard gnomes took it while was sleeping..... however i put one in it and the car almost over heated in less then 5 min, and both of the rad hoses, and the rad were cold, but the heater hoses were hot??? i think it may have ben stuck shut, i got it from advance, and i havent had any luck in the past with there thermostats..... i dunno im really starting not to like this car i have had it for over a year and have only put 100 miles on it...

 

[jemsoccer]

Correct me if I'm wrong, but if the there is no thermostat, the coolant will just continue to flow, right? So maybe what you should do is remove that new thermostat, put the thermostat housing back together, remove the cap and pump water into the housing. At the same time, remove the lower radiator hose and see if water begins to flow out the bottom. Obviously, the old stuff is going to first, so be sure you know when it is the fresh water. You may need to block off the radiator hoses accordingly to be sure it flows through the engine. I am not at home right now, nor is my motor in the car, so I can't visualize the paths right now...

There may be an easier way to do this, but sounds like a good way to me. This will just make sure your system isn't clogged anywhere, which is what I'm thinking it is doing. Unless of course the water pump is in fact junk, but it is easier to see if it is clogged than to pull a water pump!

 

[Littlebeeper]

have you tried the pressure tester on the radiator when the engine is on and revved to 4K? maybe the HG is toast but has a small leak to the cooling system. revving high causes the leak to be noticed. i say its the HG. i can rev mine up with no radiator cap and all i get is a gradual overflow out the neck. till the Thermastat open thin it overflows out the filler neck faster but with no real pressure. with a good radiator cap (that may be bad and stuck open to the overflow tube) there should be no overflow till temp is reached. overheating within 5 minutes, check the thermastat in boiling water or replace it again. if thermo is good then we are back to the headgasket.

 

[adam danner]

Cant figure it out guys so i guess im just going to replace the HG and waterpump and cross my fingers!!!!!

 

[Jonny353]

So it wasn't the fact you didn't have a thermostat odd. Yeah for sure replace the HG and see if that does anything for you. Good luck.

 

[eeeewidner]

A couple of months ago I had the same problem with my 92, H.G. most definitely. My cooling system held 15lbs of pressure on a tester for over an hour before dropping. I ended up using a boroscope and found such a mi-nute leak to cause havok....

 

[Littlebeeper]

Did you check the radiator cap? it may be bad and stuck open to allow water to flow out the overflow. like i said earlier, if the engine is revved without a cap and with no Thermostat or one with a safety bypass that allows some flow of coolant incase it goes bad you will get coolant through the overflow really quickly. you may overheat rather quick due to air in the coolant since you've been adding coolant/water for a while since you have been loosing it and testing the system. its a long shot but its free to check the top or cheap and good preventive maintenance since its cheap anyway.

 

[tqmx1]

When you have it apart have the head & block checked for cracks. Some times when the engine is cold the crack will seal it self and when it warms up the crack will open dumping compression into the cooling system.

Also if one piston and combustion chamber is clean and all the others are dirty you found the leaking hole.

 

[98GST6BOLT]

i would def check the head gasket mine was doing the same exact thing and i had to swap the hg, it sucked because i only had about tow hours on the previous head gasket

 

[98GST6BOLT]

also if you do swap the head gasket have your head resurfaced, coudl save you some trouble, only about 40 bucks

 

[Quietkiller]

for everyones knowledge if there is no thermostat in a vehicle, the car will run cooler due to non-stop flow. because you dont have a thermostat in a vehicle, ANY VEHICLE will not cause ANY VEHICLE to run hot. how did you check if its a good hg or bad ? just to humor me, does your fans turn on ?

 

[tqmx1]

for everyones knowledge if there is no thermostat in a vehicle, the car will run cooler due to non-stop flow. because you dont have a thermostat in a vehicle, ANY VEHICLE will not cause ANY VEHICLE to run hot. how did you check if its a good hg or bad ? just to humor me, does your fans turn on ?

So what you are saying is ALL the factorys are putting thermostats in there cars and they don't need them?? So why do they install them? Lets see quicker warm ups (that helps) keeps the engine at a constent opperating temp and to restrict the flow of water through the radiator (it takes a certen amount of time for the water/coolent to transfer the heat into the core) and then out to the air.

No most of the racing classes might not run a thermostat but they slow up the pump and then put a restecer(sp) there the Tstat would be.


To fast is just as bad as no flow.