NEED HELP! coolant evaporating?!

[bird man]

OK guys please help me out on this. I have a 99 GST with a PTE DBB 50 trim and everything to go with it. the car runs absolutly perfect. No ECU codes are present. NO leaks anywhere. I have a 4 layer metal head Gasket with no white smoke coming out the exhaust! BUT I DRIVE 100 MILES AND OVERHEAT BECAUSE IT SEEMS LIKE THE COOLANT EVAPORATED there is tons of preasure, the overflow bottle starts shaking and bubbling... i take the cap off the radiator nd it seems 1/2 empty can anyone tell me what the problem might be? Once i fill her back up (usually a gallon) she runs perfect again. i can drive across town about 30 miles and my bottle will be almost empty and i will have to fill it back up. as long as i keep putting water or coolant in the bottle before its empty the car will never overheat. but im because its not leaking anywhere but the water just evaporates?????? please help.

 

[bird man]

OK guys please help me out on this. I have a 99 GST with a PTE DBB 50 trim and everything to go with it. the car runs absolutly perfect. No ECU codes are present. NO leaks anywhere. I have a 4 layer metal head Gasket with no white smoke coming out the exhaust! BUT I DRIVE 100 MILES AND OVERHEAT BECAUSE IT SEEMS LIKE THE COOLANT EVAPORATED there is tons of preasure, the overflow bottle starts shaking and bubbling... i take the cap off the radiator nd it seems 1/2 empty can anyone tell me what the problem might be? Once i fill her back up (usually a gallon) she runs perfect again. i can drive across town about 30 miles and my bottle will be almost empty and i will have to fill it back up. as long as i keep putting water or coolant in the bottle before its empty the car will never overheat. but im because its not leaking anywhere but the water just evaporates?????? please help

[Whatever it was that made you think this deserved two, identical threads, was wrong.]

 

[carsaval]

do you have an autozone in your location, if so go rent a radiator compression tester, Just to see.

 

[King Salami]

Replace your radiator cap - the seal is probably shot.

 

[olmytsi]

Could be your cooling system (rad cap, rad etc), a blown head gasket, or your turbo since it's water cooled.

 

[nikulabs]

How hot has it been in las vegas lately? Does it only happen when you drive in town or does it also overheat when you're on the highway as well. My radiator fans on my 1g wouldn't turn on over the summer and I overheated if i was driving slowly. Traced it to a bad thermoswitch. Maybe your FMIC restricts the amount of air passing over the engine if your radiator fans aren't working?

 

[Mitsu RacerX]

Ok here we go. Your HG might be going bad around the water jackets. Which in turns let hot air into the cooling system and makes the coolant evap. Mine did this until I retorqued the HG back down. Try this it might help.

 

[blackbyrd]

I'm sorry, I had the same problem. I would make it 100miles before i'd loose enough coolant through backpresure into the overflow, before i'd overheat.
It was the headgasket. I had no mixing, and no smoke.
You can pressurize your coolant system to test for a "leak".
Try retorqing your head back down ^^

 

[bird man]

thanks guys. ill try the radiator compression test. im pretty sure it ok tho cause we just put in a new dual core but ill try anyways. if not...i guess the head is comin off again!

 

[bird man]

well i know for sure its not the cap. we replaced it twice and also replaced the thermostat just in case. im gonna re torque the head bolts tomorrow. does anyone know what specs to torque them to and if there is a certain sequence to do so?

 

[bird man]

does anyone have torque specs and sequence for the head bolts?

 

[blcknspo0ln]

Are you using ARP's or stock headbolts?

I follow the shop manual sequence and torque in a 30-60-90 ft/lb order with ARP moly lube. With ARP's and regular oil (use really thick oil) I would go 40-80-110. stock headbolts are depending on if they are 6 bolt or 7 bolt. 6 bolts are standard bolts and torque in a specific sequence (can't think of torque numbers off hand) and 7 bolts are stretch type. You need to torque a 7 bolt head bolt down and then turn another 1/4 turn (again can't remember torque spec).

 

[2bclutch]

Air in the system? May need to burp the radiator?

 

[blackbyrd]

Air in the system? May need to burp the radiator?

Maybe, you could have an air pocket. Dunno, if it'd keep reproducing these results though. How did you fill it up?
Did you fill it up and squeeze the upper and lower radiator pipe? Then run your car with your radiator cap off, until the thermostat opened?
Have you tried replacing your radiator cap?
Have you checked to make sure your fans turn on?
Have you checked the operation of your thermostat?

 

[blcknspo0ln]

If you think you have air in your system, just take the rad cap off with the car COLD. Then turn the car on and let it idle for 15 minutes. This will cause all of your air bubbles to come out of your system. To me, though, it sounds like a bed headgasket or coolant leak somewhere.

 

[92awddsm]

Are you using ARP's or stock headbolts?

I follow the shop manual sequence and torque in a 30-60-90 ft/lb order with ARP moly lube. With ARP's and regular oil (use really thick oil) I would go 40-80-110. stock headbolts are depending on if they are 6 bolt or 7 bolt. 6 bolts are standard bolts and torque in a specific sequence (can't think of torque numbers off hand) and 7 bolts are stretch type. You need to torque a 7 bolt head bolt down and then turn another 1/4 turn (again can't remember torque spec).

These are the torque specs for 6 bolt arp headstuds, not 7 bolt. If I remember correctly, 7 bolt head studs have a max torque of 75ft/lbs using oil. If you have stock head bolts, dont try to retorque them. They are torque to yeild and will stretch considerably to the point of no clamping force or worse yet, break. If they are stock, replace them with studs, one at a time following the stock torque sequence.

Also as stated, pressure test the coolant system for leaks. If none are found, buy some uv coolant dye and see if you can find coolant seeping while the engine is running. Next step would be to flush the coolant system, replace the rediator cap, and thermostat also. Since you havent noticed a leak, I am willing to bet that the radiator cap has gone south and allowing the coolant to escape under pressure while driving.

 

[blcknspo0ln]

you sure? I have had both 7 bolts as my turbo DSMs and both used ARP's in which I have torqued in that same sequence. To specify, exactly, I believe suggested torque spec was 85 ft/lbs. Either way, I'm sure ARP has it posted somewhere on their site (or even on thi site).

 

[92awddsm]

you sure? I have had both 7 bolts as my turbo DSMs and both used ARP's in which I have torqued in that same sequence. To specify, exactly, I believe suggested torque spec was 85 ft/lbs. Either way, I'm sure ARP has it posted somewhere on their site (or even on thi site).

6 bolt specs.

I cant find the specs on a 7 bolt head stud at the moment but it is smaller and requires less torque than the 6 bolt. The set I installed a few months ago I believe called for somewhere around 75ft/lbs. That might have been with moly lube and maybe 90 with 30wt oil but 90 with moly lube and 110 with oil is way too much for the 11mm studs to handle. I know someone that tried 115 ft/lbs of torque with their 7 bolt studs using oil and he had to remove the head to get the broken stud out of the block.

 

[bird man]

the responses i hae got were pretty much the same thoughts i had myself. i have tried everything with the exception of re torquing the head bolts and pulling off the turbo to check it.

i have:
replaced the radiator cap ( twice )
replaced the thermostat ( twice )
replaced the radiator
replaced the hoses
made sure to burp the system every time i add coolent.
I have dsmlink and have the fans set to high constantly

ill keep everyone posted after i look at the studs and if anyone has some ARP studs they wanna sell for a 7 bolt please let me know tonight if possible and ill just wait to mess with it til i get them from you.

if anyone else has any ideas please let me know.

 

[olmytsi]

Do yourself a favor and pick up a haynes manual from autozone or pepboys. It has the sequence in it. I have no idea what you are supposed to torque the stock head bolts to but i have a 6 bolt swap with arp head studs which i torqued to 90.

 

[silver bullit]

What is the condition of your radiator and hoses?

 

[bird man]

What is the condition of your radiator and hoses?

BRAND NEW

 

[jumpfroggy]

Boiling coolant is usually either bad coolant pressure (rad cap, which you checked), or headgasket. The first thing you should do (except for possibly the rad cap) is compression check the cylinders! This will tell you right away if the headgasket is going. If you don't want to compression check right away, take a look at the coolant and oil for the typical signs. Since your coolant is boiling away, you prob wont be able to see the state of it in the engine.

Look at your oil. Does it look normal (either clear/yellow, or dark brown). If it's a chocolate-milk color, kinda thick looking, then you got coolant in the oil = headgasket leak. Fill up the coolant and do another coolant "burp". Bubbles will come out, but if you look close they may have small wisps of smoke... that's exhaust bubbles, not normal air bubbles. Also, smell the bubbles and they shouldn't smell like exhaust/fuel. Burping should quit after a while if it's just air, but if it's exhaust then it'll just keep on burping. If you let the car sit, and then start it up and it's rough and smokes for just a little while = headgasket (coolant leaks into cylinders while car is idle since there's less cylinder pressure, I think). Goes away with a few revs.

Compression check! Do it! I'm curious, since I had this happen once. My only advice (besides doing the correct tests) is not to drive it till you fix it. If it's your daily driver (like mine was) it's tempting to think you can just keep filling it up. But if you overheat your head it'll warp (and it sounds ilke you're letting it overheat a lot), then you've got headgasket AND warped head to worry about. Turns a simpler repair into a more expensive and complicated one. Take the bus if you have to... I wish I had.