Hi!

So I just finished up my build, and car drove perfectly couple of miles, but suddenly, after a trackday, I got some overheating issue along with ALOT of coolant missing.

Spec:
EK4
B18c block sleeved by benson
Cp pistion, pauter X rods, LS crank, acl bearing, assembled by laskey racing.
B18c6 head, with all ferrea valvetrain, portet, prepped and mount by shop in Norway
Full-race turbo kit with gtx3076 gen 2
mishimoto full size x-line radiator
setrab 60 row oil cooler

So there is a lot of symptomes, so please bear with me, and with my some bad language.

- After the car started overheating and boil(mainly because my fans did not come on) I had a hard time get it air free when i bleed it. There was some bubbles from the radiator after I had bleed throug almost 4 liter of coolant(Water expands, goes out the radiator top, cools down, refill, like that bleed method). So I eventually got tired, so just tried to drive, but car overheatet after a couple of laps.
- The problem is that the overflow tanks gets full and it boils over from there in to the engine bay, mainly when I drive hard.

- When I'm crusing, the temp gets up to normal, water expands, fill up the overflow tank as it should. But when the car cools down, the water from the overflow tank doesn't flow back to the radiator. I tried to change to new mishimoto radiator cap which didn't solve m problem. This happend when I bleed the system, and everything works fine for a couple of hours.
- There is no sign of white smoke from the exhaust, and there is no sign of water in the oil, and oil in the coolant system.
- I pressureized the system through the radiator cap and found two water leaks. I have fixed them. But I still have my problem.

The weird about the whole thing is these symptomes:
- In the morning when I start the car and start driving, the oem temperature sensor reads around 125 degree celcius for a minute, and falls back to normal operating temperature, as if the thermostate doesn't open at correct temperature. But I have also changed this with zero improvements.
- Sometime when it start overheating like that, I can just depress my cluthc and rev the engine to 6k rpm up and down 3 times, and the temperatur will start falling and stabilize.
- When I bleed the system, the car will run great for a about 2 hour, and then starts overheat again.
- It also feels like the overflow thanks gets filled up when I'm on boost and rev it past 9000rpm.

I'm of course leaning towards head gasket, but the fact that there is no coolant in the oil and the other way, no white smoke and compression is 200psi on all 4 cylinders make me think it isnt the problem. Is there any other methode to check if that is the problem?

Any other suggestions?

 

Depending on the failure point if the gasket you won't always have oil and water mixing.

best bet is leakdown test if it pushes air into radiator you have a failed head gasket.

if you don't have a leakdown tester you can use a compression tester just remove Schrader valve and hookup to a compressor I would push about 90psi of compressed air and see what happens

 

 

For my own benefit - You're talking about pushing compressed air into the bottom of the radiator to look for pressure leaks?

Not familiar with this method but sounds like it could work well.

 

it can boil over without the themrostat opening when you are bleeding it. thermostat has to open to bleed properly

 

I dont think your quite following......Im talking about putting pressurized air into the cylinder itself, to see if the pressure escapes past the headgasket into the radiator

end result would be bubbles in the radiator, which would be bad

 

 

Make sure head/block surfaces haven't been warped from overheating.

And thanks 2K, I wasn't really following what you were saying there.