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Air getting into cooling system some how...

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I agree Newbie

I agree

Posted
Posted

Hi everyone, I have had trouble with the car since I got it (2002 m35 VQ25DET) it seems to get air into the system somehow after just installing a bleeder as someone previous broke mine and bled it properly finally after replacing thermostat and radiator. On a inclined driveway was bleeding it and seemed fine held temp nicely and drove for 5 minutes floored it once and then finished going around the massive circle, and after flooring it about 3 mins later it starts to go up in temp from dash then aftermarket goes up fast.

Then once it's on and and have returned home I loosen the bleeder and all this hot mist and air comes out was coming out for about 5 minutes, but before hand there was no air in it.

Since I've got it it overheats then pisses out coolant and steam out of overflow even after the replacement s of thermostat and radiator, and then bleeding. 

It's currently on 12 psi. My father says it could be air from the turbo and it's leaking through a gasket into cooling system... But I thought I might ask the experts here.

Please help me 😳

 

maddy400r33 Enthusiast

maddy400r33

Posted
Posted

Not an expert on bleeding air, but I have jacked a car up. Loosened the highest point coolant hose, which was on this model, not a skyline.

The hose that went into heater matrix.

Could actually hear the air escaping, then coolant, tightened up hose! Sorted. 

robbo_rb180 Grand Master

robbo_rb180

Posted
Posted

use a funnel/cut down coke bottle at fill point, car running and also heater on full. will take a while but will bleed up, I have found using one of these the best for actually bleeding cooling systems
image.jpeg.c7fd9ed01051188ac8cf3b6139b1ad06.jpeg
one other thing could be a blown headgasket.........

Kinkstaah Grand Master

Kinkstaah

Posted
Posted

Ye, this is also a symptom of having combustion gases (not turbo boost, but still sorta kinda boost in a way) in your coolant. Typically through a gasket but in my case it was through the block 😮

I recently bought a rad cap funnel kit and oh man they are great. Should have been the first tool I ever bought.

nickcorr Proficient

nickcorr

Posted
Posted

Try the Stagea M35 section mate.

The M35s are a nightmare to bleed. There was even a bleeding kit created by Scotty, that was using an addiitonal bleed point in the valley, as used by the VQ40 in the Pathy.

It does take hours to do it properly.. I know this from when i had the rad in my M35 replaced.

I agree Newbie

I agree

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Posted (edited)
12 hours ago, GTSBoy said:

More likely it wasn't actually bled the first time. You don't want to hear it, but it's almost certainly the case. Got a bleeding funnel for the rad cap?

It wasn't bled when previous owner change the coolant 400 KMs before I bought it, when he took me for a 30 min drive he turned the heater on full ball and it cooled down straight away... But it doesn't work for me at all and between then and now I've replace thermostat and radiator so more air in the system...I am currently doing it again but putting nose down hill not up hill this time. I wish I could have bled it, but had no bleed screw so had to buy one.. no I don't have bleed rad cap.

 

Edited by I agree
GTSBoy Grand Master

GTSBoy

Posted
Posted

There is quite a chance that running it with a large air pocket in it has overheated something and done the HG or cracked something, per what the others have said.

The bleeding funnel I mentioned is not a bleeder on the rad cap. It's a funnel that goes where the rad cap is, to increase the head height of the rad to help get water in and air out. Makes the highest point in the system right up high above the rad cap. Same as the cut coke bottle mentioned above. Needs to seal in the rad cap throat fairly well though, otherwise it won't work.

Ben C34 Grand Master

Ben C34

Posted
Posted
3 hours ago, I agree said:

he turned the heater on full ball and it cooled down straight away.

you telling us it overheated on the test drive, and you with no mechanical knowledge decided to buy it anyway?

 

 

I agree Newbie

I agree

Posted
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Posted
2 hours ago, Ben C34 said:

you telling us it overheated on the test drive, and you with no mechanical knowledge decided to buy it anyway?

 

 

I didn't buy it...I swapped it for my mr2 Spyder that got hit by a truck (hit and run) and had a bent chassis and damage all over the car and day after being hit, was caught in the massive Springfield storm and came through the roof of the cars and hit me in the head and had 2 seizure after that, it was a write off bad had no insurance, we swapped it as he wanted for parts... And was a driving defect after all that.

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