coolant bubbling

[smithers584]

for about a year now i have had my swap (s13 sr) and everytime i drive and turn my car off, i hear a bubbling/gurgling sound from behind the motor between the firewall. my temp always stays fine and car runs great, anyone elses do this? know what it is? also car vibrates bad at 60-70 mph but if i let off the gas at that speed it completely stops vibrating? still symptoms of a bad carrier bearing?

[Irukandji]

On my dohc ka, the coolant was bubbling because my waterpump had a huge leak, so all the coolant in the radiator was draining while the coolant in the tank stayed in there. Some air bubbles got in the lines and cause little bubbles in the coolant. If you haven't replaced your water pump yet, you might as well do it now since you're going to need to do it down the road. Replace the thermostat while you're at it.

As for your vibration problem, it could be a number of things. I'm not too sure on your problem since you say the vibration stops when you let off the gas. If vibration still persists, try getting an alignment, if that doesn't cure it, check your brake rotors (if they are warped), and finally balance your wheels.

Hope that helps.

[ManoNegra]

Boiling coolant on one of my old cars was caused by an aging radiator cap. Loosing pressure in the system. Got a blitz one and the solved the problem.

[smithers584]

maybe i will get a new cap, i do not any have coolant leaks. it definately is not a wheel, alignment or brakes. im pretty sure its the carrier bearing, just thought i would see if anyone agrees. the weird part is that if i let of the gas at those speeds it stops. its definately drivetrain related. thanks though, any other ideas? flushing the coolant might not be a bad idea either.

[Irukandji]

Try flushing the coolant and buy a z32 radiator cap... same price as 240 but holds more pressure (16lbs vs. 13lbs). You may need to buy a new radiator drain cock as well, because mine snapped the moment i tried to put it back in.

if you think its the drivetrain, why not change the transmission and differential fluid?

[smithers584]

sorry forgot to mention, i did that this weekend, used lucas 80-90 and some lucas oil stabilizer.

[omgosh]

My car does the same thing, Im thinking it might be a tiny crack in the headgasket...

If I idle my car with the cap off, I get lots of bubbles after the thermostat opens. It doesnt stop bubbling after a while like it should from what I hear, and I have something that looks like exhaust gas coming out of the cap.

Weird thing is that the car runs pretty well still. But you might want to check out if it does the same thing as mine with the cap off...good luck!

[smithers584]

im not so worried about the coolant bubbling, but i am concerned about the vibrations, they are getting pretty violent now. i really need some advice because i am about to ship out to Kuwait and i have to leave the car with the wife. i guess ill start by changing the carrier bearing? anyone disagree?