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b3 coolant spitting out (not overheating though)

581 Views 5 Replies 5 Participants Last post by  letsrev
Well, like the subject says, I have a 91 passat, 16v, and the durn thing keeps spitting out coolant from the overflow tank. It isn't overheating, it will do it with the engine somewhere in the mid-temp range, (Probably as soon as the thermostat opens).
No it isn't overfilled, because it will spit out even when it's low, and after it spits out I'll wait for it to cool down and settle, then add only to the bottom line on the tank.
So if there isn't too much water in the system, what could cause this? I think if the water pump was bad it would overheat, because the temp sensor is in the block right? Could the radiator be clogged? (I'm going to take off the bottom hose and try to run water through it).
Could the water jackets in the block be clogged? Bad thermostat possibly?
The problem is it's hard to tell which direction the coolant flows because there are so many "y" connections on the system.
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Re: b3 coolant spitting out (letsrev)


1.Fill the water overflow to the top,
2.put your heater on full,
3.no.2 on the fan.
4.leave the cap off your overflow
5.Run engine for 15 min,and watch all the bubbles burst out of the top of the overflow.
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Re: b3 coolant spitting out (letsrev)

I had that problem when i just got my 92 Passat. I took it to my mechanic because i couldn't figure out the problem. He fixed the problem in 30 seconds by replacing the rubber washer in the lid. Try that. Hopefully it'll fix the problem.
Re: b3 coolant spitting out (letsrev)

My car was overheating and the temperature range was fine. The coolant was low in the block, so I was actually just getting a temperature reading on the steam.
Do you have an MFA? If so, how's your oil temperature.
Re: b3 coolant spitting out (letsrev)

Definetely check the O-ring up inside the overflow tank cap, it might juts be ajar that happened the first day I had my 'sat.
Re: b3 coolant spitting out (psd13)

The cap is on fine and the gasket is good, the coolant is coming out of the side of the tank. There are two holes in the side (yes, they're supposed to be there) beneath the little black cover with the picture of the book with an exclamation point on it. Peel it back an you'll see. This is where the system is designed to vent overflow.
I will try the heater idea though, thanks.
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