coolant won't get sucked back in
Thread Starter
Burning Brakes
Joined: Aug 2001
Posts: 1,238
Likes: 0
From: walled lake MI
coolant won't get sucked back in
noticed my coolant will blow out to the overflow as advertised when things heat up, but apparently it doesn't get sucked back in when it cools back down. every time i check the coolant level it is about an inch or so below the base of the filler neck. if i keep topping it off, that amount just gets crapped out back into the overflow.
i am not losing any coolant due to any leaks, since the amount in the pressurized system + overflow seems to stay constant.
i just changed the cap (16 lbs) about two months ago hoping it would solve the problem. no luck.
any ideas would be appreciated.
i am not losing any coolant due to any leaks, since the amount in the pressurized system + overflow seems to stay constant.
i just changed the cap (16 lbs) about two months ago hoping it would solve the problem. no luck.
any ideas would be appreciated.
Melting Slicks
Joined: Nov 2003
Posts: 3,375
Likes: 1
From: Northern CA
Originally Posted by tempest
noticed my coolant will blow out to the overflow as advertised when things heat up, but apparently it doesn't get sucked back in when it cools back down. every time i check the coolant level it is about an inch or so below the base of the filler neck. if i keep topping it off, that amount just gets crapped out back into the overflow.
i am not losing any coolant due to any leaks, since the amount in the pressurized system + overflow seems to stay constant.
i just changed the cap (16 lbs) about two months ago hoping it would solve the problem. no luck.
any ideas would be appreciated.
i am not losing any coolant due to any leaks, since the amount in the pressurized system + overflow seems to stay constant.
i just changed the cap (16 lbs) about two months ago hoping it would solve the problem. no luck.
any ideas would be appreciated.
I just went through that on my 96. The problem ended up being a bad solder joint on the brass tube for the overflow hose right under the radiator cap.
Check for leaks at that fitting and the hose that goes to the overflow tank. Also be sure everything is tight. A small leak that won't spill much coolant is enough to lose the vacuum that is supposed to suck the coolant back into the pressurized fill tank.
I found the leak at the brass tube when I removed the hose to trouble shoot the problem. The brass tube practically fell out of the tank. It has a bad solder joint with almost no solder on one side. It had probably sat ther for 8 years working OK, then finally started leaking enough to lose the vacuum.
If you need a tank, gmpartsdirect.com has them for about $30 plus shipping. About $60 at the dealer and there is no aftermarket souce. I'm just glad you can still get them.
