Elijah
Elijah New Reader
Nov. 19, 2012 6:25 p.m.

hello GRM, I have a 90' 325is. I have had my bimmer for a couple months now, when I first bought it it had a weird problem, it would run hot (creep up to the 3/4) but only when i was idling or running at very low RPMs. i thought it was the fan clutch but after about a week and then it just completely stopped. so i left it alone. but recently i decided to check on the coolant when the engine was completely cool. as i unscrewed the overflow tank cap it slowly hissed for about a minute. now the same problem came back as before... why was there pressure in the cooling system when it was completely cool? did this pressure somehow fix the problem i was having with the idle? ALSO the coolant fan switch wires are messed up and possibly not making any connection. but it was like this the entire time ive had the car.

thanks for your help guys.

mad_machine MegaDork
Nov. 19, 2012 6:51 p.m.

might always be some residual pressure.. and the way a BMW cooling system is set up.. it keeps the coolant out of the reseviour. you most likely have an air pocket now. You will need to open up the bleed screw at the top of the radiator and top it off till coolant comes out.

It will leak some for a while afterwards.. and then calm down

stuart in mn PowerDork
Nov. 19, 2012 7:00 p.m.

Yes, it sounds like air in the system - with the engine off open the screw and add coolant until it runs out the bleeder. Tighten it up, start the car and get it up to operating temperature, then while running crack the bleeder screw again until the coolant coming out is free of air bubbles.

Elijah
Elijah New Reader
Nov. 19, 2012 9:11 p.m.

Thanks guys I'll try bleeding it tomorrow and let you know how it goes

You'll need to log in to post.

Also on Grassroots Motorsports

You Need This: E39-Chassis BMW M5 for $6000?

6 hours ago in News

Buy one of our favorite Q-ships.

Grassroots Motorsports LIVE! on Wednesday, August 23: Building a Homemade Sim Rig

11 hours ago in News

We’re taking our sim-racing game to another level.

That's What i Like: What Attracts Us to Specific Cars?

12 hours ago in Articles

I just spent 10 days in one of my new favorite cars: the 2017 VW GTE.

Your Projects: Wide-Body, V8-Powered Porsche 944

1 day ago in News

Wing, flares, V8 swap and more!

You Need This: Eclipse!

1 day ago in News

Today's special.

Your Projects: Boosted and Flared E30 BMW

1 day ago in News

Another forum member put it best: “This build is absolutely mental. And I mean that in the best possible way.”

You Need This: 1990 Suzuki Carry 4WD Mini-Truck

1 day ago in News

It looks cool, matches our cargo shorts, and makes little sense.

Concours d’Lemons: Showcasing the Best of the Worst and the Worst of the Best

1 day ago in Articles

This year’s Concours d’Lemons celebrated two cars rarely associated with the glitz and glamor of Monterey.

You Need This: Gullwing Doors and Exotic Styling for Just $1500

1 day ago in News

Meet some brown ’70s awesomeness.

Acura Unveils New Prototype Race Car in Monterey

3 days ago in News

Acura yesterday unveiled the new Acura ARX-05 prototype race car.

OUR SPONSORS

Grassroots Motorsports Magazine

Subscribe Today

Also get your instant access to the digital edition of Grassroots Motorsports Magazine!

Learn More
15eyvyviIRxWjVNKaoAsvfMYd2Lpmpy7