Temporary overheating trouble.. good info

[fujioko]

Today is day two of the BMW resurrection. Anyway on the way to the office I stopped to get some coffee .. I noticed steam coming from the front of the car. A quick check under the hood and I saw that the air bleed screw on the radiator was leaking. I tightened the screw a bit more and the ****er snapped off!

I made it to work without any trouble and did a quick repair during lunch. (semi half ass but functional)

On the way home the temp gage spiked to about ¾… I pulled into a gas station to give a look. The radiator appeared full and the bleed screw was only weeping a tiny amount.

I shut the car down and waited a bit. In a short while the car was cool enough to pull the radiator cap. Once again everything appeared normal. I started the engine and let it run about 30 seconds.. all of a sudden violent bust of coolant erupted from the open cap.

Out of the corner of my eye I saw the lower rad hose wiggle and move a bit (right hose). Then the hose popped back into shape.

Ahhhhh….. the hose had collapsed!

I had thought my hoses were “ok” but I guess I was wrong. I find it odd that the hose would stay collapsed with the engine off and the rad cap off. A mystery of sorts. Nevertheless its time for new hoses.

Thought I would share my odd occurrence. I think I was lucky to see the hose “move”.. otherwise I would be asking questions instead of sharing a story.

[Mr Project]

On my RX-7s the lower radiator hose would often collapse at higher RPMs due to the suction from the water pump. The solution was to install a spring inside the lower hose....if you keep having trouble after a new hose you might try that option as long as you can find one that is a tight fit.

[joshua43214]

What you describe can easily be caused by a faulty radiator cap, or improper bleeding. When you stop at the dealer to get a new bleeder, pick up a new cap at the same time, its cheap insurance and they dont get replaced as often as they should.

[fujioko]

I admit the bleeder screw has been NFG for a while. It always seemed to weep. Anyway A quick trip to the dealer yielded a new screw for only $4.50.

I’m putting together an order for all the hoses, so I’ll throw a cap in for good measure.

The car seems to be running well and maintaining an even heat for the time being.