New Radiator Won't Seal...?!?

[Aaron Bakos]

95' 525i 5spd

I noticed I had a coolant leak on my radiator where the upper neck used to be, so I picked up a replacement (Nissen) from Bimmerzone.

Took me less than an hour to change, but when I was warming up the car to pressure check the whole thing, I saw some anti-freeze running down around the overflow tank on the side of the radiator.

I determined that the bleeder screw was not making contact with the little brass nipple down in the hole to seal the system. Two things were going on, the Nissen bleeder screw is shorter than the OEM- and there was some plastic flash or some crap around the brass nipple so the bleeder screw can't make contact with the brass nipple.

If it's not supposed to seal there, ie if the system is supposed to seal when the bleeder screw head seats to the threaded tube, then there is still a problem- I wiped it off a bit and blew on the hole and the air escapes around the hole under the top plastic piece. I expected that just for safety reasons if nothing else.

I'm a bit perturbed...I tried to clear out the plastic with a small blade, but no dice. I have to call BimmerZone tomorrow and see what we can do. I may make a small rubber stopper to stick in there and block things off so the car isn't dead.

I have pics of what I'm talking about if somebody can host for me...e-mail me an e-mail addy to aaronbakos@hot*NOSPAM*mail.com - remove the *NOSPAM*

[Gary M]

Maybe you need a rubber o-ring on the bleeder screw. I don't remember if I had one on my original radiator, but the new name brand one I've got in my car now has one.


95' 525i 5spd

I noticed I had a coolant leak on my radiator where the upper neck used to be, so I picked up a replacement (Nissen) from Bimmerzone.

Took me less than an hour to change, but when I was warming up the car to pressure check the whole thing, I saw some anti-freeze running down around the overflow tank on the side of the radiator.

I determined that the bleeder screw was not making contact with the little brass nipple down in the hole to seal the system. Two things were going on, the Nissen bleeder screw is shorter than the OEM- and there was some plastic flash or some crap around the brass nipple so the bleeder screw can't make contact with the brass nipple.

If it's not supposed to seal there, ie if the system is supposed to seal when the bleeder screw head seats to the threaded tube, then there is still a problem- I wiped it off a bit and blew on the hole and the air escapes around the hole under the top plastic piece. I expected that just for safety reasons if nothing else.

I'm a bit perturbed...I tried to clear out the plastic with a small blade, but no dice. I have to call BimmerZone tomorrow and see what we can do. I may make a small rubber stopper to stick in there and block things off so the car isn't dead.

I have pics of what I'm talking about if somebody can host for me...e-mail me an e-mail addy to aaronbakos@hot*NOSPAM*mail.com - remove the *NOSPAM*

[Aaron Bakos]

Maybe you need a rubber o-ring on the bleeder screw. I don't remember if I had one on my original radiator, but the new name brand one I've got in my car now has one.

There is an O-ring around the screw, but I don't think that's the problem.

It doesn't matter how hard I crank down on the bleeder screw, it won't seal.

[Gary M]

The o-ring on my new non-name brand radiator was deformed and it was also leaking. You might try swapping it out to see if that works.


There is an O-ring around the screw, but I don't think that's the problem.

It doesn't matter how hard I crank down on the bleeder screw, it won't seal.

[Aaron Bakos]

The O-ring is fine. It's not leaking out around the screw...it's underneath the top of the radiator.

I got a small rubber stopper and put under the screw today, and the screw still bottomed out. I don't know what the hell is going on, I just know that BimmerZone hasn't e-mailed me back yet and I need a functional radiator.

My patience is wearing thin.

[Aaron Bakos]

New one in the mail...thanks BimmerZone!

New one will be here Monday-ish...kudos to BZ for getting back to me ASAP.