[iqraceworks]

The top hose going to the trans cooler on my 07' 335i is starting to drip some coolant. I got on realoem.com but they don't show what size internal o-ring is used in the hose connection. Does anyone know what size o-ring I need as a replacement?


It's hose #9 at this link


https://www.realoem.com/bmw/enUS/sho...diagId=17_0319

[mweisdorfer]

Originally Posted by iqraceworks

The top hose going to the trans cooler on my 07' 335i is starting to drip some coolant. I got on realoem.com but they don't show what size internal o-ring is used in the hose connection. Does anyone know what size o-ring I need as a replacement?


It's hose #9 at this link


https://www.realoem.com/bmw/enUS/sho...diagId=17_0319

Is it dripping when it's unattached to the fan & you are working on the car? That's sort of normal. Mine doesn't leak when it's attached to the fan. It will leak some when I'm moving it around or bump it when under the car.

There are o-ring e90 kits you can buy

[iqraceworks]

It wasn't leaking before....but after pulling the electric fan out and moving the cooler around, the fitting has started to drip. Depending on how I move the fitting around, I can get it to drip pretty good.

I guess I can put the fan back in and bolt the cooler back up to the fan and see if that gets it to stop leaking.....seems kind of strange that it's that sensitive though....... that's normal??

[mweisdorfer]

Originally Posted by iqraceworks

It wasn't leaking before....but after pulling the electric fan out and moving the cooler around, the fitting has started to drip. Depending on how I move the fitting around, I can get it to drip pretty good.

I guess I can put the fan back in and bolt the cooler back up to the fan and see if that gets it to stop leaking.....seems kind of strange that it's that sensitive though....... that's normal??

I've always experienced that even with a new O-ring in the connection

[Jeef]

get a new line, it shouldn't leak.

[mweisdorfer]

Originally Posted by Jeef

get a new line, it shouldn't leak.

That particular line is part of a bigger line & it isn't cheap

[IllSic_Design]

Originally Posted by iqraceworks

It wasn't leaking before....but after pulling the electric fan out and moving the cooler around, the fitting has started to drip. Depending on how I move the fitting around, I can get it to drip pretty good.

I guess I can put the fan back in and bolt the cooler back up to the fan and see if that gets it to stop leaking.....seems kind of strange that it's that sensitive though....... that's normal??

I actually always have this problem when removing the fan and/or moving the cooler around. It is always fine once bolted back up properly though lol. Going to get rid of it altogether soon enough when I put a manual radiator in and switch to a different oil cooler(BMS) setup for the trans

[iqraceworks]

Well.....once I got the cooler bolted back to the fan, and everything back in its place....no leaks. I drove the car around and let it get up to temp....still no leaks.

I'm assuming it was leaking just from moving the fitting around when I to the fan out. So far so good!

[streetpro]

it will leak, sooner or later, especially when in hot&slow urban driving you floor it...

[feuer]

Originally Posted by iqraceworks

Well.....once I got the cooler bolted back to the fan, and everything back in its place....no leaks. I drove the car around and let it get up to temp....still no leaks.

I'm assuming it was leaking just from moving the fitting around when I to the fan out. So far so good!

Yes, they leak when you move them but as above poster said it will leak eventually even when you are not moving it, but not especially when urban driving but probably when temperatures drop.

[Bimmer_Engineer]

Originally Posted by feuer

Yes, they leak when you move them but as above poster said it will leak eventually even when you are not moving it, but not especially when urban driving but probably when temperatures drop.

I had the same issue...I just decided to replace the hose and the fitting so I didn't have to worry about it springing a leak at an inopportune time...

[iqraceworks]

I was up under the yesterday messing with my new inlets I'm installing...and so far, not a single drip from the fitting. Might buy a new hose to have on hand in case it ever starts leaking on me.