[mweisdorfer]

I have a small leak at the connection of the lower coolant hose, on the coolant expansion tank. I've replaced the O-ring a couple of times w/ out much success. The coolant hose is actually a series of connections that run down to the subframe and over to the heater hose connectors. I really want to avoid $125.00 for a new set of pipes and then having the joy of replacing it...

I think the connector is shot. It's original to the car at 174,000 miles. After replacing the coolant flange to the OFHG a couple of months ago, it gave me the idea of just replacing the connector. The hose is fine.

Anyone ever do this? Where do I get just a connector?

Please Advise....

[feuer]

I might have that whole line. I will check and let you know.

[smass]

It is annoying that that hose does not have an aftermarket alternative. All of the 15 other hoses can be purchased more affordably with quality aftermarket options. You could put some RTV on the o-ring area. Believe it or not, that is one of the easier hoses to replace.

[mweisdorfer]

Originally Posted by smass

It is annoying that that hose does not have an aftermarket alternative. All of the 15 other hoses can be purchased more affordably with quality aftermarket options. You could put some RTV on the o-ring area. Believe it or not, that is one of the easier hoses to replace.

I looked at it. It's attached to the subframe and then it wraps around & goes towards the firewall on the drivers side.

If I could get a used one for $40.00, I'd just take the connector out & replace it!!!

[smass]

Originally Posted by mweisdorfer

I looked at it. It's attached to the subframe and then it wraps around & goes towards the firewall on the drivers side.

If I could get a used one for $40.00, I'd just take the connector out & replace it!!!

There is a junction connector below the air filter box where it continues to the firewall as a heater hose.

[feuer]

Originally Posted by mweisdorfer

I looked at it. It's attached to the subframe and then it wraps around & goes towards the firewall on the drivers side.

If I could get a used one for $40.00, I'd just take the connector out & replace it!!!

Deal. I will send you my info. Or not. Unless you empty your inbox lol

[feuer]

I have the hole line and two other lines with same connector but lines are different. Your choice

[mweisdorfer]

Originally Posted by feuer

I have the hole line and two other lines with same connector but lines are different. Your choice

I'll take the smaller hose, as long as it's the exact same size as the one I need.

I'm not gonna replace an entire hose that length with a used hose. No offense. If I did that, I'd buy it new. I really don't want to replace the hose at all. I just want to replace the connector. If and when the hose goes, that's when I'll replace it with a new one. The radiator hoses on the e90 are pretty stout IMO. I sometimes laugh when I read about guys on this forum wanting to proactively replace the radiator hoses, and they are 125,000 miles in or something 😂 O-rings yes, but that's all you really need to do.

How much do you want for it?

I cleared out my inbox

[feuer]

Originally Posted by mweisdorfer

I'll take the smaller hose, as long as it's the exact same size as the one I need.

I'm not gonna replace an entire hose that length with a used hose. No offense. If I did that, I'd buy it new. I really don't want to replace the hose at all. I just want to replace the connector. If and when the hose goes, that's when I'll replace it with a new one. The radiator hoses on the e90 are pretty stout IMO. I sometimes laugh when I read about guys on this forum wanting to proactively replace the radiator hoses, and they are 125,000 miles in or something 😂 O-rings yes, but that's all you really need to do.

How much do you want for it?

I cleared out my inbox

Is from 2010 with 75k. Is about the same work. You need to be very careful cutting the ring to remove connector. Then you need to use regular screw hose clamp. I will send you PM later.

[Efthreeoh]

Maybe the leak is on the reservoir tank side?

[mweisdorfer]

Originally Posted by Efthreeoh

Maybe the leak is on the reservoir tank side?

I replaced the reservoir tank in August last year. The. Brand I bought from FCP was Behr; I even bought a new cap.

[Efthreeoh]

Originally Posted by mweisdorfer

I replaced the reservoir tank in August last year. The. Brand I bought from FCP was Behr; I even bought a new cap.

Ah, so that explains my conundrum, because I was wondering how the connection was disturbed to cause it to leak. I'm not sure replacing just the connector on the hose with another used connector is going to solve the issue for you. It seems like the design of the cooling system connections on the E90 are one-time-fit connections. When I replaced my cooling system hoses, the temperature sensor that sits in the lower radiator hose (on some models) didn't seat properly when I reinstalled the old sensor. I ended up needing to get a new, fresh sensor to prevent it from leaking.

Why an open hose with hose clamp doesn't work for BMW, I'll never understand. Re-invention of a part to address a problem that was solved 100 years ago, is just a German engineering exercise. As former manufacturing engineer, I just don't see the manufacturing assembly process savings vs. the expense and complexity of manufacturing injection molded critical-dimensioned parts.

Apologies for the rant.

[je335iau]

Had the same issue. Replaced full lower hose in 20 minutes. Not too hard to replace.

[feuer]

Originally Posted by Efthreeoh

Ah, so that explains my conundrum, because I was wondering how the connection was disturbed to cause it to leak. I'm not sure replacing just the connector on the hose with another used connector is going to solve the issue for you. It seems like the design of the cooling system connections on the E90 are one-time-fit connections. When I replaced my cooling system hoses, the temperature sensor that sits in the lower radiator hose (on some models) didn't seat properly when I reinstalled the old sensor. I ended up needing to get a new, fresh sensor to prevent it from leaking.

Why an open hose with hose clamp doesn't work for BMW, I'll never understand. Re-invention of a part to address a problem that was solved 100 years ago, is just a German engineering exercise. As former manufacturing engineer, I just don't see the manufacturing assembly process savings vs. the expense and complexity of manufacturing injection molded critical-dimensioned parts.

Apologies for the rant.

My 2008 335i n54 had 3 coolant pump replacements, 2 radiator replacements and 1 engine swap while still on all original hoses with exception of the top hot coolant hose that developed leak at the mold injection spot. So rest of the hoses have been off and on few times and don’t leak, yet....

[mweisdorfer]

Originally Posted by feuer

My 2008 335i n54 had 3 coolant pump replacements, 2 radiator replacements and 1 engine swap while still on all original hoses with exception of the top hot coolant hose that developed leak at the mold injection spot. So rest of the hoses have been off and on few times and don't leak, yet....

Ya, I always have said the stock coolant hoses are fairly stout.

[Efthreeoh]

Originally Posted by mweisdorfer

Ya, I always have said the stock coolant hoses are fairly stout.

Me too. I posted a DIY in 2014 for replacement of all 9 N52 coolant hoses and said the same thing at the time.

[feuer]

Originally Posted by mweisdorfer

Ya, I always have said the stock coolant hoses are fairly stout.

Originally Posted by Efthreeoh

Me too. I posted a DIY in 2014 for replacement of all 9 N52 coolant hoses and said the same thing at the time.

Aha, thus I cant sell the used hoses I have lol

[kloving]

I know this is late, but want to post this for those with a similar coolant leak involving the heater core supply hose connected to the upper radiator hose. I believe you are addressing a leak at the 45 degree angled quick connector on the heater hose at the upper radiator hose. I cut off the connector and tried to re-use, however, I found that this was futile because the connector does not have a "bulbed" end to securely hold a screw type hose clamp. I purchased a new heater core supply hose (BMW HVAC Heater Hose - Genuine BMW 64216983858 for an E90 335i, a 328i is a different part #) from FCPEuro, $40, and replaced the entire hose, which turned out to be a much easier job than cutting off and attempting to re-use the connector.