[datbanana]

I have a 2008 328i SULEV manual that had a power-steering leak coming from where the return hose connects to the loop (#7 and #15 on the picture). I had replaced the hose as I thought that was the problem but it started leaking from the same place again, just a few weeks after I fixed it. I'm wondering whether I need to replace the loop or the hose again?

The leak is coming from the quick disconnect right where part #7 attaches to part #15 on picture below.

[jacraest]

Sounds like it's part #15 if it's leaking again after replacing part #7. I haven't seen this in particular, but if those are crimp fittings, I've fixed it myself before on E36's power steering systems.

Buy some NAPA transmission oil cooler hose. Highest PSI you can get. Use 2 hose clamps on the end, with the screws on opposite sides. (screw point is a deadpoint for pressure), do the same for the banjo fitting. If that doesn't work, then it's probably part #15.

[Tambohamilton]

Originally Posted by jacraest

Buy some NAPA transmission oil cooler hose. Highest PSI you can get. Use 2 hose clamps on the end, with the screws on opposite sides. (screw point is a deadpoint for pressure), do the same for the banjo fitting. If that doesn't work, then it's probably part #15.

Don't do this. ^

It does sound like 15 may be the culprit. You need to disconnect the coupling and inspect the spigot on 15 for any signs of damage. If it's in good condition, you may have got unlucky and pinched the o-ring in 7. I would be surprised if this can't be replaced separately, though BMW don't list it as a separate part.

That hose is on the low pressure side of the circuit, so it's not under extreme pressure like the hose from the pump to the rack.

[datbanana]

Originally Posted by Tambohamilton

Don't do this. ^

It does sound like 15 may be the culprit. You need to disconnect the coupling and inspect the spigot on 15 for any signs of damage. If it's in good condition, you may have got unlucky and pinched the o-ring in 7. I would be surprised if this can't be replaced separately, though BMW don't list it as a separate part.

That hose is on the low pressure side of the circuit, so it's not under extreme pressure like the hose from the pump to the rack.

I'm not sure what to see for damage other than obvious stuff like bending. But from I can see it seems to be completely fine. I was thinking of slapping some electrical tape on the end to see if that could press against the O-ring a bit more to stop it. I just don't want to spend $90 for the loop only for it to still leak. Here are a couple pictures of the spigot and connector, and I took some more here: https://drive.google.com/drive/folde...Ga?usp=sharing .

[Tambohamilton]

I don't think tape will help, but who knows. Are you sure the connector was fully seated?

[adambr]

Anyone know what the size of the O-Rings are for that quick connector? I used a pick tool to pull one out, and with my digital calipers it appears to be 14mm ID x 19mm OD x 2.75mm width x 2.5mm thick (14+2.5+2.5=19) - yes it does feel and look a hair wider than thick.

Wondering if doing a 13.5mm x 19.5mm x 3mm, or 14x20x3 might make it more snug. From what I can tell the metal tubes from the cooler are ~14.2mm

Either that or is there a way to replace the quick connect with a good old fashioned hose clamp? The quick connect fitting is metal and there isn't much play to work with on that hose - the other end that connects to the PS housing is a banjo bolt that's working fine, so I don't want to mess with that.
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Edit - pulled the PS cooler, looks like the upper return tube to the reservoir is closer to 14.5mm while the lower tube (the one that leaks) is 14.25mm. Me thinks its a manufacturing defect with the original OEM part. Debating on ordering a new one, or trying different o-rings (concerned a 3mm might not fit).

[Tambohamilton]

Go with o-rings first. That discrepancy in diameter doesn't sound ideal, but a suitably sized o-ring should sort it fine.

I have no idea what the proper size for the o-ring is, but I'll guarantee that it's round section, not 2.5x2.75/oval (it's probably just deformed a bit, which isn't ideal).

I'd buy a selection of sizes that are close, and see which feels like a decent snug fit.

Let us know how it goes

[adambr]

Special ordered 13.5mm ID x3mm (19.5mm OD). In replacing both the orings on the quick connector hose, it was too tight to put on, so I only replaced the back one and I was able to get it on. But the hose leaked as well so it might be too compressed.

Since 14x2.5 is too small and the 13.5x3 is too tight. Anyone know a better solution? I found there seems to be somewhat standard size o-ring 13.94mm x 2.62mm - I suspect that is what the original oring size is.

However at this point, I feel its better to just cut off the quick connect and use a hose clamp. I'm assuming the hose is the right size to slide over the cooler tube - can anyone help me confirm? Also, how to I keep it from slipping off? I don't think there is enough room to have someone add a bubble flare to the cooler line because of the existing quick connect flare about an inch up (Also, I don't have those tools). Is there a little clip I can use to hold on around the hose clamp and the collar from the quick connect flare on the metal tube?

Since I already spent over $120 on the stupid hose, I'm not quite ready to drop another $100 on another cooler. Any help in addressing this PITA problem would be appreciated.

[efodela]

Hi did you manage to get this fixed. I think my cooler loop needs to be replaced as I have changed the pipe too but still leaking.

[datbanana]

Hi, we replaced both the hose and the cooler loop, but I believe the issue was just the cooler loop in my car.