TheSamba.com :: View topic

Sat Jul 12, 2025 10:18 pm

While replacing my water pump, I replaced the oil cooler coolant hoses and put a new oil cooler on. Once i had everything buttoned back up, I refilled with oil and started the engine. Immediately large amounts of oil started pumping out from around the oil cooler. Clearly, I installed something incorrectly but am trying to figure out what?

As part of the refresh I also installed a new oil filter pipe (the threads on my old one were not great). I double nutted the pipe to install it and screwed it in pretty far, however I never felt it bottom out. Is there a point where the pipe bottoms out? And if I did not screw it in to that bottoming out point would that cause a major leak?

The only other thing I can think is that the seal somehow slipped. Or perhaps the new hoses are putting enough tension on the oil cooler that it never seated correctly, although that seems like it would have sorted itself out when torquing down the oil cooler.

Sat Jul 12, 2025 11:42 pm

The pipe depth doesn't matter much, as long as it's tight and you have enough threads left for the cooler and filter.

The o'rings are often shitty, and you need the version with the ears to help.

See the gap here, rather crappy...

Sun Jul 13, 2025 7:11 am

I’m curious about an actual torque for seating the pipe/nipple…nothing in Bentley? I don’t recall…mine’s out in the garage (& I’m not yet) but I may check on that later.

I also had a bad leak at first after doing this job. IIRC, torque spec for the 27mm nut was 18ft/lb, which I used. It was recommended by a real guru to nearly double that to 30. So…I went back in, snugged to 30 & the leak stopped…easy peasy. That was probably at least 10 years ago, been clean & dry ever since.

Yeah, the o-ring has to seat properly to do its job. The tabs on the pins help, but I know I also used a bit of Hylomar or similar gasket sealer as insurance. Never hurts, but just a little smear on all surfaces of the o-ring, you don’t want to gob it all over & risk blocking the orifice of the oil cooler.

- Dave

Sun Jul 13, 2025 6:40 pm

The O-ring is special, do not run a Plain Jane o-ring without the ears or it will fail on the first really cold winter's day even if you can make it seal originally. When tightening the nut you should be able to feel the point when the oil cooler is pulled tight again it's mounting flange, a little more torque beyond that point is what you need. I would think 30 ft*lbs would be fine but have never put a torque wrench on this nut TTBOMK.

FWIW, having owned Vanagons since they were new, I removed the troublesome oil cooler and run without it. No hoses to leak, nuts to come loose, or o-rings to get brittle and let go in the snow, and no chance at all of an internal leak through the cooler. The 1.9 ran fine without the cooler while I had multiple cooler related failures before I round canned the cooler.

Sun Jul 13, 2025 7:33 pm

you stated...

"perhaps the new hoses are putting enough tension on the oil cooler that it never seated correctly, although that seems like it would have sorted itself out when torquing down the oil cooler."

For assembly, install the cooler BEFORE hooking the hoses to the pipes. If you are fighting the hoses while installing the cooler, that MAY cause the cooler to not start off nice and square to the mating surface, and MAY cause the seal ring to slip.
I install the cooler before hooking up the hoses to their tubes, that way the hose are not tugging on the cooler as it is being installed,

.Sounds like you aint sure of where the leak is from , the cooler or the filler, if so, you NEED to ascertain where the leak is co ing from before any repair can commence

Clean up the mess, then shove some paper towels around the two leak sources, even attaching with wraps of tape, then restart the motor briefly while parked and see which towel gets soaked in oil. If you drive during this test, wind from vehicle movement may spread the oil, making leak location difficult to pinpoint.

Good luck.

Mon Jul 14, 2025 11:11 am

Similar to what dhaavers shared, I went back and properly torqued the oil cooler nut and that seems to have done the trick, at least it stopped leaking. i'll be keeping an eye on it obviously. I recently installed an oil pressure gauge as well which is helpful.

For the record, I used the appropriate seal with the 'ears' (purchased through a reputable source) and I applied some hylomar to the seal as well. My initial attempt at tightening was by feel to what I thought was goodntight. once I got the torque wrench it was clear there was still a lot of room to go. lesson learned.