Oil cooler seals leaking? Pictures inside.

TDI Convert · Mar 5, 2013

From the top:

From the bottom:

It looks like the oil is leaking from above the oil cooler to me. Can oil migrate upward like the pictures show? Or is something else leaking?

Mr. Flibble · Mar 5, 2013

I have never heard of oil migrating upwards - except when a high pressure leak occurs, pushing the oil violently upwards. I had this happen on my van when my oil filter was attached incorrectly, spraying oil upwards from the bottom of the engine.

In this photo, it sure looks to me like the oil is leaking down.

TDI Convert · Mar 8, 2013

Mr. Flibble said:
I have never heard of oil migrating upwards - except when a high pressure leak occurs, pushing the oil violently upwards. I had this happen on my van when my oil filter was attached incorrectly, spraying oil upwards from the bottom of the engine.

In this photo, it sure looks to me like the oil is leaking down.

Thanks for your reply. Any idea what would be leaking above? Oil filter housing?

deadend9009 · Mar 8, 2013

I'd just fix the cooler leak, could be the oil simply moving up by capillary action. Check that first. Its a 2$ gasket anyways...

d2305 · Mar 8, 2013

Check the o-ring on the filter cap. Make sure you don't have two on.

ctags87 · Oct 21, 2013

What was your issue, did it end up just needing new oil cooler o rings/seals or was it something else , just curious because mine is leaking again, changed out the oil cooler seals about this time last year and now they are leaking again and it apears like it's coming from above the cooler like yours ,, let me know thanks

Robert Beecher · Oct 21, 2013

Could be two oil filter orings after one got stuck and stayed on the housing during a filter change. Also dont know about your engine but on mine the crankcase breather pipe attatches to the block down there beside it, it could be broken.

Powder Hound · Oct 21, 2013

New o-rings on the cooler are required. Oil can migrate upwards as oil acts like a super fluid. However, it will not collect like this. Upward migration presents as a very thin coating and proceeds slowly.

You are on the right track in replacing the two o-rings on the top and bottom of the oil cooler.

ctags87 · Oct 21, 2013

ok i have a 99.5 jetta tdi , i understand that part, but i replaced both seals just under a year ago, purchased from idpart.com, what are the odds that the top seal would go bad again in such a short time? btw when i installed them, i didnt lube up the top seal just the bottom because that one spins as you tighten it and the top just gets squeezed up, could that be my problem , should i have rubbed a little bit of oil on both seals before installing? or could i have over tightened it?

btw just wondering before i replace just the seals, at what mileage should the oil cooler be replaced completely, as preventative matenience?

JB05 · Oct 21, 2013

I looked for a how-to at the top of this 101 section, but could not find any. The link for the Huge Vortex how-to's does not open. Anyone know why?

Lensdude_com · Oct 21, 2013

ctags87 said:
ok i have a 99.5 jetta tdi , i understand that part, but i replaced both seals just under a year ago, purchased from idpart.com, what are the odds that the top seal would go bad again in such a short time? btw when i installed them, i didnt lube up the top seal just the bottom because that one spins as you tighten it and the top just gets squeezed up, could that be my problem , should i have rubbed a little bit of oil on both seals before installing? or could i have over tightened it?

btw just wondering before i replace just the seals, at what mileage should the oil cooler be replaced completely, as preventative matenience?

I would replace the oiler cooler with a larger one and a longer rod/retainer thing. The engine oil gets up to normal temperature faster and your FrostHeater (if installed) would warm more of the oil before starting the engine.

EDIT: here's the thread for that :http://forums.tdiclub.com/showthread.php?t=78993

TDI Convert · Oct 21, 2013

TDI Convert said:
From the top:

From the bottom:

It looks like the oil is leaking from above the oil cooler to me. Can oil migrate upward like the pictures show? Or is something else leaking?

I just tightened up the nut on the bottom of the cooler and it stopped leaking. I never replaced the seals. 6 months after I posted this/tightened it it's not leaking still.

Oil cooler seals leaking? Pictures inside.

TDI Convert

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Mr. Flibble

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TDI Convert

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deadend9009

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d2305

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ctags87

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Robert Beecher

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Powder Hound

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ctags87

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JB05

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TDI Convert

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