Thread: Hunt the Oil Leak(s)

Have you removed the EGR cooler .. did you have one?

I think brother's has a leak up front there somewhere impossible to locate too.
I'm not getting a lot of time with his car lately tho to trace where it's coming from.

Usually the best path going forward is a really really really good clean up. Waste tons of degreaser on it, pressure wash every nook and cranny and watch like a hawk every few hours.
The trick is to find it before it spreads.

I had to do that on my Tdi a while back, and I had three small leaks creating one large looking leak.
Completely unrelated to a Td5, but mine were: brake vac pump welsh plug(sealed with silicon), cyclone hoses(replaced) and last one I haven't yet sorted .. oil filter area.
With the engine pressure washed, I then sealed up the welsh plug on the vac pump, and 90% of the leak ceased.
The the annoying weep was sorted when I replaced the hoses for the tdi's oil catch cyclone system.
Now the oil filter loses a very small amount, and this oil gets trapped on top of the diff and pools. On a long-ish drive, the pooled oil then gets flung out underneath and looks far worse than it is. On shorter drives(eg. to work) it stays put.

Clean up the area and put some UV detection dye in the oil (maybe you can find something similar locally) Fluorescent Oil Leak Detection Test UV Dye For Car A/C Pipeline Fuel Coolant 744478298117 | eBay then take it to a ride and use a torch... you'll clearely see then

Yes the EGR has been deleted, the degrease is a good idea, so is the flouro oil dye.

Also have a good look at the cam plug always a suspect for leaking

plug.png

Originally Posted by AK83

Now the oil filter loses a very small amount, and this oil gets trapped on top of the diff and pools.

Just dealt with a similar issue on the Tdi300 D1, thinking it was somehow the screw on filter.

Found the problem was a failed o-ring that seals the nearby wax thermostat housing and cap - like the radiator thermostat, it controls flow.

If you are tempted to get an o-ring from the grab pack make sure it is very thin - when bolting up it is easy to break the bolt flanges (rabbit ears) off the cast aluminium cap if the o-ring is too thick - replacement caps are available from MRAutos - don't ask me how I know...

Not sure if the D2 has something similar.

Originally Posted by workingonit

....

Found the problem was a failed o-ring that seals the nearby wax thermostat housing and cap - like the radiator thermostat, it controls flow.

....

Yeah, after much cleaning, running, cleaning etc. I initially thought the o rings on the hoses too .. so I got new hoses, thinking it may also have been the hose crimp connectors.
But after the cleaning/run/cleaning test, I noticed that the hoses themselves were clean, where the filter had a drip of oil on it.
Will inspect the thermostat area more closely next time now, and having just looked at the exploded view in RAVE .. I reckon my issue may be what you just did ..

Cheers for the heads up.

Some oil filter brands refuse to seal properly.. and can fail due to poor thread and seal design failing under pressure. Mine dripped and dripped then failed ..Twice over ie the original and the store replacement.

lots of fluid up front,, sure its oil?