GU TD42 twin oil filters.

[Tins]

I'm trying to help my son with his 2003 GU Patrol which did a head gasket. That's fine, but the car is converted from the 3.0l hand grenade to a TD42, probably from a GQ. This engine runs twin oil filters. Fine, not a bad idea. However, when I came to remove the filters ( head gasket, you change this stuff, right? ), the rear filter was empty, and showed no sign of oil ever being in it. The front filter was as you'd expect. Does anybody have Nissan experience and could tell me what's going on?

I don't like mysteries when it comes to engines.

[rick130]

That's really odd, although it may just be the anti drain back valve not holding and the oil has drained back to the sump.
This used to happen all the time to the TD42's and TD42T's I serviced, and pretty common in general for standard nitrile ADBV's to not hold.

There were two versions of the twin filter setup.
One ran two full flow filters, the other ran one full flow and one combination filter, which is part full flow and part bypass (ie. a high efficiency, low micron element) in the one can.
The fitting for that one is a different size and style to the full flow filter fitting.

[Tins]

That's really odd, although it may just be the anti drain back valve not holding and the oil has drained back to the sump.
This used to happen all the time to the TD42's and TD42T's I serviced, and pretty common in general for standard nitrile ADBV's to not hold.

There were two versions of the twin filter setup.
One ran two full flow filters, the other ran one full flow and one combination filter, which is part full flow and part bypass (ie. a high efficiency, low micron element) in the one can.
The fitting for that one is a different size and style to the full flow filter fitting.


Thanks. Both filters are Z115s. The strange thing to me is that the rear filter seems to have never seen oil, although I haven't actually dissected it.

[jbe]

I had a GQ TD42 for twelve years and on every oil change both identical filters were full of oil.

[Tins]

I had a GQ TD42 for twelve years and on every oil change both identical filters were full of oil.

Which is what I'd expect.., and why I asked. I was perplexed.

Perhaps there's a blockage somewhere. OP seems fine, but I don't know what they usually run. Maybe I should remove the filter housing.

[rick130]

The Donaldson I mostly used wouldn't hold, it'd always drain back past the ADBV and so the filter had nothing in it when spun off.
Genuine would hold fine.

[Tins]

The Donaldson I mostly used wouldn't hold, it'd always drain back past the ADBV and so the filter had nothing in it when spun off.
Genuine would hold fine.

Hmm. The ones fitted were Ryco. So are the new ones. I'll run it and then see.

[rick130]

John, from memory the filter pressure relief/bypass valve was in the aluminium housing they screw onto, not the filter, so check to see if that's not stuck open.

[Tins]

John, from memory the filter pressure relief/bypass valve was in the aluminium housing they screw onto, not the filter, so check to see if that's not stuck open.

Thanks Rick. Does that mean that the PRV is in the housing as well? I’m asking only for the info.

[Tins]

Thanks Rick. Does that mean that the PRV is in the housing as well? I’m asking only for the info.

Whoops, reading this on my phone. Not used to that.

[jbe]

Did you try to post this issue on the Patrol4x4 forum? I haven't been on there for years but there used to be very knowledgeable and helpful people on there.

[Tins]

Did you try to post this issue on the Patrol4x4 forum? I haven't been on there for years but there used to be very knowledgeable and helpful people on there.

My son did I believe. I'll be seeing him and the car on Saturday. He said something about the bleed back line pressurising. I'll go on there myself, as my son is a fitter and doesn't speak the language[bigwhistle]

Thanks for the suggestion.