Tech tip, Pre Filter. Somthing to watch for.

[Nig]

Had this ute for a few years now, always had a problen, when i let the fuel guage got under 1/4 level i would run like hairy goat, add fuel and it slowly run better again. I have replaced several fuel sensores on the system to clear this problem to not much gain, feeling frustrated over this problem last effort i chassed this problem to the fuel tank pick up, thought it might be bent or broken, im in the prosses of pulling the long range tank, this Delphi filter is mounted under the tray, see photo, had to remove it to do the tank, looking at it the tank feed line was fitted to the outlet and the outlet to the inlet, i have changed this filter several times over the past, so these lines have been like this from fitment, its always hard to prime, because this filter sits up close under the tray iv never sighted these direction arrows before, anyway switched them over, primmed the system to the point the primer plunger now sits rock hard, has never ever done this before, I ute has HP i didnt think existed and running better than it ever has. This has renewed my liking to my Navara.

 

[Nig]

Oh , after i fixed the problem i did change both Filters cheers ppl.

 

[tweak'e]

photo ??

what navara?
also what filter element? a lot of the common ones don't flow enough for modern diesels.

 

[Nig]

Its a 3 micron , now runs like new, better, has a few more of the common mods tyese yd25 have.

 

[Been a while]

Had this ute for a few years now, always had a problen, when i let the fuel guage got under 1/4 level i would run like hairy goat, add fuel and it slowly run better again. I have replaced several fuel sensores on the system to clear this problem to not much gain, feeling frustrated over this problem last effort i chassed this problem to the fuel tank pick up, thought it might be bent or broken, im in the prosses of pulling the long range tank, this Delphi filter is mounted under the tray, see photo, had to remove it to do the tank, looking at it the tank feed line was fitted to the outlet and the outlet to the inlet, i have changed this filter several times over the past, so these lines have been like this from fitment, its always hard to prime, because this filter sits up close under the tray iv never sighted these direction arrows before, anyway switched them over, primmed the system to the point the primer plunger now sits rock hard, has never ever done this before, I ute has HP i didnt think existed and running better than it ever has. This has renewed my liking to my Navara.

Best thing I ever did was fit a pick up pump AT the tank and pressurise the lines! Bliss on filter change days! Crack your lines "if needed", bleed screws, hit the key and she's primed!

They say to try and keep a 5psi feed to the pump on the zd's!, ESPECIALLY if you're running pre filters like that.. wack a sensor on the line and a gauge on the dash, you'll see when the filter needs changing or the pump fails- make sure you run a by pass on the pump at the tank!

There's a post on here of when I did mine if you need it..

 

[Been a while]

If she's the zd, look into the spill line/return line mod... same post if needed.

 

[Horatius]

Not sure about having such a fine filter in line with the factory one, extra restriction. Should probably be ok if you have lift pump though. The only benefit I can see is that the factory filter might last longer between changes?

Often thought about putting a sediment/water trap in pre filter though, something with a clear bowl and possibly a really coarse filter. In the end it just seemed like more stuff that could go wrong. The best tip I ever got was just to change the regular fuel filter more often.

 

[Been a while]

Not sure about having such a fine filter in line with the factory one, extra restriction. Should probably be ok if you have lift pump though. The only benefit I can see is that the factory filter might last longer between changes?

Often thought about putting a sediment/water trap in pre filter though, something with a clear bowl and possibly a really coarse filter. In the end it just seemed like more stuff that could go wrong. The best tip I ever got was just to change the regular fuel filter more often.

Yeah I put one in for the extra water trap and inspection glass bowl.. I change the Delphi one out between main filter changes..cheaper!

 

[Nig]

Yeah I put one in for the extra water trap and inspection glass bowl.. I change the Delphi one out between main filter changes..cheaper!

I do three Delphi filters to 1 main, the delphi catches the water and crap befor it reaches the main, and its mu6tch easier to MT the delphi . If you ever try bleeding the water from the main. And bleeding is a snack, i put a hose on the main outlet in to a clear container, i pump the air into the tank through breater tube to push the diesel through to get all the air out, hook the line back up and pluger the primer till it is firm, thats easy, i dont want to introduce any more mechanics than it needs.cheers bro.

 

[Been a while]

I do three Delphi filters to 1 main, the delphi catches the water and crap befor it reaches the main, and its mu6tch easier to MT the delphi . If you ever try bleeding the water from the main. And bleeding is a snack, i put a hose on the main outlet in to a clear container, i pump the air into the tank through breater tube to push the diesel through to get all the air out, hook the line back up and pluger the primer till it is firm, thats easy, i dont want to introduce any more mechanics than it needs.cheers bro.

Good point, I wouldn't have fitted one for that reason also, but,,, I just did a $3g pump so anything to make things better eh

So true about the extra concern when introducing something like this..

 

[tweak'e]

Its a 3 micron , now runs like new, better, has a few more of the common mods tyese yd25 have.

thats way to fine.
CAV don't flow enough at the best of times. i would be using something in the 40-100 mic range.
non-common rail filters are typically 40 mic i think (ie early d22's/d21's).
you want it to work as a pre filter not a main filter.
a fine filter just adds a LOT of restriction.
its one of the most common mistakes i see with aftermarket pre filters. factory pre filters are often just a mesh.

i've had it happen myself where someone had fitted a pre filter. the pre filter clogged up and stopped the engine. fortunately it was in the yard and not out in the paddock.

 

[Nig]

Mines common rail seems to work the treat now itsset up propper. Actualy has spun me out the power is gainned, like pulls over the hills 100% better than ever. Hasnt missed a beat, im testing the fix as i have gotten it down to less than 1/4 tank its still holding a firm plunger and not missing a deat,

 

[Alxmcd]

Where'd you get the filter? Is it cheaper than the others?

 

[Nig]

Ebay has them all at a good price bro.

 

[Nig]

If she's the zd, look into the spill line/return line mod... same post if needed.

No need for one it works great now, to bleed i pull the breather from the chassis holder pump air in with my tyre pump, take the feed hose off the rack pump and poke it into a bottle let it flow till all air ie out of both filters and put it back togeather, do this maybe once a year when i change out a filter or both.