ZD30 Lift Pump Mod

Had a few people ask about this mod since i have done it and also why i did it in the first place.
I have added a lift pump (fuel pump) into the line of my ZD30, therefor keeping a constant supply of fuel pressure too the injector pump. This helps the strain on the injector pump by not having too suck fuel from the fuel tank, as well as helping with fuel injection timing in the lows revs because of the fuel on demand.
Taking the strain off the injector pump should also prelong its life hopefully, also pluming the spill line back into the return line sends hot fuel back too the fuel tank and not back into the injectors
Since doing this mod i have found i can now pull away from round-abouts in 3rd gear (i have a manual) and thats with 33's, whereas before it used too chug.
I have also found it too be alot more responsive in the lower RPM range.

TO DO THIS MOD THE SPILL LINE NEEDS TOO BE ALTERED! More in the writeup.

I Used a Carter 4600HP Fuel pump which is only 6-8psi of MAX pressure
http://i1212.photobucket.com/albums/...ps6ft5mk9y.jpg

I made a bracket for the fuel pump which i mounted on the exhaust hanger bracket behind the rear wheel, i then covered the pump with some rubber just too stop anything hitting it from the tyre
http://i1212.photobucket.com/albums/...psdqn0hrez.jpg
http://i1212.photobucket.com/albums/...pszsfsqtyg.jpg

Once this was done i used some 90 degree fittings for the fuel hose. The factory fuel hose from the tank is accessed under the carpet in the cargo area of a wagon. I dont have a photo but its a big metal plate, 4 bolts holding the cover plate down about 30cm inwards of the very back. If you have drawers in the back of your patrol then they will have too come out unfortunately. I removed the factory hose from the tank too the metal line and re-routed it though the pump. This is a good excuse to replace all the factory old fuel hoses.

http://i1212.photobucket.com/albums/...ps4nqb73xs.jpg

As you can see in this photo there is a little fuel hose coming out under the intake manifold and joins into the large fuel line from the fuel filter at the pump. THIS IS THE SPILL LINE, the return line from the injectors. As you can see in the photo this needs too be blocked and that little fuel line plumbed back into the main fuel return line from the injector pump otherwise the return line from the injectors will be pressurised and this may damage something. I just used a t-piece for this from enzed.

The fuel pump is just wired from ignition so pump will work all the time. Hope this helps some of you

Awesome write up and mod mate. The bloke at JPC mentioned this to me when he was tuning and chipping my car. But wasn't sure whether it was worthwhile on a CRD, he was gonna get back to me on it, but I completely forgot about it.
I will now look into it!

Sounds worthwhile if running extra filters. I took my pre-filter out because there was too much restriction in the system and I feared damaging the pump rather than prolonging its life. This mod would pressurise the system so that there would be less restriction on the pump.

Thanks Fletcha. Once I sort this electrical mess on mine, this is next.

I run mine with pump inside the engine bay, Walbro FRB13 (8 psi max but will possibly change the pump to 12 psi max output monster), works like charm.
http://www.patrol4x4.com/forum/attac...o_fit_p4x4-jpg

I'll wire overide and inertia switches when I could be bothered with it.
I too gained low down torque a bit, it is very noticeable especially at light throtle it can easily power up where before downshift was required.
It screwed needle/Dawes and JDVM adjustment for limps though because it is able to deliver/advance injection timing better, I still struggle to sort it out

One of the best mods for sure.

Regards

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Originally Posted by Rock Trol

Sounds worthwhile if running extra filters. I took my pre-filter out because there was too much restriction in the system and I feared damaging the pump rather than prolonging its life. This mod would pressurise the system so that there would be less restriction on the pump.

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Good point mate.
This is another reason why I'd like this mod as I run a fuel manager pre-filter too.

Yer I was also looking at running a pre-filter. I definitely think it's a worthwhile mod, I'm trying too get the torque as low in the Rev range as I can and this definitely helped with that

Hey'ya.
What size fuel line did you use? How much line you reckon we need for the job? And what size is the T at the motor?
If I were to do this I just want the shopping list ready so I don't get caught out not having the right parts on hand.

Edit : That T at the motor looks to be two different sizes mate. Adapted down to suit the small return line hose. Do you remember what sizes they are?

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"The fuel pump is just wired from ignition so pump will work all the time."

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I've been looking into this and doing some homework. So when you say it's working "all" the time, I'm assuming this cuts out once it reaches max pressure build-up ? Even if ignition is on, but car not running ?
So in a nutshell, these have a cut-out pressure switch or something built-in ?

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Originally Posted by Hodge

I've been looking into this and doing some homework. So when you say it's working "all" the time, I'm assuming this cuts out once it reaches max pressure build-up ? Even if ignition is on, but car not running ?
So in a nutshell, these have a cut-out pressure switch or something built-in ?

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Good question but I assume if your ignition is on your car will be running so it won't matter. Don't confuse the "ignition on" with "accessories on". So don't wire it into accessories power...

Done the return line mod on mine years ago thanks to you fletch . Worth while for sure.

Quote:

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Originally Posted by Hodge

I've been looking into this and doing some homework. So when you say it's working "all" the time, I'm assuming this cuts out once it reaches max pressure build-up ? Even if ignition is on, but car not running ?
So in a nutshell, these have a cut-out pressure switch or something built-in ?

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All the pumps I have used at work do have a pressure cut out. We use them on small motors mounted on the back of trucks to power auxilary machinery. If you didn't have a cut out in this situation, they could flood the carby which is fairly basic on some of these small motors.

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Originally Posted by mudski

Hey'ya.
What size fuel line did you use? How much line you reckon we need for the job? And what size is the T at the motor?
If I were to do this I just want the shopping list ready so I don't get caught out not having the right parts on hand.

Edit : That T at the motor looks to be two different sizes mate. Adapted down to suit the small return line hose. Do you remember what sizes they are?

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Hey mate the fuel lines are 3/8 I believe for the main tank feed up, I used about 3.5m total for re-routing the lines at the back for the pump and replacing all the lines at the front. The small hose on the t-piece is the spill line and is 3/16 fuel hose. The return hose that the spill line is teed into is 5/16.
The return and spill lines you will probably only need about a foot or so of hose. I just got all my fittings from enzed in town

More questions. Lol. Would 4mm twin core be sufficient for this pump? I can't seem to find any specs for it. Should I run the pump via a relay you reckon too? I might do this anyway actually. Save adding extra strain on the ignition wiring. My wirring is fubar anyway, I don't want to make it worse.

Yer I ran 4mm twin on mine, through a 15amp fuse off the battery and through a relay triggered off ignition. Ign is available off the wiper motor :)

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Originally Posted by big_fletch

Yer I ran 4mm twin on mine, through a 15amp fuse off the battery and through a relay triggered off ignition. Ign is available off the wiper motor :)

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Sweet. I was going to use the Aux battery power as its accessible via the back panel and now theres ign power via the wiper. Cool. Ordered the pump, I will get some fittin's ordered tomorrow when I order my shops stock.

Thanks for posting this DIY big fletch. Am going to pluck up the courage to do it sometime in the near future after I install the fuel manager.

I think i will have to add this to list of mods to do,would certainly take a fair bit of strain off of the injector pump

I need of some help...a bit confused. Sorry my English is not the best.
I'm confused on how to re rout the small hose to the return. Can anyone explain in a very simple / plane way?.
Instructions for dummies.

One more thing. I'm also installing a second filter should I put this filter first or after the factory filter?

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Originally Posted by 05Y61

One more thing. I'm also installing a second filter should I put this filter first or after the factory filter?

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Depending on what micron the second filter is. The main filter will be around 8 micron, brand depending. So if your new filter has finer filtration ability, i.e 8 micron or less, it will need to be after the main filter, to catch what the main filter is unable too, if its like a 15 or 30 micron, before the main filter, to catch the larger particles to assist the main, finer, filter.

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Originally Posted by mudski

Depending on what micron the second filter is. The main filter will be around 8 micron, brand depending. So if your new filter has finer filtration ability, i.e 8 micron or less, it will need to be after the main filter, to catch what the main filter is unable too, if its like a 15 or 30 micron, before the main filter, to catch the larger particles to assist the main, finer, filter.

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Makes sense. Otherwise you would quickly clog the first (finer) filter and have a big restriction. Thanks for the explanation.