How to keep a d22 with 386000kms on it going strong?

[alfric]

Hi all. I’m looking for some clues on what to do to keep my 2006 d22 ZD30 single cab going strong. It’s been super reliable for 386000kms, lots of long distance touring on dirt and corrugations, never missed a beat. I drive it very conservatively, serviced every 10000 and now every 5000 for the last few years. Driveline is all good, new clutch three years ago, new neutral position switch recently, old man emu suspension (50mm lift) recently, new radiator recently. Gearbox/transfer case, uni-joints, steering/linkages, suspension, CV joints etc I’m ok with assessing myself, the engine not so much. I’m almost clueless about directing the work on a turbo diesel. So i’m in a mechanics hands, which is not such a good feeling. I’m thinking; timing chain, turbo and getting EGR system/inlets cleaned out, new EGR valve, vacuum tubes checked over, a catch can installed etc. I’m assuming oil pressure is super important with the turbo and perhaps the oil pump should be done with the timing chain? wondering if at this many kms it’s just simply a time for a engine rebuild, be good to avoid that unless there is cracked piston or some such, which I’m hoping to avoid with work done now……Am I missing anything?…….Happy to spend some dosh and would like to keep as stock and legal as practical. I know this is a pretty vague question but…any pointers would be great. Cheers.

 

[Horatius]

I've got one similar, though the kms on mine are a bit misleading as it's done so much off road where it can do a lot of work for not many kms, also had the speedo wires ripped off a couple of times. If it ain't broke don't fix it are my thoughts. Unless it has obvious problems or is using lots of oil or something. From experience rebuilt engines can be disappointing.

I cleaned the inlet manifold a while back, the relevant ports were all but completely blocked. Made no discernible difference to anything of course and I'm wondering if I should have just let that part of the manifold block completely.

What you have been doing obviously works, so I'd just keep doing that until it shows obvious signs that it's on the way out. Could get a while out of it yet. Though they don't last forever and eventually you'll have to decide whether a repair or new ute is the best option. Unfortunately I have doubts the later model utes are going to be as high mileage.

 

[alfric]

Reading through some D22 ZD30 posts and it sounds like doing the injector pump might also be a good idea!. Is there any way to test it?

 

[alfric]

Cheers Horatius. I agree with your doubts about later model utes. Figuring that keeping it going is currently cheaper than starting again, given the current prices secondhand and new.

 

[Horatius]

There is a way to check fuelling via electronic gadgetry (lol) afaik, there'll be posts on here about it. Though replacing that is big money and they have been known to go at low kms also. So it might not be worth doing that as a preventative measure. Keep changing the filters regularly is the best thing you can do.

 

[nuthanav]

G'day alfric, I can understand your concerns with the figures of 386000k's on a ZD30. I agree with Horatius, in general "if it aint broke, don't fix it". Mine has done 492xxxk's. It's still very strong. Even though its been "put to work" at times, its been operated at all times inside its envelope. With the right attitude these engines can go the distance. Mine has been a very good ute. My recipe has always been:-
Service it every 10000ks without fail, or less if worked hard.
Only use good fuel, and fuel filter. Filter life 10000ks max, less if you're working hard.
Only use good oil. Filter life as for the fuel filter. The sumps are small.
If you work it hard, watch the temp gauge, these heads are fragile. Make sure the coolant level is right.
Work it inside "the envelope."
As to your fuel pump question, I dont think there is any way of testing/checking its condition prior to a failure. At 386000K's, a replacement before the inconveninece of a failure may be prudent. Do the injectors with the pump too. Mine failed with no prior warning, but at 478000K's I couldn't complain.
If you have 386000k's out of yours so far, given my experience, I'd say there's likely a bit more to be got out of it yet. Get a catch can on it but with those K's I'd be getting all the intake system off it and cleaning it back to like new condition. Do the swirl mod also. Plenty of info on that on the website.
Good luck.

 

[alfric]

G'day alfric, I can understand your concerns with the figures of 386000k's on a ZD30. I agree with Horatius, in general "if it aint broke, don't fix it". Mine has done 492xxxk's. It's still very strong. Even though its been "put to work" at times, its been operated at all times inside its envelope. With the right attitude these engines can go the distance. Mine has been a very good ute. My recipe has always been:-
Service it every 10000ks without fail, or less if worked hard.
Only use good fuel, and fuel filter. Filter life 10000ks max, less if you're working hard.
Only use good oil. Filter life as for the fuel filter. The sumps are small.
If you work it hard, watch the temp gauge, these heads are fragile. Make sure the coolant level is right.
Work it inside "the envelope."
As to your fuel pump question, I dont think there is any way of testing/checking its condition prior to a failure. At 386000K's, a replacement before the inconveninece of a failure may be prudent. Do the injectors with the pump too. Mine failed with no prior warning, but at 478000K's I couldn't complain.
If you have 386000k's out of yours so far, given my experience, I'd say there's likely a bit more to be got out of it yet. Get a catch can on it but with those K's I'd be getting all the intake system off it and cleaning it back to like new condition. Do the swirl mod also. Plenty of info on that on the website.
Good luck.

Hi nuthanav, thats all good to hear. It was serviced every 10000 from it’s birth to about the end of 2013, I ignored it a bit and missed a service ( still had an oil change or two though) when I first got it from the old man but was only doing slow easy commutes to job sites around town. bit rough on it but never ever thrashed it and always kept it in the ‘envelope’. Since 2015 I felt bad about ignoring it and started doing them every 5000. Had a major going over in 2019, guy had a look inside and said it was the cleanest looking engine he’d seen for ages. That made me feel a bit better. Currently doing very light duties and booked in next week for inlet clean, turbo replace, catch can, timing and a full engine check over. Certainly will have a look at swirl mod but would be apprehensive about doing myself and also would need to feel like I understand it fully before doing it. Pretty sure I’ll get a 2.5” or 3” exhaust upgrade to let it breath a bit better. At least from there I’ll know the engine is safe enough, if the injector pump goes, yes, it’s an inconvenience (more or less, depending on where it happens!) I’m keeping in mind I never actually paid for the old girl in the first place, so see how it all adds up and maybe fuel system should be on the cards too. Learnt a lot from this forum over the last couple o months, will have to give a bit back soon. Cheers

 

[Oldie]

2003 D22 with a brilliant ZD30 motor. Ticked over to 476,100 k's a few days ago.
This is the only tips I can give. They like fresh oil. Usually about every 5K or when I see it going slightly black. Then it's oil and filter change. I have learnt you will feel it in the motor performance when it needs new oil.
Depending on where you are, I also change the air filter. I haven't been driving on dirt roads for a few years, only Perth metro, so air filter every 12 months.
3 inch exhaust also helps and an ECU reset. If I can find the instructions I got for the ECU reset, I'll post them but the old girl took off like a rocket after I did it hahaha
Apart from that, if it ain't broke then don't fix it.
Cheers and Beers

 

[Oldie]

Forgot to say, put an intercooler on it if it doesn't have one.
i put an FFI winch version on mine and it works fine.

 

[alfric]

Forgot to say, put an intercooler on it if it doesn't have one.
i put an FFI winch version on mine and it works fine.

I’ve considered an intercooler, front mount seems the way to go but not sure it will fit without removing the aircon unit. I guess with a top mount I could get another bonnet with the slot in it. easy enough. mmm. I’ll start with getting turbo swapped out for a new one and a fatter exhaust. I’m wondering if ECU reset for my 2006 is as simple as disconnecting neg lead on the battery and running remaining power out? Or the peddle dance thing?

 

[Erick]

The reason it’s still going is because as u say u drive it between its boundaries. Start playing with it, intercoolers, exhausts and whatever and u reduce its life. It’s a diesel, not a race car. Lots of Diesel motors do millions of kms if they are driven and serviced competently. My zd30 is coming up to 300k and has a lot of life in it yet, judging by condition of its oil and smooth running. There is never a reason to rev a zd30 beyond 2700 rpm-which is highway speed- in any gear. Going over that just causes bad fuel economy and temperature issues

 

[Newnav100]

The reason it’s still going is because as u say u drive it between its boundaries. Start playing with it, intercoolers, exhausts and whatever and u reduce its life. It’s a diesel, not a race car. Lots of Diesel motors do millions of kms if they are driven and serviced competently. My zd30 is coming up to 300k and has a lot of life in it yet, judging by condition of its oil and smooth running. There is never a reason to rev a zd30 beyond 2700 rpm-which is highway speed- in any gear. Going over that just causes bad fuel economy and temperature issues

Adding an intercooler and a free flowing exhaust will add to its life not reduce it.

 

[Been a while]

Lol, they're not alive until 3000rpms

 

[Erick]

Think the factory would have done that if it was true. Certainly didn’t work for the patrol motors.

 

[Newnav100]

Think the factory would have done that if it was true. Certainly didn’t work for the patrol motors.

Can’t speak for the patrol motors . Pretty sure same block different design. Cost is the most likely factor

 

[redkite]

Patrol ZD30's failed because they were overheating. Navara ZD30's usually dont fail with the same engine block, because they have no intercooler, so they get less air, and the ECU gives them less fuel.

Since they burn less fuel, they produce less power, but also less heat. And heat is what kills all machines in the end.

Sure you can improve the power output of a Navara ZD30 with an intercooler and wider exhaust. But it will limit its lifetime. (And depending on the build-year, you might have a ZD30 block that fails even earlier due to cooling duct mistakes by Nissan (which popped up in the hotter Patrol engines, not in the cooler Navaras)).

Sure you can cruise in your Navara at 4000rpm. But even a 3rd grader understands that the engine wears twice as fast at 4000rpm as at 2000rpm.

However, it all depends on what your goal is.

 

[Horatius]

The Patrols seem to have had design and sensor issues that caused them to over boost and over fuel (and get over stressed/ too hot), with predictable results. There could be a message in that for the aware lol, but putting a little four cylinder motor in them and working the guts out of it was never a good idea to begin with. They should have gone the way Toyota did with the Land Cruiser and gave them a V8.

I doubt an intercooler (or larger exhaust) is going to make much difference either way to longevity (driving style and maintenance seem to be the things), but I have doubts they'll do anything else much either, and tend to agree with the general principle that the closer to stock you can keep them the better it is (for longevity). Although some people have an intercooler not so much for performance, it offers at least some protection if the turbo fails catastrophically. Apart from the lack of a suspension system, the engineers seem to have got it reasonably good in the Nav.

It would be very rare that I rev out to 3000 rpm. Rather than flog it uphill and change gears (say from 3rd to 4th), only to then have to change back down again lol I'm more likely just to slow down and sit at 2500-2750 rpm until I get over the hill, then change. At a certain point somewhere around 3000 rpm it doesn't seem to matter what you do anyway. They only get so much boost and fuel and are way under tuned, which is a good thing IMO (for longevity). They're no performance car, but compared to the old naturally aspirated diesels they certainly feel like it!

Something I never quite understood re intercoolers (I'm nothing if not an ***** lol) is the claim that it helps the motor run cooler (lower egt's for instance). Not sure why a slight difference in intake air temp has much bearing at all on the temperature the diesel combusts at in the cylinders? I can see where you might get slightly more Oxygen and hence catalyst (in certain circumstance's) with a possible measurable increase in efficiency, but I'm not sure why this wouldn't make them combust more completely/ slightly hotter if anything? Perhaps the extra efficiency means they don't have to work quite as much? Perhaps thermodynamics isn't my thing lol?

 

[BarneyB]

Think of the intercooler as "air density modifier".
The change (hopefully reduction) in intake temperature is just a function of the real design brief - which is to increase the density of the charge air and then inject slightly more fuel to match.
As for longevity of the engine with/without? That's not easily answered in a black or white manner IMO. There's a few variables that might affect the outcome in each specific application.

Now, would I tune/modify/upgrade a reliable D22/YD25 with 386k on the speedo? Nope.

 

[Horatius]

Think of the intercooler as "air density modifier".
The change (hopefully reduction) in intake temperature is just a function of the real design brief - which is to increase the density of the charge air and then inject slightly more fuel to match.

Yep. Basically cooler air will contain more oxygen than the same volume of warmer air, because it contracts (and warmer air expands).

The part I'm not getting is the claim that this reduces egt's. As to the "more fuel", that seems at odds with the design idea, which is ultimately to use less fuel?

ps. the op has a zd30 model, but I still agree wit your point.

 

[BarneyB]

Yep. Basically cooler air will contain more oxygen than the same volume of warmer air, because it contracts (and warmer air expands).

The part I'm not getting is the claim that this reduces egt's. As to the "more fuel", that seems at odds with the design idea, which is ultimately to use less fuel?

ps. the op has a zd30 model, but I still agree wit your point.

Oops. I'm a plonker. ZD30 has only been mentioned about 50 times!

Reduced EGT's ? Hmmm....maybe on a hot day, under high load, the maximum EGT achieved might be lower because the cooler intake charge has a limiting effect when the engine is producing maximum heat ??
But under other conditions (cooler ambient, moderate load) it may increase EGT's because each combustion event is bigger than it would have been with a thinner/hotter charge of air & slightly less fuel ??

AFAIK intercoolers (or charge air coolers in other industries) were/are primarily for increased performance, not fuel economy.
Same with a T/C. The volumetric efficiency goes up for a given displacement...but absolute fuel consumption is almost always higher.