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Diesel Injectors - When to clean?

Posted: Thu Jan 08, 2009 7:56 pm
by danos
Ive got a 98 3LD hilux at about 190k and am wondering when/if I should get the injectors cleaned.

The car doesnt blow any smoke at all so im assuming they are in good nick. Its due for another timing belt soon as well.

Cheer
Dane

Re: Diesel Injectors - When to clean?

Posted: Thu Jan 08, 2009 9:13 pm
by bogged
danos wrote:Ive got a 98 3LD hilux at about 190k and am wondering when/if I should get the injectors cleaned.

The car doesnt blow any smoke at all so im assuming they are in good nick. Its due for another timing belt soon as well.

Cheer
Dane
some places recommend they be done ea 100k.. It maybe time, it may improve fuel economy and power, but it may just cost you a lot of coin for nothing... you could try some injector cleaner, but IMWO its more of a placebo.

but if your happy it isnt blowing smoke, then leave it.

Posted: Fri Jan 09, 2009 1:47 am
by zagan
Got my diesel pump rebuilt at 200,000klms got told injectors are still good for another 50,000klms.

Smoke is the general sign for when they need changing.

Other way to go is to buy a injector test pump and see what the spray is like.

Posted: Fri Jan 09, 2009 7:22 am
by JWB
How long have you had the car?
Have they been done before?
Standard interval is 100k, That said it depends on fuel quality and
this distance can be easily halved if sucking fuel from drums out bush.
If you have not done them since you have had the car
I think getting their spray pattern checked would be a good start.
If you don't know the full service history & funds allow, I would
get em done before the timing belt.
cheers

Posted: Fri Jan 09, 2009 8:23 am
by danos
Ok

Ive had the car for just over 2yrs from 153k to 190k and have not checked the service history.

I'll enquire about getting the spray pattern checked.

Cheers

Posted: Fri Jan 09, 2009 8:25 pm
by Shadow
JWB wrote:How long have you had the car?
Have they been done before?
Standard interval is 100k, That said it depends on fuel quality and
this distance can be easily halved if sucking fuel from drums out bush.
If you have not done them since you have had the car
I think getting their spray pattern checked would be a good start.
If you don't know the full service history & funds allow, I would
get em done before the timing belt.
cheers
Standard interval is certainly not 100k on a 98 hilux. (might say that in the toyota manual, but they most certainly do not need doing every 100k)

My HJ60 landcruiser went 420thousand on its origonal set and still had no problems with injectors, rebuilt engine so did injectors at the same time. The mechanic said they were not that bad, but i did them anyway, figured 400thousand was long enough.

The important things are, Direct injection or Indirect injection, and how old.

Direct injected engines need thier injectors maintained much more than indirect.

Ive seen several 3litre turbo diesel engines in coasters that go 500thousand on the same injectors. The guy runs the toyota injector cleaner every second tank, and swears by it.

Im not familiar with the hilux engines, is the 3.0l diesel direct or indirect?

Posted: Fri Jan 09, 2009 8:43 pm
by JWB
So sorry for giving MY view :roll: even if somewhat clouded.
The 100 k statement was a general statment regarding my vehicle ( GQ TD42 ) not directly aimed at the 3lt.
I'm not that familiar with the 3lt engine but I was presuming it was indirect
injection ( Could be wrong tho )
I wouldn't expect any good mechanic would put old injectors on freshly built diesel motor. unless he closely knew the engine/components.

cheers

Re: Diesel Injectors - When to clean?

Posted: Sat Jan 10, 2009 9:48 am
by KiwiBacon
bogged wrote:
danos wrote:Ive got a 98 3LD hilux at about 190k and am wondering when/if I should get the injectors cleaned.

The car doesnt blow any smoke at all so im assuming they are in good nick. Its due for another timing belt soon as well.

Cheer
Dane
some places recommend they be done ea 100k.. It maybe time, it may improve fuel economy and power, but it may just cost you a lot of coin for nothing... you could try some injector cleaner, but IMWO its more of a placebo.

but if your happy it isnt blowing smoke, then leave it.
I had my injectors done last year at great cost.
The place that did it said one was very bad (probably the one that showed a wet exhaust port if the vehicle was just started, moved and shutdown still cold), one was bad and the other two were borderline.

Improvement in faint blue smoke when cold was there, but this coincided with a turbo swap so the results are inconclusive.
Otherwise it was a wash. Fuel economy didn't change, ease of starting didn't change.

IMO servicing injectors every 10,000km is like chaning your oil every 5000km. Fine for the paranoid or retired but the rest of us have better things to spend our time and money on.
I'll now sit back and await the "it's cheap insurance" comments. To which I answer it's neither cheap, nor insurance.

I hear a lot of "poor quality fuel" comments, but few people can say what is poor quality about their fuel or exactly what it was in the fuel that supposedly caused the damage.

Posted: Sat Jan 10, 2009 10:25 am
by Micky-Lux
From what I understand and have been told, it's not just the nozzles that wear causing irregular spray pattern and leakage, its also the springs inside that over time lose their tension or sag, causing an injector pulse that is not quite ideal.

That said, I had mine done at 130000, I was doing other work anyway so it was easy to have them done at the same time. I removed them myself, and it cost $200 to have them reco'd to original specifications. Hard to say whether it gave an increase in horsepower as I also fitted a turbo at the same time.

But for peace of mind, I know everything is running as it should. (The valve clearances at the same time were out by a maximum of .01mm - not worth touching.)

What might work for one engine may not work as well for another, even if they are the same type. Like said in a previous post, it depends on usage, fuel quality, etc. etc. If you're worried about them, get them looked at.

Re: Diesel Injectors - When to clean?

Posted: Sat Jan 10, 2009 10:32 am
by Micky-Lux
[quote="KiwiBacon]

IMO servicing injectors every 10,000km is like chaning your oil every 5000km. Fine for the paranoid or retired but the rest of us have better things to spend our time and money on.
I'll now sit back and await the "it's cheap insurance" comments. To which I answer it's neither cheap, nor insurance.

I hear a lot of "poor quality fuel" comments, but few people can say what is poor quality about their fuel or exactly what it was in the fuel that supposedly caused the damage.[/quote]

Changing injectors every 10000km is over the top. Changing oil every 5000km is not. The book service states that the service is 5000km. Diesels are notorious for producing more carbon and crap in the oil than a petrol. Leave it in there for long enough and you block oil galleries, not to mention it's abrasive properties. Therefore I think the 5k service is reasonable.

And the poor quality fuel we speak of has amongst other things to do with dirt content, water, other contaminants. Underground tanks at servos are notoriously dirty, especially in wet weather or humid climates. Go to Cairns or Darwin and it's bloody hot and humid up there. All that moisture eventually collects in the underground tanks, which can, in turn end up in your tank and through your injectors.

Posted: Sat Jan 10, 2009 10:35 am
by nicbeer
this the same for petrol injectors?

my subi is coming up for 120 thou and considering getting them cleaned and flow tested.

i had this done to my old proton at similar k's and it made a diference.

Re: Diesel Injectors - When to clean?

Posted: Sat Jan 10, 2009 11:27 am
by KiwiBacon
Micky-Lux wrote: Changing injectors every 10000km is over the top. Changing oil every 5000km is not. The book service states that the service is 5000km. Diesels are notorious for producing more carbon and crap in the oil than a petrol. Leave it in there for long enough and you block oil galleries, not to mention it's abrasive properties. Therefore I think the 5k service is reasonable.

And the poor quality fuel we speak of has amongst other things to do with dirt content, water, other contaminants. Underground tanks at servos are notoriously dirty, especially in wet weather or humid climates. Go to Cairns or Darwin and it's bloody hot and humid up there. All that moisture eventually collects in the underground tanks, which can, in turn end up in your tank and through your injectors.
That reference to oil changing every 5000km wasn't in regards to old indirect injection toyotas.
My diesel work car has oil change intervals of 20,000km (from the book), yet the only time I paid someone to change the oil, they put a "next oilchange due in 5000km" on the window.

Good diesel filters have a bypass filter inside them, this filters out the bigger abrasive carbon lumps and can in some situations clean your oil to a state better than it was on delivery.
If you think your oil needs changed at 5000km, why not sample it and see? It could give early warning of an expensive problem. Money spent on oil sampling is indeed insurance, money spent changing oil not-so.

As for water and dirt in fuel, that's why they invented water traps and fuel filters. Contaminated fuel and "poor quality" fuel are two different issues.

Posted: Sat Jan 10, 2009 10:40 pm
by Micky-Lux
Contaminated or poor quality fuel?

At times, especially when travelling, you don't know what you'll end up with. And even the best water traps and filters won't remove 100% of the crap.

My work vehicle (VDJ79 Cruiser) gets an oil change/service every 10,000 kms. I'm not paying for it, and I don't have to worry about how long it lasts. But I do my own (both the Lux, and my other car, V6 Crummydore) every 5000km. I buy the oil by the 20l drum, so costs farkall. And the inside of the engine is still reasonably clean too. I don't like waiting for the oil to look like vegemite before I change it.

If I had a caterpillar diesel, like some of the big gensets I work on, where they can cost up to $200 in oil every change, I'd test it first. But we're only talking 5-7 litres per change here.

But on a totally different spin, my old sierra used to cost on average 50 bucks for an oil change. The motor had over 260,000 on it. Every change, the oil looked like crap, the inside of the rocker cover was full of gunge, and god knows what the bottom end looked like. I had a mate that had another engine that I could have anytime for $100. So I gave up doing oil changes on that car. I figured I'd only have to skip two to be even, three to be in front. I did over 65,000kms without an oil change, and the engine did not look like giving up the ghost. I sold it with over 330,000kms on the clock, and as far as I know, it still goes. That said, I would not drive it to the cape and back like that. A little bit risky...

I guess with injectors, it depends on how much it costs to have them reco'd. Like I said, it only cost me $200 to have mine done, plus a bit of my own time to r&r them. That's only 3 cartons of bundy these days.

Posted: Sun Jan 11, 2009 1:27 am
by zagan
nicbeer wrote:this the same for petrol injectors?

my subi is coming up for 120 thou and considering getting them cleaned and flow tested.

i had this done to my old proton at similar k's and it made a diference.
No you can clean them out to get extra life on petrol injectors.

You only goto new injectors if you want to or want larger ones for extra boost or modded engine etc.

Diesel injectors can only be replaced as the holes in them get bored out larger and then they don't really vaporise the diesel fuel properly and just squirt fuel, which shows up at the back end as extra smoke so when you start to see smoke coming out the exhuast you might want to check out the injectors.

Petrol injectors only do 10 to 50PSI out of them so it never really bores them out.

Where as old diesel injectors are doing 50,000PSI and the brand new motors with ECU injectors are doing over 100,000PSI.

You need the extra PSI or the diesel fuel can't be injected into the motor it'd actually push the diesel out the injector and into the pump, it's from the much higher compression ratio on diesels.

Motorbike injectors are an inbetween of petrol/diesel injectors they get chewed out as well but only because of the high RPMs and the slightly higher than petrol motor compression ratio so they usually get replaced around the 50,000klm mark if your've got a brand new bike.

Posted: Sun Jan 11, 2009 1:32 am
by zagan
Micky-Lux wrote:Contaminated or poor quality fuel?

At times, especially when travelling, you don't know what you'll end up with.

I guess with injectors, it depends on how much it costs to have them reco'd. Like I said, it only cost me $200 to have mine done, plus a bit of my own time to r&r them. That's only 3 cartons of bundy these days.
I take it your talking about petrol which is just a good clean out with some solvents.

Re: Diesel Injectors - When to clean?

Posted: Sun Jan 11, 2009 1:42 am
by zagan
KiwiBacon wrote:
Micky-Lux wrote: Changing injectors every 10000km is over the top. Changing oil every 5000km is not. The book service states that the service is 5000km. Diesels are notorious for producing more carbon and crap in the oil than a petrol. Leave it in there for long enough and you block oil galleries, not to mention it's abrasive properties. Therefore I think the 5k service is reasonable.

And the poor quality fuel we speak of has amongst other things to do with dirt content, water, other contaminants. Underground tanks at servos are notoriously dirty, especially in wet weather or humid climates. Go to Cairns or Darwin and it's bloody hot and humid up there. All that moisture eventually collects in the underground tanks, which can, in turn end up in your tank and through your injectors.
That reference to oil changing every 5000km wasn't in regards to old indirect injection toyotas.
My diesel work car has oil change intervals of 20,000km (from the book), yet the only time I paid someone to change the oil, they put a "next oilchange due in 5000km" on the window.

Good diesel filters have a bypass filter inside them, this filters out the bigger abrasive carbon lumps and can in some situations clean your oil to a state better than it was on delivery.
If you think your oil needs changed at 5000km, why not sample it and see? It could give early warning of an expensive problem. Money spent on oil sampling is indeed insurance, money spent changing oil not-so.

As for water and dirt in fuel, that's why they invented water traps and fuel filters. Contaminated fuel and "poor quality" fuel are two different issues.
That'd be using pure synthic oils though, I've used penrite synthic diesel oil great stuff got 30,000+klms out of it, started getting the oil tick so had to grab something cheap so got some of that nulon mineral diesel oil to try out.

I don't think it's worth the cash even cheap as the oil tick is coming on again after 2-3,000klms, which is disappointing really you'd think it'd last for around 5,000klms at least.

I'd normally use GTX diesel mineral oil which lasts around 6-7,000klms before getting oil tick.

Though I'd be more than happy to go synthic again but at $100+ for 10litres it's a bit XXXy though you do get the extra klms out of a oil change so it's a toos up I guess.

Re: Diesel Injectors - When to clean?

Posted: Sun Jan 11, 2009 8:02 am
by KiwiBacon
zagan wrote: That'd be using pure synthic oils though, I've used penrite synthic diesel oil great stuff got 30,000+klms out of it, started getting the oil tick so had to grab something cheap so got some of that nulon mineral diesel oil to try out.

I don't think it's worth the cash even cheap as the oil tick is coming on again after 2-3,000klms, which is disappointing really you'd think it'd last for around 5,000klms at least.

I'd normally use GTX diesel mineral oil which lasts around 6-7,000klms before getting oil tick.

Though I'd be more than happy to go synthic again but at $100+ for 10litres it's a bit XXXy though you do get the extra klms out of a oil change so it's a toos up I guess.
Nope, that's using any normal 15w40 diesel engine oil. Why would nissan suggest their van/ute motors get fully synthetic oil?

Oil tick?

BTW, peak compression pressures on a diesel are only 500psi or so. The extra high pressure is to get a faster and cleaner burn to meet the every tighter emissions laws.
The three potential problems with injectors are wear of the nozzles, clogging of the nozzles and opening pressure changing.
A mere clean and resetting of the injection pressure might not cost you much. But changing the tips can get very expensive.

Some simple maths.
200,000km vehicle life.
Say 8 litres of oil and a couple of filters cost you $100. Neglecting of course the time that it takes you or the person you pay to change it.

Changing oil every 5000km will cost you $4k in oil and filters.
Changing oil every 10000km will cost you $2k in oil and filters.

Now show me a problem caused by oil changes at 10,000km intervals which a 5,000km interval is guaranteed to prevent.

Posted: Sun Jan 11, 2009 8:57 pm
by Micky-Lux
zagan wrote:
Micky-Lux wrote:Contaminated or poor quality fuel?

At times, especially when travelling, you don't know what you'll end up with.

I guess with injectors, it depends on how much it costs to have them reco'd. Like I said, it only cost me $200 to have mine done, plus a bit of my own time to r&r them. That's only 3 cartons of bundy these days.
I take it your talking about petrol which is just a good clean out with some solvents.
Hi Zagan,

I've been unfortunate enough to end up with both bad diesel and petrol at times... And not aways been able to clean out with solvents either. Fortunately they're relatively few and far between.

I had an SS Commodore once, that I filled with premium at the Caltex in Singleton on my way to Sydney one night. Whatever was in the fuel that night gummed up my injectors, fuel lines and filters, as well as taking the coating off the inside of the tank, which left corrosion that caused no end of problems. I sold that car less than two months later because I simply couldn't afford to keep fixing it. I think it was about 12 months later Caltex had problems with their avgas and light aircraft that did the same thing. I wonder if it was the same sort of contamination?

Posted: Sun Jan 11, 2009 8:58 pm
by Micky-Lux
Hey Kiwi -

I'd like to think I'm going to get more than 200,000km from my car ;)

Re: Diesel Injectors - When to clean?

Posted: Sun Jan 11, 2009 9:38 pm
by brad-chevlux
KiwiBacon wrote: Some simple maths.
200,000km vehicle life.
Say 8 litres of oil and a couple of filters cost you $100. Neglecting of course the time that it takes you or the person you pay to change it.

Changing oil every 5000km will cost you $4k in oil and filters.
Changing oil every 10000km will cost you $2k in oil and filters.

Now show me a problem caused by oil changes at 10,000km intervals which a 5,000km interval is guaranteed to prevent.
Hilux 2.8L spun big end bearing on number 4 rod.

cruiser 1HZ spun big end bearing on number 5 rod.

both cost way more then $2000 to fix.
both had less then 200 000km
both had oil changed between 10 000km and 15 000km
both had blockages in oil passages
both owners now change oil every 5000km.

it might not happen to every engine, but it can and does happen to some.

Posted: Mon Jan 12, 2009 5:19 am
by KiwiBacon
Micky-Lux wrote:Hey Kiwi -

I'd like to think I'm going to get more than 200,000km from my car ;)
Me too. But a surprising amount end up shiney side down, shortened or otherwise unusable by that stage.

Re: Diesel Injectors - When to clean?

Posted: Tue Jan 13, 2009 10:13 pm
by zagan
Your orignal post
KiwiBacon wrote: My diesel work car has oil change intervals of 20,000km (from the book), yet the only time I paid someone to change the oil, they put a "next oilchange due in 5000km" on the window.
Next post
Now show me a problem caused by oil changes at 10,000km intervals which a 5,000km interval is guaranteed to prevent.
How old is this work car as the new Diesel motors over the last 2-3 years are now swapping over to 100% synthic oil only.

Are you changing oil at 20,000klm or 10,000klms I could see nissan saying 10,000klms but not 20,000klms but the nissan dealership must be using semi-synthic, as mineral oil goes fairly quick after 5,000klms.


As for oil tick... all motors once the oil becomes done, start to tick and keeps getting worse over time untill it's changed.

Re: Diesel Injectors - When to clean?

Posted: Tue Jan 13, 2009 11:20 pm
by ISUZUROVER
zagan wrote: As for oil tick... all motors once the oil becomes done, start to tick and keeps getting worse over time untill it's changed.
????????????????????????

"done" wtf is that supposed to mean???

Re: Diesel Injectors - When to clean?

Posted: Wed Jan 14, 2009 4:21 am
by KiwiBacon
zagan wrote: How old is this work car as the new Diesel motors over the last 2-3 years are now swapping over to 100% synthic oil only.

Are you changing oil at 20,000klm or 10,000klms I could see nissan saying 10,000klms but not 20,000klms but the nissan dealership must be using semi-synthic, as mineral oil goes fairly quick after 5,000klms.
This work car is 2000 model year. It does not use or specify synthetic oil anywhere. I change oils at 20,000km in that vehicle.
Mineral oil goes nowhere after 5000km, what exactly are you talking about?
zagan wrote: As for oil tick... all motors once the oil becomes done, start to tick and keeps getting worse over time untill it's changed.
I have never experienced this and I've seen some engines that are virtually running on tar. I think your engine has issues.

Re: Diesel Injectors - When to clean?

Posted: Wed Jan 14, 2009 10:19 am
by Shadow
KiwiBacon wrote:
zagan wrote: As for oil tick... all motors once the oil becomes done, start to tick and keeps getting worse over time untill it's changed.
I have never experienced this and I've seen some engines that are virtually running on tar. I think your engine has issues.
i think hes talking about tappets ticking because they are not getting oil?

Posted: Wed Jan 14, 2009 5:27 pm
by Micky-Lux
The new V8 cruisers are the perfect company car. You never have to check the oil.

There's an orange warning light that comes on when the level's low. If the red light comes on, it's really low. Kind of idiot proof really.

Posted: Wed Jan 14, 2009 10:07 pm
by coxy321
Micky-Lux wrote:The new V8 cruisers are the perfect company car. You never have to check the oil.

There's an orange warning light that comes on when the level's low. If the red light comes on, it's really low. Kind of idiot proof really.
My co-worker doesn't check the oil in his Camry until the light on the dash comes up.

Monday morning on his way to work he grabbed a big end bearing - he thought the noise was a stick caught under the front somewhere :roll:

I service my diesel at 5000km, and EVERY 5000km. No ifs buts or maybe's. I can't afford to skimp on a $100 service only to receive a $7000+ repair bill.

Posted: Thu Jan 15, 2009 5:59 am
by KiwiBacon
coxy321 wrote: I service my diesel at 5000km, and EVERY 5000km. No ifs buts or maybe's. I can't afford to skimp on a $100 service only to receive a $7000+ repair bill.
What is your diesel and why would it cost $7k to repair. You can replace most motors for far less than that.
Will your 5000km services guarantee that you never have to spend that $7k? It seems most of the engines with frequent change intervals have other expensive issues. Like cracking heads or big end bearings that eat into cranks.

I had a workmate once who was getting the timing belt replaced in his Mazda 323 (mid 80's model) because someone told him it would cost $3500 to fix the engine if the timing belt broke.
I asked him why you'd spend $3500 to repair a $200 motor, then the workshop called and told him his car had a timing chain. :roll:

Posted: Thu Jan 15, 2009 8:12 am
by coxy321
KiwiBacon wrote:
coxy321 wrote: I service my diesel at 5000km, and EVERY 5000km. No ifs buts or maybe's. I can't afford to skimp on a $100 service only to receive a $7000+ repair bill.
What is your diesel and why would it cost $7k to repair. You can replace most motors for far less than that.
Will your 5000km services guarantee that you never have to spend that $7k? It seems most of the engines with frequent change intervals have other expensive issues. Like cracking heads or big end bearings that eat into cranks.

I had a workmate once who was getting the timing belt replaced in his Mazda 323 (mid 80's model) because someone told him it would cost $3500 to fix the engine if the timing belt broke.
I asked him why you'd spend $3500 to repair a $200 motor, then the workshop called and told him his car had a timing chain. :roll:
As per my sig, its a TD42. Just had a look, a re-coed exchange motor will cost $3500, plus put ontop of that new injectors ($500?), pump reco, gaskets/seals, lubricants, and all of the other usual things you would do with a fresh motor, and then add labour and i think you'd be close to $5500.

A drive in - drive out would be easily $7000, however you could go the second hand route.

I dont think i was far off when i said a TD42 costs around $7000 to get someone to do a rebuild (complete).

Posted: Thu Jan 15, 2009 8:33 am
by KiwiBacon
coxy321 wrote: As per my sig, its a TD42. Just had a look, a re-coed exchange motor will cost $3500, plus put ontop of that new injectors ($500?), pump reco, gaskets/seals, lubricants, and all of the other usual things you would do with a fresh motor, and then add labour and i think you'd be close to $5500.

A drive in - drive out would be easily $7000, however you could go the second hand route.

I dont think i was far off when i said a TD42 costs around $7000 to get someone to do a rebuild (complete).
Fair enough, but once you'd spent the $7k you'd be further ahead than you are now. Do the TD42's run a bypass filter?