1HZ: injection pump and injectors - when to inspect?

Discussion in 'Diesel Tech and 24 volts Systems' started by rstl99, Mar 22, 2010.

  1. rstl99

    rstl99

    Messages:
    286
    Location:
    Ottawa, Canada
    Hi all,
    My 92 80-series with 1HZ has about 220,000 kms on it. Starts and runs very well, just changed the timing belt and tensioner on it to baseline that.

    I was browsing on the Lcool site and indications there seemed to suggest that on 1HZ engines (and possibly other similar Toyota diesels), the injectors themselves should be inspected/replaced at every 100,000 kms, and the injection pump about twice that.

    My truck is over the 200,000 kms level, and I don't have evidence in the few paper records that came with it that any work has been done on injectors or the IP. I'm not looking after work, but don't want to neglect something either.

    One of my mottos is "if it ain't broke, don't fix it", but I try to balance that with good attention to PM. Any thoughts or words of advice in this area? Thanks.
  2. DanS HJ-45

    DanS HJ-45 SILVER Star

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    4,165
    Location:
    Idaho Springs, CO
    I would personally leave it as it is for now. As you said: if it's not broken....

    I would have them tested/inspected if I was removing the IP for any reason whatsoever, or if it wasn't running right though.

    What's the worst that will happen if they are bad? If you can't afford having the truck down for a while for them to get rebuilt, then maybe do it as PM now.

    Dan
  3. rstl99

    rstl99

    Messages:
    286
    Location:
    Ottawa, Canada
    Sounds like a reasonable approach, thanks. At some point I'll inquire about a good diesel shop in Ottawa, where I could get this PM work done. I suppose I'm kind of used to the IP on my Mercedes 240D - IP's on those 240D/300D's basically outlast the rest of the engine/car. I gather the IP is not as long-lived on the Toyota diesels, 1HZ in particular.

    As to "what's the worst that can happen" question, here is a quote from one of the LCOOL post on the subject of injectors:

    If the injectors have not been overhauled in 260K km then they are WELL overdue.
    Diesel injectors are supposed to spray a finely atomised burst of fuel into the engine. If they are dirty or worn they will tend to squirt fuel instead. When squirted fuel ignites (explodes) inside the cylinder, it creates a hotspot. An extreme example of a hot spot will burn a hole through the top of a piston.
    I would strongly recommend replacement of the injectors with overhauled units.


    I would think that if my injectors were dirty or worn at 220k, I would feel sluggishness in the performance, or the truck would be occasionally hard to start. Likewise for wear on the IP. I'm always amazed how easily this 1HZ starts (mind you I don't drive it in winter): the glow circuit seems to come on only 3-4 seconds, then it starts up within 1 second of engaging the starter! Compared to 3B's I've owned, this is quite good!! ;) And the performance feels good to me, mind you I haven't driven any other 1HZ's, but the engine runs smooth and strong, 1HZ is much smoother than the 3B.
  4. Get those injectors tested... we have tested some here that are well under 100,000 km and the crack pressure and spray pattern was totally off.

    Use fuel additive with these pumps/injectors. I would suggest Stanadyne.

    ~John
  5. rstl99

    rstl99

    Messages:
    286
    Location:
    Ottawa, Canada
    Thanks for the advice on the additive, John, will go that route.

    As far as testing injectors, can any decent diesel shop do that? And if something is wrong with the spray pattern or crack pressure as you suggest, can they fix it or does one need to acquire new/rebuilt injectors?
  6. Tapage

    Tapage Club 4X4 Panamá SILVER Star

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    Panamá
    good signal of wornout injectors nozzles it's the black smoke .. but sure it depends on your amount of fuel ... if you already pull your injectors and they are off .. rebuild 'em ..

    I'm not sure if the 1HZ injectors are 2 stage as the 1HD-T injectors .. but usually the diesel shops around here just do the 1st stage rebuild ..
  7. There are only a few shops that have the machine to set up and test the two stage injectors.

    Although in many cases smoking and a slight loss of fuel economy and power indicate weak injectors, that's not always the case. We had a very low mileage HDJ81 in the shop about two weeks ago and the injectors mostly okay, but one was very bad. There was not tell-tale smoke or anything else wrong, but we tested them as part of a service package for Outback, and the results were interesting.

    Testing the injectors is easy with a test stand, rebuilding them needs expensive equipment.

    ~John
  8. The other problem tired injectors have is the springs get weak and open too early.Mine was doing this even though the spray pattern was satisfactory at their 100000klms change over (its a toyota service interval)

    Tired 1HZ pumps often work well at low speeds when cool,its when they are on the highway on warm days they show their true colours.
    The heat makes the pump expand and the plunger can no longer compress the fuel to the correct pressure.
    A diesel engine can only go as fast as the pump can squeeze fuel into it
  9. rstl99

    rstl99

    Messages:
    286
    Location:
    Ottawa, Canada
    Well, thanks again for the added thoughts and information on injectors and pump woes.

    Sounds indeed like it's a 100,000 kms service item, so I'll assume I'm due for something (unless I can find something in the rather thin service records that came with the truck).

    Ok, I'm sitting down: how much does a new (or rebuilt, if that's a safe way to go) set of 6 injectors for a 1HZ cost, should I decide to do the PM myself, and assume I can't get a local diesel shop to rebuild them? (I'll inquire though - are they 1 or 2 stage?)
  10. Your injectors are 2 stage.

    Send them to Fred Holmes Injection in Vancouver (google it).

    They should send you the correct installation seals (washers) when you get your "new" injectors back from them.

    ~John
  11. rstl99

    rstl99

    Messages:
    286
    Location:
    Ottawa, Canada
    Thanks John.

    Went finger-walking and called this local place who said they can test and clean the injectors for $35 each. He said if the truck doesn't smoke and runs well, likely a cleaning is all they need...

    [​IMG]

    I may start there, it's just a short drive from my place. They can also overhaul the pump whenever needed, but he said if the truck is running fine, don't touch it.

    Cheers.

  12. DanS HJ-45

    DanS HJ-45 SILVER Star

    Messages:
    4,165
    Location:
    Idaho Springs, CO
    Fascinating about the injectors being able to damage the engine. I guess I never really thought about diesel injectors being able susceptible to that. Turbine engine nozzles can screw up like that and cause big damage, but good to know about the 1HZ in particular.

    $35 a piece sounds like a great price to me. You don't want to know what the only N-D shop in town for me wanted to test an injector or rebuild a 3B IP....

    Dan
  13. Tapage

    Tapage Club 4X4 Panamá SILVER Star

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    John .. can you recomend work with any of those shops that can do the 2 stage rebuild ..? are expensive ( sure it is .. :) ) did you have any idea how much it will cost . ?

    I'm not sure about the lifespan of the 2stage of our injectors .. but sure aren't ready for the Cruiser life ..
  14. I have no idea how long they are supposed to last. The last set that was sent out was in the $900 range for 6 1HDT injectors as far as I recall - Outback Imports dealt with that end of it.


    Fred Holmes Injection in Vancouver, BC, Canada.


    Be sure to ask if they can do the two stage injectors !!!! Many shops cannot do it.

    ~John
  15. Tapage

    Tapage Club 4X4 Panamá SILVER Star

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    rebuild the 1st stage down here is around 500 bucks ( USD ) for 6 injectors .. no option here for the 2nd stage ..
  16. I dont think they clean too well. They have a fine teflon coating on them and when you clean it wears it away and you lose the spray pattern.
    Cleaning injectors is old school these days,they are just not designed for it.
    Spend $70 per injector by having them rebuilt and their done and good for 100000klms
  17. canucksafari

    canucksafari

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    9,090
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    Abby
    I suggest you get a quote for a local shop and also get a quote from Hiflo in Australia: Fuel Injectors (HiFlo Fuel Injection). They sell both new and rebuilt injectors for your engine. I know when I needed to get my injectors rebuilt, I got new ones for $300 less (including shipping) than what it would of cost to get mine rebuilt by Valley Fuel Injection.
  18. Tapage

    Tapage Club 4X4 Panamá SILVER Star

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    thanks .. I drop a mail, since I have no options for 2stage rebuild locally ..
  19. rstl99

    rstl99

    Messages:
    286
    Location:
    Ottawa, Canada
    Thanks Rosco, I didn't know that (coating). I must admit the guy who answered the phone at this place did not inspire great confidence - his response to any question I posed was "yeah". Not sure I want to pull the injectors, put them into his hands and hope they do a good job... :hmm:

    Thanks for the tip, I've sent them an email and will see what they come back with. I noticed on their site they list several injectors for the "80 Series 1HZ". Did they change over the years, or are they different manufacturers?...

    I did print the "recommended servicing - diesel fuel injectors" 1 page document they have on the site. It's interesting because I don't detect any of the "signs of injectors requiring service" on my truck. Mind you, I don't have another 80-1HZ to compare. Mine is night and day compared to the BJ60/3B I owned until last year. Plus, having come with meager service records, I'm sort of working blind trying to baseline it. Better safe than sorry I suppose. ;)

    The document did allude to the basic need of having a good fuel filter and sedimenter to prevent injector and pump damage. I'll be checking that very shortly. As their document states at the end, by taking good care of injectors, filters, sedimenter, "your pump should require very little service".

    And now that I'm tacking my 80/1HZ, my thought also turns to my '82 MB 240D slumbering in my garage (ie. when was the last time the injectors were looked at on THAT one - there are 300,000 kms on it!) :whoops:

    Oh well, diesels are still easier to look after than gas engines, right? :D
  20. 96r50

    96r50

    Messages:
    2,815
    PM lshobie or bvissers on here or post up on the True North Toyota Land Cruisers forum for recommendations on any local injection shops. Louis and Brian both have diesels here in town and I know there are others too. Someone might know of a good local place.

    :cheers:

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