14B-T, 15B-T, 1HD-T Injection nozzles etc. - cleaning or replacement?

[Eurasiaoverland]

I took my injectors to a diesel specialist on Saturday and was a bit surprised when 3 out of 4 of them came back bad. They are 5 port injectors and should crack at 200-210 Bar. But three out of four spurted out two or three streams of diesel at about 160 Bar. They are nozzles from a 15B-T Mega Cruiser engine and are not available new.

The people at the shop said the nozzles need replacing, but I suspect they may just be gummed up from being in an engine which has been standing for many years (I think maybe ten or more).

How does one tell when an injector nozzle is too far gone to be cleaned and put back into service?

Does anyone have a resource where I can compare injector nozzle specs (e.g. no. of ports, port angle etc.)?

Does anyone know how many ports a 1HD-T injector nozzle has?

Thanks

EO

 

[lacalvette]

That's infortunate ;( usually diesel do not gummed like gasoline. Hi pessure nozzle have very small hole on the tip, not recommended to try cleaning with wire brush etc. Maybe ultrasonic? Mating surface on the nozzle are perfectly machined, hard to rectify.
Normally when they fail test, the nozzle are tossed in the bin.
I Would suspect that nozzle hole number and angle are important for a specific engine, knowing these data could help you finding substitut. others japanese engine may have similar nozzle?
i wish you good luck
Justin

 

[1HaytchZed]

The labor time and cost to clean each injector isn’t cost effective. A denso nozzle should be $50-60. I’m assuming similar cost as a 1hd-t injector nozzle.

 

[Eurasiaoverland]

That's infortunate ;( usually diesel do not gummed like gasoline. Hi pessure nozzle have very small hole on the tip, not recommended to try cleaning with wire brush etc. Maybe ultrasonic? Mating surface on the nozzle are perfectly machined, hard to rectify.
Normally when they fail test, the nozzle are tossed in the bin.
I Would suspect that nozzle hole number and angle are important for a specific engine, knowing these data could help you finding substitut. others japanese engine may have similar nozzle?
i wish you good luck
Justin

Thanks Justin, sorry for my slow reply. Yes, that makes sense. I will keep the original nozzles and will try ultrasonic cleaning in future, but will get some new nozzles.

I'm just a bit puzzled about what caused the clogging on my injectors since I believe the engine has less than 100,000 km and it was used in Japan only (and I assume only by the ared forces), where I don't imagine there is a problem with bad fuel. Perhaps the engine spent a lot of time idling. Or maybe they somehow deteriorated in the years that the engine was put in storage.

I can get a set of 14B-T nozzles which have the correct crack pressure and I believe also have 5 ports. My engine uses a 14B-T head so the nozzle angle/protrusion should be identical. Luckily they are still available but are expensive at about USD130 per nozzle.

The alternative would be a 15B-FT nozzle, but these have a lower crack pressure (180-190 bar vs. 200-210 bar) and as the head is a 16 valve design, as opposed to my eight valve head, I think the 15B-FT injector is vertical compared to the inclined orientation of a 14B-T/15B-T injector.

I think a 1HD-T nozzle may not be suitable, as the injection volume per cylinder on a 15B-T would be significanly higher (4 cylinder 4.1 litre engine vs. 6 cylinder 4.2 litre engine).

Thanks

 

[TheBussman]

this thread has a link to a useful page "toyota nozzles" that could give you leads on a possible replacement. looks like 15b-ft or even 15b-fte should work fine. 1hd-t is also close.

 

[Eurasiaoverland]

this thread has a link to a useful page "toyota nozzles" that could give you leads on a possible replacement. looks like 15b-ft or even 15b-fte should work fine. 1hd-t is also close.

Thanks, that is indeed a very interesting thread. The pre-common rail direct injection engines use DLLA type Denso nozzles; for the 13/14/15B and 1HD platforms they are DLLA150P type. Thinking about similarities and differences in engines I considered the following:

-1HD-T nozzles are for a six cylinder engine with a very similar capacity to my 15B-T, so on a per-cylinder basis I would expect slightly lower injection volumes.
-11B/13B/14B non-turbo nozzles seem to have four ports rather than five in the 14B-T and 15B-T.
-15B-FT, 1HD-FT nozzles are for two-stage injectors with a lower crack pressure. The nozzles also come into the engine vertically as opposed two the eight/12 valve engines.

So that leaves the 14B-T and 15B-T. The 15B-T nozzles, DLLA150P622 are no longer available.
The Toyota 14B-T nozzles are available (from Denso, not Toyota) but are expensive. However, I found that there are different Daihatsu 14B-T nozzles which I don't think are available from Daihatsu but are available from Yamaha, who used them in the marinised 14B-T, the ME370. That engine came intercooled and has a rated output of 165HP (cf. 140HP for the Toyota 14B-T) and the nozzles are still available. That output is probably about what my 15B-T produces, so this seems potentially a better match. I ordered a set from Japan for less then half the price of the Toyota/Denso 14B-T nozzles and found that they have been superseded to yet another nozzle, so let's see what turns up...

 

[TheBussman]

Most of the time the marine injectors for the diesels I've been around are larger and are a little louder/ smokey at idle. you'll have to see what the nozzle number is I'm guessing it will be higher then a DLLA150. may have to turn down your idle a bit.

 

[Eurasiaoverland]

Most of the time the marine injectors for the diesels I've been around are larger and are a little louder/ smokey at idle. you'll have to see what the nozzle number is I'm guessing it will be higher then a DLLA150. may have to turn down your idle a bit.

Surely smoke at idle is down to injection timing and the fuel map of the pump? I'm not running any other Yamaha parts.

The pre-superseded nozzles for the Yamaha ME370 were the same as the Daihatsu 14B-T: DLLA150P621. I'm interested to see what the superseded nozzles are.