D24T Injectors in D24 NA

[DieselScout]

Is there any benefit (HP, MPG, etc...) to adding D24T injectors into a D24 NA?
Specifically, a D24 that has a thin MLS HG and a larger bore.

[ngoma]

I can't think of any. IIRC, the "T" injectors are set to a higher POP, not sure if the nozzles are any different. Remember, it is the IP that sends the measured fuel spurt to the injector, so a different injector can't really inject any more fuel into a combustion chamber than what it receives from the IP.

Of more importance is that the injectors are:

• All set to the correct POP, and not widely varying from each other.
• Good atomized spray pattern
• No drips or moisture when held just under POP for 10 seconds.

[DieselScout]

Is it worth replacing/rebuilding the injectors during an engine rebuild?
Mine appear to work just fine (using small bench pump tester), but all the sprays look the same too me, lol.

I keep seeing Monark nozzles in my research, are they any better than what's in the original injectors?

[ngoma]

Worth replacing only if they are worn or malfunctioning.

Spray pattern should look like a fox tail straight out, not a pee stream or crooked.

I did use Monark GTD style several years ago. It ran fine, hard to tell if there was any performance or economy improvement. Minimal, if any. Had more to do with my careful lapping/testing/setting procedures that they were well balanced.

That was years ago, no telling where the Monarks are manufactured now, or what their quality is.

[DieselScout]

I'll have to look more closely at the spray patterns.
If I do need to replace one of the injectors, is "NA10X" the correct part number?

[ngoma]

What is that number from? Greenbook shows 068 130 205 B, stamped near the middle of the injector body, just above the housing parting threads. Nozzle P/Ns vary, depending on T or N/A, also on markets.

[v8volvo]

I think the NA10X number would be a Bosch number referring to a remanufactured injector (the "X" suffix for a Bosch PN always means reman).

No comment on whether it is the "right" part number for a D24 but as long as they are VW-style nozzles with the correct pop pressure, I cannot imagine there would be any issue? If it works in a Rabbit 1.6L D or TD it will work fine in a Volvo.

FWIW/AFAIK: there is no issue using higher pop pressure turbo-spec injectors in a NA engine. But you don't want to go the other direction and use NA-spec pressures in a turbo motor.

[DieselScout]

The number kept coming up when cross referencing numbers with VW counterparts, such as here: https://www.partsplaceinc.com/vw-1-5...ctor-1423.html (not sure if it's exactly the same, though)

[DieselScout]

I took apart a couple of the injectors and the nozzle part number reads "dnosd1930." I can't find many 1930 nozzles online, but there seem to be plenty of "dnosd193." Will the 193 nozzle work as a direct swap?

Is it OK to just only replace the nozzles or would the springs, shims, etc...also then have to be replaced?

[RedArrow]

You might get away with it (IF it happens to run okay afterwards) but the right way to do it is testing And resetting the injector that you took apart/opened.

There`s not much chance for the settings of the `newly built` injector to randomly* fall to around where they HAVE TO be (= right at factory specs).


Quality reliable testers with the perfectly ideal dial range aren`t cheap
It is also quite challenging (and risky) to keep&maintain the surgically clean environment that rebuilding the injector absolutely* needs.
Add all that cost, time and hassle up and maybe you are at the prices that the reputable reliable PRO service would cost...
If built well, they will be perfectly set and serve you well and reliable for about 50-75000 miles depending on condition of fuel... maybe the tank, filter, injection pump circumstances can also improve or worsen that number, IDK.


I also have a couple of sets that need to get rebuilt and if finding those adjuster shims/washers were much easier then I would possibly have a second attempt at doing it myself... but until then I would prefer sending them to a reputable shop/mechanic who deals with these type of injectors on a daily basis, professionally. Ideas and links are welcome!


Here I would like to (re-)share a link that I got long ago from a forum member. This good article is about all the details around rebuilding the injector.

https://vincewaldon.com/2008/10/29/h...idi-injectors/