HOW A BOUT THIS ONE ...

[panchosteam]

Will a spacer spark plug like bring down engine temperature on our diesels if fited on the injectors? or will the temperature increase? just a silly question.

[trbankii]

If I read between the lines, are you asking if you used a spark plug spacer washer under the injector whether it would increase or decrease temperature?

I'm not exactly sure that it would do either, but it may interfere with the spray pattern getting into the chamber properly.

[panchosteam]

Hi, no not a washer from the spark plug i'm talking about a probably 1" inch or so spacer used on gas engines when the spark plugs get wet with either gas or oil.

[trbankii]

I don't think that I'm familiar with those. I thought you meant like an indexing washer for a spark plug.

That much of a spacer and I would think that it would draw the injector back far enough that instead of spraying into the chamber, it would spray against the sides of the hole and mess up the atomization.

[doncannon]

I think he means the non-foulers people would use if they had problems with gas engines burning oil. they are about an inch thick and screw down in the spark plug hole then your spark plug screws into them.
Don

[panchosteam]

You got it Don,that's what i was talking about,it's only a silly question that came to mind.

[arveetek]

First of all, the anti-fouler devices have a small hole on the end, to keep oil from splashing up on the spark plug. This would prevent the injector from spraying the fuel right, causing it to drip the fuel, causing severe piston damage, knocking, timing issues, etc.

Second, the injector body threads are nearly twice the size of any spark plug I'm familiar with. You pull the injector out, and you've got a big hole there. I doubt any anti-plug fouler would fit.

Third, the injector sprays fuel onto the glow plug. The anti-plug fouler would probably be touching the glow plug, or damage it in some fashion.

Fourth, there isn't much room in the precombustion chamber where the injector resides.

In some respects, the indirect-injection systems on our diesels acts like the anti-plug foulers do. The injector and glow plug screws into a precombustion chamber. The piston forces air up into the pre-chamber, where the fuel is squirted and the heat from compression ignites it. This is then all forced out a rather small hole in the pre-chamber towards the piston. The injector does not spray fuel directly onto the piston.

Casey

[doncannon]

arveetek,
I agree with you. you made a lot of good points! Do you know if we can convert indirect injection over to direct? thank you, Don

[trbankii]

There is a way to convert to direct injection - swap in a Cummins...

Seriously, ID vs DI is an engine design thing. Not something that can be changed on a particular engine.

[BobND]

Originally posted by trbankii:

Seriously, ID vs DI is an engine design thing. Not something that can be changed on a particular engine. That statement is true for these light-duty GM diesels, but not universally true.

Caterpillar, (and likely others) made engines that could be DI or IDI within the same basic family by switching cylinder heads (and probably pistons).

[G. Gearloose]

Let the true gas converted engine stand up...
Uhm..didn't the Navistar 6.9/7.3 jump from 446 gas to 6.9 IDI to 7.3 IDI to 7.3 DI to...

[NH2112]

I think the 6.9l's precursor was the 404 gasser, and the 446 was converted into the 7.3l. I don't know whether it was the bore or stroke that the gassers shared, but the 6.9l seemed to have a slightly better reputation for reliability, possibly due to thicker cylinder walls.