direct vs indirect injection

[David USMC]

Ive considered the Deere 4000 series vs the Kubota B series. In the larger Deeres 4200 and above they feature direct injection vs indirect injection. Does anyone have a bias towards a particular engine, and if so could they give me their reasoning in this matter. Thanks in advance.

 

[MChalkley]

My bias is toward the system touted by the last manufacturer brochure I've read. /w3tcompact/icons/wink.gif

Seriously, though, every manufacturer says theirs is the best and they all seem to work well. Direct injection should theoretically be more efficient, so I generally prefer it, but there are supposedly ways to compensate for this with various forms of indirect injection, though I think these generally involve computer control. Indirect injection engines are usually quieter, unless computer control is used on the direct injection engine to compensate for that. (I like the sound of direct injection, personally.) And so it goes ad infitum, ad nauseum. Generally speaking, though, direct injection is considered best for getting the most bang for your buck, pardon the pun. If you live in an extremely cold climate, indirect injection engines can sometimes be easier to start, but I think this advantage has been minimized by the usage of extremely "hot" glow plugs.

Still, all in all, you might be better off using other criteria to make your decision. Like what you favorite color is, etc... /w3tcompact/icons/smile.gif

Mark

 

[_RaT_]

Is that true Mr Chalkey, I've always been under the impression that direct injection was easier to start in cold weather, glow plugs or not. Both the Ford (Powerstroke) and Cummins diesels are direct injection. I'm not convinced that either is always better, but tend to lean towards DI. This is complicated by Kubota however who builds both types for their current models. The indirect injected on the 4310 and smaller are very nice, the direct ninjection I have on a Kubota L4850, a 5 cylinder diesel is probably the finest diesel I have ever used, and that includes, yes, dare I say a Caterpillar powered piece of equipment. Arguably some say that the indirect injectors should laast longer then direct injection because of the temperature extremes encountered by direct injection nozzles, but having been to a local Standyne/Bosch injection pump rebuilder, they say they see no increase in direct injection injectors being replaced. Go figure.

 

[Billc]

I clicked on to this thread hoping beyond hope that Paul had made another "direct vs indirect" post. Disappointment is heavy.

Mr. Paddock, you may want to look at a lot of posts on this subjest that were done about 10 days or so ago. Pay particular attention to one of the ones made by PaulB. It sort of explains "direct vs indirect" better than I've seen anywhere else. I'll take the liberty in say that Mr. Chalkey thinks the same!

 

[MChalkley]

Billc, I thought about referring Sir King Rat to those posts, but decided they were more technical than what he was looking for. /w3tcompact/icons/wink.gif Well, we'll see.

Sir King Rat, the theory I've read (but I haven't read this week's bulletin yet) is that the glow plugs can more easily heat up the small precombustion chamber used in indirect ignition so that it can then ignite the main cylinder.

Have the Navistar diesels used in Fords always been direct injection? I thought sure they were indirect, or used to be.

Mark

 

[PaulB]

Bill - having in one thread been accused of both adultery ("Paul, so exactly how well do you know my wife"), and Murder One ("Paul, you kill me!"), I figured it is best to lay low for a while.

 

[_RaT_]

Yes Mark, the older non (Power Strokes) Navistar diesels are indirect injected. Have 8 glow plugs that stay on for durations dependendent on the temperature. Rat...

 

[_RaT_]

Mr Billc, those wouldn't by chance be the ones that got over my head so quickly that I had to move on. I recall a post by , hmmm, was it Mr Paul Bookbinder, regarding his multifaceted diesel that was both direct (DI) and indirect injection (IDI)? Theres a name for that, its called redirected injection (RDI). As I recall it involved directly pouring diesel into the tank while indirectly getting some on the floor. Thats when I knew it was over my head. Ya gotta keep it simple or I lose interest fast. Rat...