injector and rocker arm questions

[K5dreamer]

Quick one - while searching the forums on my injector question, i stumbled across a bit of info i was unaware of. early 6.2's used cast rocker arms, and 86 and newer used stamped.... is there a benifit to the cast ones? if so, are they a direct swap for the stamped ones on my engine?

Ok, injector question. My M1009 dosnt have that many miles on it, only about 70-75k, but it is 23 years old, and has probably spent alot of that time idling, so ive decided its time for some preventative maintanence (before i burn a hole in a piston or something), and im debating having the IP and injectors rebuilt. regarding the injectors, i know alot of VW and Mercedes guys install modern updated nozzles with more holes, and better spray patterns for both more power and better fuel economy. usually this also means less black smoke and smoother, quieter running. Anyone here do this, and have a specific nozzle size or part number they reccomend? maybe using marine, or 6.5L nozzles? or some other random bosch part number?

 

[Russell]

Can't help much with the injectors, but stick with your stamped rockers. They do have the plastic retainers that are prone to fail, but the old cast rockers tend not to oil properly and prematurely wear out.

 

[K5dreamer]

thank you sir, good to know

with the plastic retainers.... are those spring retainers? or rocker arm retainers? and is there a more reliable replacement?

 

[tRustyK5]

I wouldn't get too worried with injectors and spray pattern the way you are. The 6.2 sprays the fuel into the pre-cup, not directly over the piston.

Rene

 

[Russell]

The little plastic retainers hold the rockers in position, if they break, the rocker will float in either direction causing damage to the pushrod, valve tip etc. Best I know there is no alternative to them, but that they are still available from the dealer brand new.

 

[K5dreamer]

hmmm.... cuz i know the older vw engines were IDI, and the mercedes guys are running IDI engines, and both say that nozzle upgrades make a difference. figured it was worth a shot on our rigs too. although i do completely agree that nozzle and spray pattern are far more critical and effective an upgrade on direct injected systems.

as for thsoe little plastic retainers...... man, now i wanna pull my valve covers to give em all a good inspection, im guessing if there are any problems they are pretty obvious???

 

[Russell]

Either they are doing their job or they are broken -- no real grey area there!

As far as the nozzles go, I think that I'd leave them be unless you are noticing a bunch of smoke (aka unburned diesel) at idle that goes away with some throttle. Only way you are gonna burn a hole through your piston is if you are overfuelling under load, which you'll be able to notice with the presence of black smoke. Overfuelling, or incomplete combustion due to dribbly nozzles appears as a eye burning bluish / grey smoke at idle.

 

[K5dreamer]

yeah im just a paranoid fracker, ive got an exhaust leak on the passenger side header that always makes me think ive got a loose rocker arm or a tapping valve or something.

as to the nozzles, i dunno, the trucks just got 23 years on it now, and there is a bit of smoke at startup, cant tell if its white or bluish gray, and I do have some soot issues down the side of the truck due to side exit exhaust pipes. an reving the truck in park i get some black smoke. which honestly is kinda a new thing..... The truck actually runs pretty good, but like i said, im just a fan of knowing. I might just have the injectors tested, cost less than $100 and good piece of mind. And if i have a good month, i might have the pump rebuild and adjusted properly just to know when it was last done.