Injectors and smokey startups - Related????

[Chaz]

Hey Guys,
 A little history:

As some of you know, Dallas rebuilt my 8v71 a couple years ago. We did not put injectors in at that time as we didn't know if it needed them.
When the rebuild was done, my bus would smoke about a grand total of 3 seconds. We started and stopped it a few times and I was tickled pink. Then on the first trip, I went a little over 200 miles, shut it off for a couple days and when I tried to start it, it grenaded a cylinder!! (liner, piston rod, etc.) Don't know why, but that is water under the bridge, I guess.
Dallas and Kat drove out to it and replaced the destroyed stuff and I was back on the road. I've driven it maybe 2000 miles since.
But after that, everytime I start it, she smokes like a fright train till I get it on the street. Seems like it needs to get warm or something. Then she runs pretty good (but then, what do I know? This is the ONLY diesel I've ever driven whatsoever!!  )
I told Dallas at the time and he said that the injector in that cylinder may have gotten "tipped" just enough to cause that and yet still run OK.

What do you almighty Guru's of the diesel world think??   Could that be the case??
Also, could injectors cause it to smoke only till it gets out on the street then clear up???
I have a buddy who has worked on bus's (TANK -Transit Authority of Northern Kentucky) for many years and said he would replace then for me and run the rack if I got the injectors. He use to do a lot of that in his earlier days. He does a lot of work on the bus's themselves but isn't sure if injectors would be the problem solver. Hence, I throw myself on your mercy.  

Any ideas, help, signs to look for, etc.,  would be GREATLY appreciated.   ANYTHING!!

I did just get back from a Metal Meet yesterday(400+ mile round trip) with the 'ol girl and she ran good. Sometimes it feels like it has more power than others but, like I say, I am pretty much a rookie at driving diesels. They sure aren't like my small block Chevy's!!   lol

Thanx a bunch!!!!!!
  Chaz

[Ed Hackenbruch]

Chaz, do you have a block heater? If so try plugging it in for 2-3 hours before you fire up next time. Somewhere i remember somebody saying that it takes a few minutes of running for the rings/pistons to completely seal? Also if you start it a time or two while working on it and don't drive it you may have unburned fuel left in the cylinders and it will show up when you first take off. This might help narrow it down a bit.

[eddiepotts]

Do you think they may have cracked the oil ring installing the piston?

[Ncbob]

If the smoke is white it's unburnt fuel...and possibly could be a dribbling tip or check valve in an injector.

If the smoke is blue it would indicate some accumulated lube oil in a cylinder(s).

Did Dallas run the whole rack after replacing the faulty Piston, etc or at least the rack on that bank? Too you don't mention what the Ambient temperatures are when you start this engine. Anything below 50 Deg. and they'd prefer that you use a block heater.

FWIW,

NCbob

[luvrbus]

Chaz, the 2000 miles is the problem it takes around 10,000 up to 20,000 miles for the rings to seat on a rebuilt 2 stroker a bad injector is white smoke on start up and black smoke after warm up


good luck

[Chaz]

Thanx Guys.

Ed, Lately the temp at which I have been starting has been over 70*. But this has been happening for 2 years now. It's not anything a heater could solve. She does start very well, I will say that.

Eddie, Not sure how to tell if a ring is cracked. I know DD are a little different in that you can see in the cylinders somehow. I don't know if there would be any tell-tale signs to be seen that way or not.

Bob, the smoke is white. That kinda made me a little on the concerned side as I was hoping and praying it wasn't coolant....... that was mentioned to me. In a small block, that would most likely be the case. And like I said, I really don't know anything of consequence about these motors. This is the first one I even so much as touched! 
I'm not sure what Dallas did after the repair as I was not there. I came back home and he stayed with the bus (about a month or so I believe) to get it done. But as I mentioned earlier, this would even happen when it was 90*+ outside. It doesn't seem to matter. I did also run it last December with the same results. She started wonderful and I must admit, I didn't use my heater. Bad thing??   

Luvr, understand the break-in period and would have accepted it except for that it didn't smoke at all in the beginning. Would that be normal? And I gotta tell ya........ MAN she smokes!!!!! Mosquito's and neighbors are not really happy with me.    I feel kinda bad about it. (except for the skeeters! )
And I don't really see any black smoke per se when she is warmed up. Is it possible that it just needs the rack run again??

Sorry I keep beating up this issue but I'm figuring it will be kinda pricey to put injectors in her. And I don't want to just go throwing parts at her till I figure it out.

And, if I should happen to need injectors, where would you suggest getting them?? I understand rebuilt ones are good too. I think my motor has "brown" ones in it?? Dallas mentioned a California injector and others. What is the best ones to use??

Thanx again guys! This could be a big money saving thread for me, so I REEEEEEALLY appreciate the help!!

All the best,
   Chaz

[robertglines1]

Chaz cheap ck..make sure air box drains are blowing air at a idle..should till 900rpm or so then should shut and air box would go out thru intake ports into piston area then exhaust..If blocked it would accumulate when shut off or idle and be burned till it depleted accumulation .the drains need to be open .when off and up to about 900rpm..you can take them apart and clean just take note of how you took apart or do one at a time..Bob

[Ncbob]

Chaz, Bob is right on. If the engine can't breathe properly it will act funny and make white smoke. If it clears up after a few minutes of running it has probably cleared the unburned fuel out of the cylinder(s).

Bless his heart, Uncle Ned has a 6V92 that, on startup, has been responsible for killing more mosquitoes than the states of NC, SC and FL combined. But when he's ready to hit the road it runs like a bootlegger with new tires! 

NCbob

[Rick 74 MC-8]

Chas

       I lost an injector in TX a few years ago. When I got home the guy a DD told me how what he called short it out. If you remove the valve covers and start the engine. With a real big screw driver, kinda wedge in in as-to hold the injector from returning up and reloading with fuel. That cyc wont fire.  Repeat to each cyl. You may find  which cyc is the culprit. I'm sure someone hear can explain this better than me as it took me over 10 min to type this brief explanation


                                                                                       Rick 74 MC-8 8v71 na

[TomC]

Chaz-I would pull all 8 of your injectors and have them pop tested (not terribly hard with the V drive).  Then you'll know for sure.  If it still smokes when started with all injectors in good shape, then you have a piston/ring problem.  Your engine should only smoke for a few seconds and clear up at idle.  Good Luck, TomC