Need Serious Advice, reached crossroads with bus

[Dakell12]

Hi Everyone, I have been writing on this board for about 3 months now, converting a 1985 96a3 with a 8v92 to a tour bus for musicians. I have dumped close to 45 grand into the project, 8 of which involved a new transmission, as well as fuel injectors to clear up black smoke. My heart is poured into the interior of this bus, and it looks great, but the engine is (now) obviously a dud. It has very little power  (tested out at 240 hp) and I paid 1800 dollars to fix the tons of black smoke that was pouring out the exhaust by replacing the fuel injectors. This fixed the problem for about 1500 miles, and now I am dumping black smoke again. I need advice! Here is what I am looking to find out....
   1) as long as this engine is a P.O.S., can I drive it another 5000 miles to finish up this tour? Is this black smoke going to get worse and strand us?
   2) Should I ask the person I bought it from to replace it in good faith? (He ran a small shop and he had an extra 6v92 around when i was there)
   3) If it comes to it, should I bite the bullet and buy a new (rebuilt) engine, or scrap the plan and sell my beautiful conversion because it will contiinue to suck money?
   4) Where can I look into purchasing a rebuilt 8v92 or similar engine?

Thanks everyone, it means a lot. Have a nice day.

[H3Jim]

Hmmm, no easy answers here.  Maybe get an experienced 2 stroke DD  mechanic to look at it.  It's possible that there is something short of a rebuild that's causing the smoke. 

Running a bad engine does nothing to help it, although you  might be willng to get away with it if you keep the RPM's lower.  But are you willing to risk having it fail completely while on the road and in the middle of a playing schedule, and far from friends and known good mechanics?  Whatever it is is likely to be made worse by running it, 5000 miles is a good distance.

I think if it were mine, I'd seek some good mechanical advice and get a good bid to fix.  Aer you near Luke's shop on the east coast?  maybe you can drivie it, limp it n in there for a fix.

Lastly, if it were mine, I would probably continue to fix it.  maybe you did buy the worng bus, but after the trannyand everything else you've done, now its "only" the engine left.  They are less expensive than a series 60 and B500 to rebuild.  I would keep the 8v and repair it rather than putting in an unknown and lesser 6v.

Keep us posted on what you decide

[edroelle]

My 2 cents.

If you like the bus, keep it.

Like others have suggested, a more thorough analysis may identify what the problem is with your current engine.

If you drive alot of miles, consider a rebuilt engine.  Possibly Diesel Exchange.

If you like to gamble, or are short on funds, find a good used 8V92T.  Possibly NIMCO Bus, or a salvage yard in Canton, Ohio - the name escapes me - but others may remember.

Ed Roelle
Flint, MI

[white-eagle]

there was a perfectly good 1990 Eagle model 15 on ebay 2 weeks ago with a well cared for 8v92t and 740 tranny.  only 10k and he didn't sell it.  you might just be able to buy the Eagle, use the engine and part out the rest to get some money back.  He told me he was going to part it out if he didn't sell it.  you could drive it back to your place, change engines, and drive off. maybe.

the bus was in texas and the number was listed on the listing under carolyn55 or something like that.

[Don4107]

Good advice to have it checked out by a good mechanic.  Has the oil consumption increased?   One of the least expensive, most informative things you can do, is an oil analysis to see what is going on.  It will tell you if the engine is self destructing or if the oil has to much fuel in it.  Could be that the injectors you put in are bad.

Good luck

[Buffalo SpaceShip]

Black smoke is simply too much fuel and/or too little air. I'm assuming you replaced the air filter you posted about previously. Also, what size injectors were put in? Does it have a boost gauge? The wastegate setting could be wrong and/or restricted. Also, the governor or rack could be messed up. What coolant temps are you running? 240hp at the wheels is not that bad, considering you have some fuel/air issues.

As others have suggested, although it's frustrating, don't go write off the engine as a P.O.S. before doing more due diligence. But if you do continue to drive it with black smoke issues, you'll eventually overheat it and it will be a boat anchor.

Get it to a qualified 2-stroke shop... or dig out the DD manual and start learning about it yourself, and you'll get answers instead of speculation and frustration.

HTH,
Brian B.

[Stan]

Brian B gives you good advice. If the engine ran good after the injector change, it doesn't just completely wear out in 1500 miles. Sounds much more like an air problem - air filter or bad turbo.

[Dallas]

Dakell,

I hesitate to ask this, but are you certain this engine is an 8V92?

Does it have a turbo or just a blower?

8V71 and 8V92 Valve covers are the same size and can be interchanged.

If it is an 8V92, rip into the air intake system and make absitively, posilutely sure you are getting the amount of air you need. If it's a repower from an original 8V71 it can't get enough air and will smoke.
Install a restriction gauge to see how much air you really are pulling through it.
Like everyone else has mentioned, the turbo may be incorrect, the waste gate may be improperly set, or it may have some bad injectors or possibly the rack slipped.
Here's a BIG one.... Make sure the exhaust is tightly connected to the hot side of the turbo with NO LEAKS! Exhaust pressure is what drives the turbo and if it isn't getting all the pressure from the exhaust, you won't get an adequate amount of boost, so when you open the rack you'll just be pouring fuel into the engine.

Now, on to my question about being sure it's an 8V92....

If it's an 8V71, you got screwed big time. It will need smaller injectors to run efficiently, The injector timing is different, and the engine timing is different.
But other than a 1" difference in length, the 2 blocks are outwardly identical.

At this point I would not call it a Pile of excrement because from what you've told us, it runs, doesn't knock, isn't overheating, and starts without problem.

Let us know where you are, it's possible that someone on the board maybe able to come and help you with little fuss.

Keep us posted,

Dallas

[Sammy]

Where are you located?
Does it have a turbocharger???- might not have one, only a blower....
Check all hoses and clamps from air filter housing to the top of the blower - get a flashlight and look inside all piping to look for a restriction - rag, dead bird, etc.
Check both sides of the air filter housing - inlet and outlet sides.
There are many more things to check , before you would consider condemning it.
Don't give up yet - find a real tech to check it properly for you - beats throwing money at it for no reason.
Post your answers to the questions that Dallas has asked - this will help some more too.
Good luck.