SOLVED !! Stranded 93' MCI 12 6v92 DDEC3 Wont Start

Beachfinn · May 14, 2016, 04:59:03 PM

Good evening,
i am now stranded in Longview TX. Dropped the buss off two days ago to a fabricator to build and bolt on a hitch. Went to pick it up today and it will not start. They moved it on the yard yesterday, but not even a promise today. Is there anything they could have done, ie flipped things in wrong order? They did leave the chime lights on, but it seemed to crank just fine till i just about killed the battery. Here are the details:
- Reliabilt 03' 6V92 engine
- Single fuel filter with a clear cover, about 1" of fuel visible on the bottom.
- Engine turns and with small squirt of magical "E" runs for few seconds.
- Im sure there is a emergency shut off of sorts, but it isn't a flap or anything that i can see on the air side, is there a fuel shut off and where might that be?
- Maybe somehow lost prime? Any easy way to prime or check?

Id love to get it running by myself and not call Steward and Stevenson, but, at least they are in town...

robertglines1 · May 14, 2016, 05:04:12 PM

maybe someone siphoned the fuel. Or shut the 12 V switch to ddec off.

Geoff · May 14, 2016, 05:05:27 PM

Humm. Did they weld on the chassis without putting the ground as close to the area to be welded? Or not disconnect the grounds to the ECM?

--Geoff

lvmci · May 14, 2016, 05:41:10 PM

Hi Beachfinn, is there an emergency sto, shutdown engine switch on the dash? Mechanics that don't work on buses, flip switches when trying to start them up, if they don't know what their doing, happened to me once. Someone here will tell you the procedure to rest the flap , if you have one, lvmci

ArtGill · May 14, 2016, 05:53:39 PM

If there is only one inch of fuel in the filter and it runs on either, fuel is not getting to the engine. The fuel filter should be full
Art

Beachfinn · May 14, 2016, 06:10:12 PM

maybe someone siphoned the fuel. Or shut the 12 V switch to ddec off.
- the fuel gauge still reads 3/4 full, theres a pad lock on the fuel bay door, so that should be ok. 12v switch to DDEC, first im hearing of it....

Did they weld on the chassis without putting the ground as close to the area to be welded?
- there should have not been, and they say they did not weld anything on the bus.

is there an emergency sto, shutdown engine switch on the dash?
- i have not found an emergency stop on this bus. I don't think it exists on DDEC3?

If there is only one inch of fuel in the filter and it runs on either, fuel is not getting to the engine. The fuel filter should be full
- and i think this is correct, i recall always observing it with just a slight air space at very top. Should the top just screw off and manually fill? the filters were changed by Darby Diesel about month ago...

scott332 · May 14, 2016, 07:05:45 PM

The fuel filter sounds like it is a Davco type, which should not have fuel to the top. As the filter gets dirty, the fuel level rises. Once the fuel level gets too the top inch, its time too change the filter.

Have you checked the fuses in the battery compartment? It's a long shot, but I once blew one of those fuses on the left side of the battery compartment, they control the DDEC computer. The bus would not fire since the computer didn't have power.

There it's no air box flapper on a DDEC engine, those are only on mechanical engines.

They might have flipped one of the rear control switches as the left side of the engine. One switch should be on "run", the other should be on "front" if you are trying to start from the front switch.

Beachfinn · May 14, 2016, 07:16:21 PM

The rear switches should be fine, I was starting it from the rear.
I'll check the fuses, I'll have to get a small shreader valve compressor to air up, as all my tools are in the belly. Lesson one; hook up compressor to air up from the genset power. Honestly, it could be worse, I don't have to be anywhere, might as well learn DD, I have few days to spare...

scott332 · May 14, 2016, 07:29:22 PM

Yes, those pesky air operated baggage door locks. A good idea for buses that are always running, but in my situation, being parked for long periods of time I removed them.

thomasinnv · May 14, 2016, 07:59:42 PM

Quote from: scott332 on May 14, 2016, 07:29:22 PM
Yes, those pesky air operated baggage door locks. A good idea for buses that are always running, but in my situation, being parked for long periods of time I removed them.

That was one of the first things to go bye-bye on mine.

lvmci · May 14, 2016, 09:44:36 PM

Yes, air lock baggage doors, not good if engine not running, lvmci...

gumpy · May 15, 2016, 04:46:16 AM

If it's a FuelPro filter unit, it's not supposed to be full, so it's probably not a fuel issue.

Sounds like maybe they welded on the chassis and fried the DDEC.

I like my bay door air locks. I made some clips that I can install over the ends of the cylinders to keep them from locking automatically. Simple and effective.
I installed a small air pump and connected it into the air locks so I can unlock them when the bus has no air.

blue_goose · May 15, 2016, 05:03:57 AM

Check to see if the stop engine and check engine lights come on when you turn the switch on. If they are not coming on you don't have any power to the ecm.
Jack

DoubleEagle · May 15, 2016, 06:12:09 AM

Check the position of the fuel shut-off lever that is controlled by the skinner valve (assuming the DDEC3 version has this setup). It might be hung up and not releasing the shut-off position. As the others have mentioned, if you have the single fuel processor and the filter is fairly new, the visible level will be low, but if you know that the level was higher recently, then something changed. It would not hurt to add fuel through the top in case you lost prime for some reason. The filter will find its correct level after it is running.

luvrbus · May 15, 2016, 06:24:13 AM

As mention if the check engine lite doesn't come on you have no power to the ECM start there then we can help you,
It's probably a ground if they tied your trailer plug into grounding stud for the ECM or even low on coolant