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goodguyneighbor 04-21-2019 04:59 PM

Engine won't start, did the wiring harness disabled my bus?
Hi All!

So I've been slowly skinning the inside of my bus and started on the ceiling work. I disconnected some wiring harnesses, as well as all the lighting, emergency exits, etc. I also removed the heat exchangers.

At one point I realized that the engine wouldn't even turn over. I reconnected some wires towards the emergency exit and it would turn over again, though I never tried to actually start it.

Unfortunately, now, all it will do is turn over, it won't start. I am wondering if there is anything relating to having all the wiring harnesses properly connected that is preventing it from starting properly. I know the interlock will prevent the ignition from firing, but my ignition is firing fine.

The bus has always started fine, the last time I drove it was probably two weeks ago, and it is always fired right up. The only deltas between then and now are the removal of the heat exchangers and the disconnection (and possible improper reconnection of the wiring harnesses to the emergency exits, windows, lighting, fan, and rear door.

The battery is fine, the bus has gas, it turns over, it's 70 degrees outside. I'm kind of lost as to whether this may be a larger issue, and unfortunately I am new to the diesel mechanic thing. I am exploring whether it is a fuel/pump issue right now, I've been priming it, but I haven't been bleeding it, going to try that next but if this is some random wiring thing, I may be spinning my wheels for a while, Any ideas?

goodguyneighbor 04-21-2019 05:16 PM

pressed the primer 20-30 times, fuel (and no air) readily comes out when I press in the schrader bleeder valve. Still won't even pretend to start.

Eclipse436 04-24-2019 07:24 AM

Have you checked your coolant level after removing the heaters? Some buses won't start if coolant level is too low.

WARGEAR 04-24-2019 01:32 PM

What bus/engine?
My bus sat for 6 months, I fired it up for the first time since and it started up right away. All these diesels need is fuel, air, compression. I’m going to assume you have air and compression so the issue must be no fuel in the cylinders. Fuel on newer engines is electronically controlled now with solenoids and valves so I would start at anything that inhibits fuel flow into the cylinders. Try reversing those exit window connections. Could be one is backwards. Let us know how it goes!

goodguyneighbor 04-25-2019 09:20 PM

I have virtually the same bus as you WARGEAR (you can see my info under my user name) which is cool!

After some extensive googling, I ended up cleaning the debris filter below the primer pump, that didn't work but as it was filled with crap, it pointed to the fuel filter likely being filled with crap as well.

I changed the fuel filter, primed it a few times and she fired right up!! Yay.

I still have chokey power issues on hill climbs that I was hoping would get resolved by this, but I now suspect the issue is with the injectors, though I was thinking I would throw some of that Royal Purple Max Clean stuff in and see if it would clean out the fuel system a little, it was obviously a bit cruddy in there.

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