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lapeer20m 05-28-2014 02:38 PM

Help! Can't get 5.9 cummins to start
We just installed a wvo system into a bluebird tc2k with Cummings 5.9.

After conversion, bus started on diesel and ran great for about 10 minutes at a high idle, then it abruptly shut off.

My guess is that it is a fuel delivery problem.

Engine cranks fast. Jumper cables were connected before we even attempted to get it started.
Diesel filter is full.
Injectors are cracked with little to no fuel coming out
We double checked the routing of the fuel lines
Installed an electric fuel pump near the diesel tank
Checked to make sure fuel is being returned to the diesel tank
Primed the wvo side of the system
Checked to make sure the electric fuel shutoff solenoid in the side if the injector pump is working
Put 10 gallons of diesel fuel into the tank to make sure it wasn't low

Fuel is definitely circulating through the lift pump, filter, into the injector pump and returning to the tank.

Why won't it start?

Engine has under 100k miles on it and ran great a few hours before.

I'm wondering if the fuel shutoff solenoid is not moving far enough? But I find it unlikely that the bus happened to suffer a mechanical problem at the exact same time we were working in the fuel system.

bansil 05-30-2014 11:49 AM

Re: Help! Can't get 5.9 cummins to start
Mine had an electric solinoid that controlled fuel shutoff, the wire actually broke the same day I did fuel filters....go figure

Make sure the solinoid pulls the cutoff lever and HOLDS it, there are several YouTube and wire diagrams that describe this

Mine was clicking solinoid while cranking, but wasn't holding open during crank due to the 2nd solinoid not working

nat_ster 05-30-2014 03:19 PM

Re: Help! Can't get 5.9 cummins to start
Mine are controlled by a push pull cable. You should be able to move it by hand.

Good luck, keep us posted.


sdwarf36 05-30-2014 06:54 PM

Re: Help! Can't get 5.9 cummins to start
Can you give some more info on the 10 minutes of running time?
Was any one the time on veg? Did it start right up? 10 minutes is a long time-do you think it could run on the filter that long?
I would suggest putting some clear fuel line in temp. to be able to see whats happening.
Long start ups after a conversion are fairly normal-but not running 10 minutes + dying.

White99z 05-30-2014 07:19 PM

Re: Help! Can't get 5.9 cummins to start
The bus he is talking about is my bus. We ran it after the conversion after cracking injectors and bleeding. We accidentally left the veggie filter off while run in on diesel and didn't realize diesel was making its way back down the line to this filter and literally pouring out. The consensus is, we ran out of gas. What has ensued was three days of attempting to bleed and purge air to no avail...

Getting towed home tonight and I will look a it early next week.

SmokinJ 07-31-2014 09:28 AM

Re: Help! Can't get 5.9 cummins to start
Any update on the no start issue?

White99z 07-31-2014 02:02 PM

Re: Help! Can't get 5.9 cummins to start
Yeah... sorry! I posted on the build thread and didn't post here. Here's the copy and pasted text from my build thread.

News on the injection pump:

The bus is currently in the shop and the pump is being rebuilt tomorrow. On Friday, the local Bosch shop discovered the cause of the locked up fuel rack. At some point when we were running the bus, a small metal shard worked its way loose from the metal tubing that was cut improperly (yes... it was our fault :shock: ). The bad cut was on the clean side of the fuel filter (after the filter) and it went into the injection pump and scored one of the plungers in the Injection pump very badly. This caused the plunger to get stuck and subsequently, the fuel rack too. With the fuel rack hung up, the delivery valves were not opening and no fuel was getting through the lines to the injectors. Total cost... just over $2000 :shock: :shock: :shock: It really sucks... especially because it was, in essence, a mistake in the conversion process. A hard lesson learned but if I want to look at it optimistically, I now have a VERY intimate knowledge of the entire fuel system and feel that I could diagnose and repair any fuel related issue short of rebuilding the injection pump. This is good knowledge to have for a touring bus running on veggie oil. The pump will be in the bus by the end of the week (it has to go back to a different shop that pulled the pump) and then, after it is running good, it will go to yet another shop to repair the rear hub seal leak and replace the bearings. We will pick it up next week when we get home from a music festival that I am playing at. We are happy to be moving forward, but have our heads hanging a little low this week :(

SmokinJ 08-02-2014 07:36 AM

Re: Help! Can't get 5.9 cummins to start
It seems that knowledge is seldom cheap.....
But that will be great knowledge to have no matter what you are driving!
My first bus, I was in florida on a 2 lane road stopped for a flag man at a construction site. I sat waiting for the man to wave me into the next lane to pass the site, as soon as he does, I start pulling into the next lane and the bus just died..... Now I'm taking up both lanes as well. Eventually they brought over a big yellow grader and pulled me off to the side so other could pass.
The problem ended up being the fuel gauge was stuck on full and I ran out of fuel. I luckily had a 2nd tank, I flipped the switch over to the second tank and had a friend on the phone telling me how to prime it to get it going.....

crazycal 08-12-2014 03:23 AM

Re: Help! Can't get 5.9 cummins to start
Bummer, that was an expensive lesson. :cry:

roach711 08-12-2014 08:16 PM

Re: Help! Can't get 5.9 cummins to start
Experience Gained is equal to Equipment Ruined. :(

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