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View Full Version : Generator - What have I done?



aggies09
10-27-2008, 05:41 PM
I hope this is simple, kinda like my bus' owner. After a brief 4 day trip and everything working fine, I returned home and tried to start my generator from the dash panel and it will not start. I have checked the remote start switch to make sure that it didn't get accidentally turned off and a few other minor checks and find nothing wrong. Can the group give me a few helpful hints of what to look at to see if I can get this to run? Thanks.

jack14r
10-27-2008, 06:07 PM
Liberty has a reset(red button)on the generator watchdog,I would try to reset it.There is also a method to disconnect the watchdog and start the generator without it connected,the coach manual should have the instructions for this.

phorner
10-27-2008, 06:31 PM
Is it possible that the generator start battery is dead?

Does it turn over but fail to start or does simply nothing happen?

Does the light come on for the generator start sequence?

Jon Wehrenberg
10-27-2008, 07:12 PM
Ditto to the above.

Make sure the Watchdog has not tripped, but also make sure you have juice in the battery. There may be enough to engage the start cycle (glo plugs etc.) but not enough to spin it over. Try starting it outside so you can hear what is happening.

dale farley
10-27-2008, 08:02 PM
I know this is probably too obvious, but I am assuming you have at least 1/4 tank of diesel in the bus so the pickup tube for the generator is submerged..

aggies09
10-27-2008, 08:17 PM
Diesel is good. I will check battery if reset does not work. I haven't had any battery problems, but there is always a first. The generator light does not come on when I press and hold the start from the inside panel............headed out to the bus barn.

aggies09
10-27-2008, 08:50 PM
Reset watchdog. That allowed me to remote start as I would have normally. I now realize that the reason the watchdog was tripping out is because the generator will not start. Battery is good. The engine is turning fast enough to start, but it is not starting. Thoughts appreciated.

tdelorme
10-27-2008, 09:35 PM
Tony it's got to be either the fuel filter or fuel pump. See if you can disconnect the fuel line before it goes into the filter and if you get fuel pumping out when you turn the engine over, reconnect it. If no fuel pumps out, the fuel pump is bad. Then disconnect the fuel line after the filter, spin her over and see what happens. If the engine is being turned over by the starter motor at a normal speed and won't start, bet the ranch on a fuel supply problem.

aggies09
10-27-2008, 10:03 PM
Ted, I was just sitting here pondering my problem, and had decided it must be a fuel issue and thought that maybe I had somehow got air in the lines, because that is the way it was acting. After reading your post, I thought I would try to blead the lines and sure enough that cured the problem. Works like a champ. I don't know how air got trapped in the system, but I tightened everything up and hope that doesn't happen again.

As always, thanks to all for the input.

tdelorme
10-27-2008, 10:23 PM
Tony it might happen if you let the fuel tank get down around a 1/4 tank like Dale suggested. Only other way I can think of is changing the filter. Even pre filling the filter will cause a big gulp of air.

Jon Wehrenberg
10-28-2008, 07:46 AM
FWIW if the generator has been unused for a long period somehow it seems fuel delivery to the injectors is compromised.

I have no clue if it bleeds throught the injectors over time, or back flows or even evaporates, but on my previous coach's generator I found if I primed it after it had been unused for a while it would start immediately.

That coach had a Kubota engine and priming was as simple as putting power to the fuel pump, and opening a small valve that allowed fuel to flow through the tubing to the injectors. I have not had the problem with my current Kohler with a Yanmar engine, but if it gets reluctant to start priming is the first thing I intend to do. If a diesel engine will spin all it needs to start is fuel.

hhoppe
10-28-2008, 08:49 PM
[ If a diesel engine will spin all it needs to start is fuel.[/QUOTE]

Jon: Please add to the above statement. " fuel through the injectors into the cylinders in a pre timed fashion." If the sensor that sends info on injector timing from a spinning flywheel to the DeDec engine computer is faulty or disconnected the fuel will not reach the cylinders. In this case No amount of engine starter fluid or other priming will alow the engine to start even momentarily. On a 8V engine that sensor is burried below the De Dec computer. When the computer is removed you will get a birds eye view of the sensor. The rafter rats found a nice warm cozy spot next to the sensor and proceeded to chew the wires in two. Another episode in Prevost madness.

jimshoen
10-28-2008, 11:07 PM
I had a similar problem on my PowerTech 20KW. Turned out that the fuel line had rubbed a small hole in itself and was sucking air and leaking a little fuel. This was the part of the fuel line that goes in and out with the generator as it is pulled out on the slide out. After 12 years and 8000 hours it just gave up. I replaced the fuel lines and protected them with the same spiral wrap used on backhoes etc. to protect the hydraulic lines. It should be bullet proof now.