Onan 5500 problem

[taboky]

Always exercised genny with out a problem. Coming home today, after running genny for first time while driving, it was off after 15 minutes using both AC's. Started right up and probably another 15-20 minutes it was off. Got home and ran it with both AC's for an hour, no problem. The code is 36-Engine stopped without command by controller. I have plenty of fuel. When it cools, I will check that the plug boots are secure. There is only 12 hours on genny. And it seems to only happen while driving.

So, where should I start looking?

["007"]

Check your 12V power and battery ground cables to chassis frame.
May have something shaking loose.

[Jackm]

Steve,

Check out the post from mrschwarz titled "Intermittent Roof AC when driving" on the Winnebago forum. It describes a problem with the transfer switch when a vehicle is in motion. It sounds very similar to your situation. Best of luck.

Jack

[taboky]

Thanks Jackm, but I don't have transfer switch. Direct plug in. (30 amp).

"007", I figure it may be something loose. My question is what would be loose that would shut off the genny. Would it stop running with no 12v? If it looses 12v, is that same as hitting off switch? If so, wouldn't it be like I hit the switch and be a "command"? I will check out all the battery connections also on the genny side.

[jlyon69]

Quote:

Originally Posted by taboky "007", I figure it may be something loose. My question is what would be loose that would shut off the genny. Would it stop running with no 12v? If it looses 12v, is that same as hitting off switch? If so, wouldn't it be like I hit the switch and be a "command"? I will check out all the battery connections also on the genny side.

I'm no expert, especially on the newer genny systems. I can tell you the fuel pump and any control system/board runs on 12v. So if you lose 12v, the genny isn't going to run. If the genny runs when the coach is sitting still, it would seem logical to assume that any bad connection is somewhere other than on the genny itself. But I've seen stranger things! Good Luck.

[Clay L]

Quote:

Originally Posted by taboky Always exercised genny with out a problem. Coming home today, after running genny for first time while driving, it was off after 15 minutes using both AC's. Started right up and probably another 15-20 minutes it was off. Got home and ran it with both AC's for an hour, no problem. The code is 36-Engine stopped without command by controller. I have plenty of fuel. When it cools, I will check that the plug boots are secure. There is only 12 hours on genny. And it seems to only happen while driving. So, where should I start looking?

The 36 code covers a lot of ground as I recall.

In my case it was an intermittent air leak at a hose clamp where the fuel line transitions from rubber to metal near the fuel tank. The vibration while driving seemed to cause the leak.
The symptoms were similar to those you described.

[taboky]

I checked all electrical connections and fuel connections. All nice and tight. I did have a thought. I remember one time after driving (no genny) awhile, when I got out with engine still running and got near fuel fill, there was one hell of an air noise from the cap. When I opened it, BIG WHOOOSSSHHHH. Can't remember, is the tank supposed to be vented at the cap? Could there be too much vacuum for the pump on the genny?

Just throwing out things now........

[jlyon69]

You might be onto something and it's easy enough to test your theory. Loosen the fuel cap, fire up the genny, both ACs and go for a drive.