Onan shuts off while driving/hot
Hi there, Having an annoying issue with my Onan 4000 gas generator that is only an issue while driving the motorhome. While stationary its perfect. So if the genset is running while driving down...
Forum Discussion
a couple of comments on the problem with generator shutdowns in higher ambient temps; 1st...NEVER run a 4KY(microlite/Microquiet) or newer 5.5 and 7000 Onan gens
with service door removed (except for a quick adjustment maybe).
They will not run cooler, just the opposite. And the mufflers will get hot enough to melt the fiberglass covers. They come with a warning label on the base tray stating this. Hot weather seems to bring out the worst in these air cooled units. Vapor locking can occur if temp in gen compartment is high enough. we have acheived some success by moving fuel pump to cooler location, outside the gen compartment. Only do this on commercial applications, e.g., food trucks, grooming vans, etc.
Most often a fuel pump problem, as they can just stop pumping if they get hot enough. The other problem that we commonly see is the control board stops supplying voltage to fuel pump when it gets hot....usually will restart after a cool-down period. The intermittant nature of problem often makes diagnosis difficult
with service door removed (except for a quick adjustment maybe).
They will not run cooler, just the opposite. And the mufflers will get hot enough to melt the fiberglass covers. They come with a warning label on the base tray stating this. Hot weather seems to bring out the worst in these air cooled units. Vapor locking can occur if temp in gen compartment is high enough. we have acheived some success by moving fuel pump to cooler location, outside the gen compartment. Only do this on commercial applications, e.g., food trucks, grooming vans, etc.
Most often a fuel pump problem, as they can just stop pumping if they get hot enough. The other problem that we commonly see is the control board stops supplying voltage to fuel pump when it gets hot....usually will restart after a cool-down period. The intermittant nature of problem often makes diagnosis difficult
