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MrsChilerick · 06-19-2017, 06:01 PM

Outside temp is 115. Had to pick up the MH from the mechanic. Turned on the genny to run the house air and when we got the coach home the genny wasn't running. Is this normal?

Adamsta · 06-19-2017, 06:08 PM

How much diesel was in the tank?

MrsChilerick · 06-19-2017, 06:24 PM

It's gas, just filled the tank.

**CLIFFTALL** · 06-19-2017, 06:26 PM

Common issue on an Onan 5500 is the fuel pump. Ask me how I know.

MrsChilerick · 06-19-2017, 06:34 PM

Quote:

Originally Posted by Clifftall

Common issue on an Onan 5500 is the fuel pump. Ask me how I know.

Ok, I'll bite, how do you know?

**CLIFFTALL** · 06-19-2017, 06:37 PM

I replaced mine [emoji16]

kenandterry · 06-19-2017, 06:40 PM

I have a Generac genny that shuts down, mostly while on the move. Could be fuel starvation with gasoline sloshing around the fuel bowl...high temps from pavement...high temp oil sensor...pick one. Not perfectly, but mine usually runs better if parked.

These things are so cheaply designed they still have carburetors, and I'll bet fuel injection versions(if they even exist) would be much better.

Just my opinion.

In Pursuit · 06-19-2017, 07:17 PM

My Onan genny was stopping in the heat also, thought the fuel pump again. Replaced our July last year. Funny thing it would start and run for 1 or 5 minutes. So not the fuel pump. I checked the oil level and was over filled. Pumped out about a pint until showed below full
Ran the rest of the day and for last two days while on the road and parked.
Check yours

MrsChilerick · 06-19-2017, 07:40 PM

Yeah, ours runs fine unless it's over 108 or so.

manderson2228 · 06-19-2017, 07:53 PM

There is nothing i need more at 108 degrees than the generator so i can run the AC

Adamsta · 06-19-2017, 07:55 PM

Just learned to never go camping if temps are over 108....

mrt_1111 · 06-19-2017, 08:06 PM

Quote:

Originally Posted by MrsChilerick

Ok, I'll bite, how do you know?

Same reason I know

bluepill · 06-19-2017, 08:19 PM

Quote:

Originally Posted by MrsChilerick

Outside temp is 115. Had to pick up the MH from the mechanic. Turned on the genny to run the house air and when we got the coach home the genny wasn't running. Is this normal?

I could simply be vapor lock, which can happen at elevated temperatures.

From Wikipedia:

Vapor lock is a problem that mostly affects gasoline-fueled internal combustion engines.
It occurs when the liquid fuel changes state from liquid to gas while still in the fuel delivery system. This disrupts the operation of the fuel pump, causing loss of feed pressure to the carburetor or fuel injection system, resulting in transient loss of power or complete stalling. Restarting the engine from this state may be difficult.
The fuel can vaporize due to being heated by the engine, by the local climate or due to a lower boiling point at high altitude. In regions where higher volatility fuels are used during the winter to improve the starting of the engine, the use of "winter" fuels during the summer can cause vapor lock to occur more readily.

ualdriver · 06-20-2017, 01:55 AM

Quote:

Originally Posted by MrsChilerick

Outside temp is 115. Had to pick up the MH from the mechanic. Turned on the genny to run the house air and when we got the coach home the genny wasn't running. Is this normal?

Not an unheard of problem. When I had my Fleetwood Storm with 4000W generator, it would shut down under high temps (90+), right when you needed it most. If you search on the topic, you'll find that there are a few solutions to the problem to help mitigate the issue. This includes replacing the fuel pump, putting 2 fuel pumps in series, modifications to the generator air intakes, putting in a fuel re-circulation line to keep the fuel from vapor locking, etc.