My Genny in my motorhome can overheat sometimes and than it shuts down in the hottest part of the day when dry camping here in the west, its the Onan gas 5500 watt genny.Has anyone done anything to fix yours, was thinking of a fan sitting on ground under genny or ?..

It probably has a mouse nest blocking the airflow. Matt

Are you getting the "service soon" code flashes on the inside start switch?

I have the same generator and twice have had the same problem. Both times there was a little to much oil. Check the dip stick, if it is even a little over the full line, drain a small amount off and see if that takes care of the problem.Also, check what the code is. It will be the red light on the start button on the generator. You should have a manual for the generator and there is a place that will tell you what the blinking lights mean.

My oil and air filter is new, I do this at spring time every year, no mouse nest its all clean, when it does shut down and its not often just at the peak of the hottest part of a day above 95 degrees I check under the cover and its hot and I mean hot, I do keep my oil near the max mark but I cant see how this will cause more heat in the motor.Will have to check next time it shuts down to see what lights blink on the switch, however it runs fine and smooth but just hates the heat.

Genny Overheats and Shuts Down, How To Fix | Good Sam Community

31 Replies

wildmanbaker
Explorer
Jun 14, 2016
Tim, we drycamp a lot and run the gen when it is near 100, and have no trouble with our gen. I would look at the fuel system first before cutting the access door.
timmac
Explorer
Jun 10, 2016
filadelfia wrote:
wildmanbaker wrote:
Tim, you may want to check the fuel system on the gen, as this sounds like it may be vapor locking. A partially plugged fuel filter, or weak pump.

X2 seems like you would be getting an overheating trouble code if the engine was shutting-down on hi temp.
Good luck Don

Than maybe it is a vapor lock from to much heat buildup, I am getting no blinking light on switch after it shuts it self down, so fixing the heat issue is 1st than on to fuel filter and such and I should be OK..
427435
Explorer
Jun 10, 2016
If leaving the side door open solves your problem when parked, And opening in that door with a sheet metal scoop to pull air in when driving, should solve your highway problem. Might need a way to keep rain from getting in, however.
filadelfia
Explorer
Jun 10, 2016
wildmanbaker wrote:
Tim, you may want to check the fuel system on the gen, as this sounds like it may be vapor locking. A partially plugged fuel filter, or weak pump.

X2 seems like you would be getting an overheating trouble code if the engine was shutting-down on hi temp.
Good luck Don
wildmanbaker
Explorer
Jun 10, 2016
Tim, you may want to check the fuel system on the gen, as this sounds like it may be vapor locking. A partially plugged fuel filter, or weak pump.
mc_cc
Explorer
Jun 10, 2016
In my last coach, I had a Generac generator do that. I could never figure out what the problem was. The authorized service center would run it all day long in the parking lot and tell me there was nothing wrong with it. I would get it out on the interstate and it would shut down in the heat of the day, every time. I finally got so fed up, I had an Onan installed and never had another problem. I know that is not the answer you want to hear, but that was my only solution. I gave that generator to someone who assured me they could fix it. They told me they had done all kinds of work. It was fixed and they had installed it on their truck. A few months later, I asked again. He told me he had the same problem and could never figure out what the problem was.
timmac
Explorer
Jun 09, 2016
Effy wrote:

I have friends in Vegas and they said it's been consistently over 100 every day. Like 109 or some crazy temp. That's hot for an air cooled gen set sitting in a bin with no air flow, especially under a heavy load like AC's trying to keep up in an an RV.

When I camp around the SW in the summer I go for full hookups and wont use the genny, but when traveling out of state during the summer I like to dry camp along the way and use the genny, I try not to use it above 100 degrees if possible.
joe_b_
Explorer II
Jun 09, 2016
The generator in the OP's original post is about the 5.5 KW Onan, a twin cylinder gas engine model that Is a direct drive from the generator engine to the alternator/generator portion. There is no belt involved on these as there would be on a liquid cooled gas or diesel generator.
Effy
Explorer II
Jun 09, 2016
Ivylog wrote:
timmac wrote:
Ivylog wrote:
Can you move a fan blade by hand? A old belt while tight will start to slip... you can buy a spray belt dressing that will stop the fan from slippy. I would try that first and if that fixes it... A new belt is in order.

This thread is about the generator over heating, not the motor.

Gee... I did not know a generator does not have a motor with a fan or a fan belt??? :S
If all else fails I'd put a water mister in front of the air intake getting water from the outside shower. Just turn the water pump on when going down the road when you think you need it.

Ivy, you been sipping on grandma's cough medicine?
Ivylog
Explorer III
Jun 09, 2016
timmac wrote:
Ivylog wrote:
Can you move a fan blade by hand? A old belt while tight will start to slip... you can buy a spray belt dressing that will stop the fan from slippy. I would try that first and if that fixes it... A new belt is in order.

This thread is about the generator over heating, not the motor.

Gee... I did not know a generator does not have a motor with a fan or a fan belt??? :S
If all else fails I'd put a water mister in front of the air intake getting water from the outside shower. Just turn the water pump on when going down the road when you think you need it.