2022 395MS generator acting up.

[bsonposh]

Hello friends!

I will try to keep this informative but brief. Today we lost house power and I tried to start the generator (Onan 5500 gasoline.) Unfortunately, it would start for like a few seconds and then die. After several moments on the internet I learned how to get the service code which in this case is 36.

Its basically brand new (less than 50hrs) and I believe it has sufficient fuel. It is a toy hauler so it has two tanks in the back and to be honest I am not sure what the heck is going on there. The meter says the generator has fuel but /shrug. If anyone can enlighten me on how those tanks are suppose to work I'd appreciate it.

All that to say... I think the next thing to check is the fuel pump... anyone know where that is?

Thanks,
Todd

[TedS]

Is there a generator fuel valve that is not turned on?

[bsonposh]

TedS it is certainly possible but I am not sure. I have started it before but not often. We are full timers and are attached to shore power almost 100% of the time.

[Jlawles2]

Some of the generators will not run if the fuel tank is below 1/4. How much fuel is in the tank? Can you hear the fuel pump running for the generator? Does the Gen have a fuel filter, try changing it (I know 50 hrs, but stranger things have happened).

Also verify oil level and if possible that it has oil pressure.

[TedS]

One other thing to do. Open the fuel bowl drain valve to see if gasoline is getting to the engine.

[familytruckster4]

Always solve for the easy things, add some fuel to the tank. (preferably zero ethanol "rec Fuel")

[bsonposh]

Some of the generators will not run if the fuel tank is below 1/4. How much fuel is in the tank? Can you hear the fuel pump running for the generator? Does the Gen have a fuel filter, try changing it (I know 50 hrs, but stranger things have happened).

Also verify oil level and if possible that it has oil pressure.

The tank has about 20 gals in it (assuming I put it in the correct one.) I would love to know where the fuel pump is so I can see if it is turning on.

[JCR GD]

The tank has about 20 gals in it (assuming I put it in the correct one.) I would love to know where the fuel pump is so I can see if it is turning on.

Should be the forward tank.

[Richkeith]

Any resolve on this issue. I am having the same issue and my wife, 2 year old and myself are sitting in a hurricane with a full tank of fuel and my 2024 395ms generator won’t start. I also probably have run it for 50 hours with no issue and now it started once for a few minutes and died. Now seems like it isn’t getting fuel.

[JBill9694]

As Jim stated, the forward tank is the generator tank. If fuel was added to the rear tank, the nozzle for filling toys can be used to move the fuel from the rear to the forward tank. Unless all the fuel in the tank will be used in one trip, add a stabilizer to the fuel. I use a marine grade stabilizer which helps prevent moisture absorption. Even with the stabilizer it is a good idea to run the tank dry (no drain valve) every so often and start fresh.

I believe, but it has been a while since I looked, that there are two fuel pumps, one at the tank and in the generator, that work in concert to get the fuel from the tank to generator.

As Ted suggest, check and see if fuel is getting to the generator. As Joe suggest, check the fuel filter and make sure there is oil. At 50 hours of run time, both generators should have their first maintenance performed.

Finally, generators need to be exercised every so often (I do mine every 4 months) by running at 50% load for a couple of hours. A side benefit is that if the generator needs servicing this will likely show up during exercising instead of during a power outage.

[2chrisd]

Any resolve on this issue. I am having the same issue and my wife, 2 year old and myself are sitting in a hurricane with a full tank of fuel and my 2024 395ms generator won’t start. I also probably have run it for 50 hours with no issue and now it started once for a few minutes and died. Now seems like it isn’t getting fuel.

Hi. My gut feeling when a perfectly good generator will not start is a gummed up carburetor. I highly recommend that you use a product called ONAN Fresh as a fuel preservative. Or at least add some sea foam to the generator fuel. This problem is caused by ethanol in the fuel. Gas generators need to be exercised monthly- that is letting them run under load for a few minutes monthly. I run mine for about 20 minutes every month. I have had my unit since 2013 and never once had an issue. The problem is letting them sit with fuel in the lines.

The probable fix is to clean the carburetor out.

I hope things worked out for you.

Chris.

[Reacher]

Hi. My gut feeling when a perfectly good generator will not start is a gummed up carburetor. I highly recommend that you use a product called ONAN Fresh as a fuel preservative. Or at least add some sea foam to the generator fuel. This problem is caused by ethanol in the fuel. Gas generators need to be exercised monthly- that is letting them run under load for a few minutes monthly. I run mine for about 20 minutes every month. I have had my unit since 2013 and never once had an issue. The problem is letting them sit with fuel in the lines.

The probable fix is to clean the carburetor out.

I hope things worked out for you.

Chris.

You are absolutely right Chris. Simply draining the carburetor float bowl before seasonal storage or if you don't intend to use the generator for more than six weeks will solve a lot of headaches. This worked better for me than exercising the generator monthly, or using a fuel additive.