Onan 7500 Quiet Diesel Generator no start

[HRF]

The generator in my 2007 Fleetwood would not start after the MH was sitting in storage for 5 days with the battery disconnect switches off. The generator set a fault code 32 and said low battery and slow crank speed. The batteries were almost fully charged and when I tried to start the unit again 3 days later, it started okay. Then 2 days later it would not start and set code 32 again. Coach is not plugged in and the batteries check okay. Any ideas as to what would cause it to not start one day and start okay 3 days later, only to fail again 2 days after that?

[Jake21]

Have you tried cleaning all the battery cable connections? I would start there.

[HRF]

Battery cables were cleaned this spring and appear to be okay but I will check.

[blendabowl]

I too am having troubles getting my BRAND new onan to start it has 78 hours on it. For the first 70 hours, no problems. Replace oil and filter at 37hrs.
This is on a food truck .

The truck batteries have a kill switch on them to prevent draining.

The last 3 times I have tried to use generator, I get one crank then Nothing....

the first two times, I put jumper cables to the generator and was able to start right up. this last time, it did not do the trick.


Still not starting. Any advice? Anyone have a problem like this? Of course its a weekend and there isn't a shop open until Monday.

Any experience with this or advice would be appreciated....

[HRF]

Don't know if new generators set codes like my 2007 does but on mine the light in the start/stop switch will flash a code. Count the flashes. Mine flashed 3 times paused and flashed 2 times for a code 32. Your owners manual should tell you about codes.

[TwelveVolt]

The first questions in electronics troubleshooting are “Is it plugged in.” and “Is it turned on?”. For generators it is “Does the tank have enough fuel?”. The generator usually requires more than 1/4 tank, but possibly more if parked on an incline. If it was low at any time, even though it is full now, fuel may have dropped out of the tube to be replaced with air. If you hold the switch in the off position for 60 seconds, the pump will run to push air through and replace it with fuel.

I know the problem here seems to be the battery, but you did not say how long you were cranking before getting the battery low condition.

[Truckerdave]

Mine is an older model. 1993. Generator starts hard after sitting a few months. Cranks but does not start. When it does start it runs ruff for about 30 seconds then smooths out. Half a tank of diesel fuel. I am guessing mine is losing its prime.

[aboatguy]

Originally Posted by Truckerdave

Mine is an older model. 1993. Generator starts hard after sitting a few months. Cranks but does not start. When it does start it runs ruff for about 30 seconds then smooths out. Half a tank of diesel fuel. I am guessing mine is losing its prime.

If your 7.5 qd is like my 1997, if you push the bottom side of the start switch it operates the electric lift pump and should prime the generator.

[aboatguy]

Originally Posted by HRF

The generator in my 2007 Fleetwood would not start after the MH was sitting in storage for 5 days with the battery disconnect switches off. The generator set a fault code 32 and said low battery and slow crank speed. The batteries were almost fully charged and when I tried to start the unit again 3 days later, it started okay. Then 2 days later it would not start and set code 32 again. Coach is not plugged in and the batteries check okay. Any ideas as to what would cause it to not start one day and start okay 3 days later, only to fail again 2 days after that?

Are you checking the voltage after the disconnect switch (maybe the switch is causing a voltage drop) ?



Are all the connections clean and tight?


What's the battery voltage at the generator when it won't start?


Mike

[HRF]

The generator is in the front of a Fleetwood motor home and not on a slide out tray. Where do I go to check voltage at the generator? Under the coach?

[HRF]

Originally Posted by TwelveVolt

The first questions in electronics troubleshooting are “Is it plugged in.” and “Is it turned on?”. For generators it is “Does the tank have enough fuel?”. The generator usually requires more than 1/4 tank, but possibly more if parked on an incline. If it was low at any time, even though it is full now, fuel may have dropped out of the tube to be replaced with air. If you hold the switch in the off position for 60 seconds, the pump will run to push air through and replace it with fuel.

I know the problem here seems to be the battery, but you did not say how long you were cranking before getting the battery low condition.

Thanks. The bottom half of my start button will prime and my tank level was a little over 1/4 full so maybe you are on to something that I did not think of. I will try when I get to the coach in a couple of days. However the generator was running but 3 days later with no decrease in fuel tank level, it would not start. Also it does not crank, just clicks for preheat for 10 seconds or so then nothing. The light then flashes the code 32 so I don't think it is a fuel issue but you never know. Thanks for the suggestion.

[okcnewbie]

Originally Posted by HRF

The generator is in the front of a Fleetwood motor home and not on a slide out tray. Where do I go to check voltage at the generator? Under the coach?

If you have a panel that removes from your genset than just inside that you should be able to follow the red cable to the relay.

You should be able to find the owners and service manuals here.
Index of /~n0nas/manuals/onan

[Tha_Rooster]

Originally Posted by HRF

The generator in my 2007 Fleetwood would not start after the MH was sitting in storage for 5 days with the battery disconnect switches off. The generator set a fault code 32 and said low battery and slow crank speed. The batteries were almost fully charged and when I tried to start the unit again 3 days later, it started okay. Then 2 days later it would not start and set code 32 again. Coach is not plugged in and the batteries check okay. Any ideas as to what would cause it to not start one day and start okay 3 days later, only to fail again 2 days after that?

When you say batteries are ok what is the house batteries voltage?

[HRF]

Originally Posted by okcnewbie

If you have a panel that removes from your genset than just inside that you should be able to follow the red cable to the relay.

You should be able to find the owners and service manuals here.
Index of /~n0nas/manuals/onan

Thanks. I do have a panel and have never looked under it. I will check it out.