Generator issue

[BZP]

I have a 2004 Winnebago Journey with a 7.5 kw Onan diesel generator. Until recently I have had no problems. I do all the scheduled maintenance and my oil level is good. My generator will shut down if I have low fuel levels and I recently had that happen. After I got fuel again, the generator worked fine for a few days. Then when I started it, it ran for a few seconds and shutdown and would not start again. However, after a few hours it started just fine and worked normally for about a week. Then it all happened again. Does anyone know why my generator will sometimes shut down soon after starting? When it trips the light on the switch blinks three times repeatedly. From the manual, this indicates a shutdown due to abnormal conditions? Is there something simple I can do or do I need to take it to the shop? Thanks

[twinboat]

It shouldn't be dirty diesel plugging the filters, from the tank, because it pulls fuel from above the botton.

When was the last time you had the filters serviced ?

You may also want to check every fuel line connection from the tank to the generator. The slights loosness will cause air to be drawn in, causing shutdowns.

Just some things to check.

[pyronh1]

we had that problem on our 2008 elegro bus and was told we had to have it taken out to bench test with a big cost .when they went to do the work they found a line filter up by the tank that was clogged . we spent over 1000.00 trying to have this problem solved the put in new lines and left the inline filter out runs great now

[R.Wold]

Usually the fuel pick-up is placed at the 1/4 tank level so that it wont run you out of fuel. Having done that maybe you have air trapped in the fuel system. You might try purging it. Not having worked on diesel onan generators I dont know if and where a bleed valve might be located but the manual should address this.

You should be getting a 2 digit code:

• 3 flashes indicates a service fault (Code 3 fault)

To get your 2 digit code:

Press STOP/PRIME on the control switch once to have the 2-digit service fault code flash.
The 2-digit code consists of two sets of flashes. The first set is of flashes represents the 10s digit of the code. After a brief pause, the second digit of the code flashes representing the unit digit of the code. This is followed by a long pause before repeating the flashing of the fault code.
For example, Fault Code 36 appears as: blink-blink-blink—pause—blink-blink-blink- blink-blink-blink—long pause—repeat
Press STOP/PRIME to stop flashing the fault code.

Fault Code Nos. 3 and 4 are first level faults. Avoid interpreting them as second-level Fault Code Nos. 33 and 44, which have not been assigned as fault codes.

Restoring Fault Code Blinking – The fault code stops blinking after five minutes (15 minutes, Series HGJAA). Press Stop three times within five seconds to restore blinking. Note that the last fault logged will blink, even after the condition that caused the shutdown has been corrected

Check the simple stuff first. If its like most rv gensets its ready for a new fuel filter anyway and running it out of fuel might have pulled crud from the filter housing into the filter element. Its probably the most common cause premature shutdown so you could try that. Cheap and cant hurt.

Id take it to an RV shop as a last resort. Ive read numerous accounts of people being way overcharged for almost every type of service at those places.

[twinboat]

Originally Posted by R.Wold

Usually the fuel pick-up is placed at the 1/4 tank level so that it wont run you out of fuel. Having done that maybe you have air trapped in the fuel system. You might try purging it. Not having worked on diesel onan generators I dont know if and where a bleed valve might be located but the manual should address this.

You should be getting a 2 digit code. Under service code 3, it says “see second level fault code”.

To get your 2 digit code:

Press STOP/PRIME on the control switch once to have the 2-digit service fault code flash.
The 2-digit code consists of two sets of flashes. The first set is of flashes represents the 10s digit of the code. After a brief pause, the second digit of the code flashes representing the unit digit of the code. This is followed by a long pause before repeating the flashing of the fault code.
For example, Fault Code 36 appears as: blink-blink-blink—pause—blink-blink-blink- blink-blink-blink—long pause—repeat
Press STOP/PRIME to stop flashing the fault code.

Check the simple stuff first. If its like most rv gensets its ready for a new fuel filter anyway so you could try that. Cheap and cant hurt. Id take it to an RV shop as a last resort. Ive read numerous accounts of people being way overcharged for almost every type of service.

The OP said it ran normally, If it does, there is no trapped air.

The fuel system circulates fuel thru the engine and sends what it doesn't use back to the tank. The system is designed not to leave pockets of air in the fuel lines or filters.

[R.Wold]

Ok, thanks for that info - good to know. So the mystery probably lies in the two-digit fault code, or the fuel filter....

[Outbound]

Looking elsewhere have you checked your coolant/oil levels, could be kicking off on safety switch.

[Gary RVRoamer]

All the earmarks of a dirty filter for the genset, so time to repalce. Change the air and oil filters while you are at it.

[mlh2013]

As others have said, start with changing fuel filter, if engine is starving for fuel it will stall when under a load.

[Tpodbevsek]

Ok so I had service done on the generator. Simple oil change. Had issues running it and starting. I eventually cleaned the carbs changed the two filters for fuel and the fuel pump. Runs much nicer and just finished running sea foam through the carb and everything is nice and clean. Generator remained running only when I get the choke pinned or closed slightly. If I leave the air cleaner over off also stays running. If I close it up it start to choke sputter and then shuts off. This happens less if I pull power from the main output but again holding the choke makes everything go ok. It almost seems like the choke heater is bad something I haven't checked yet rain and working too much. The exhaust has a little more fuel smell than I would say is normal. I have blown the full lines back into the gas tank as well. I have also cleaned and replaced the line from the fuel pump to the carb. Is this a choke control? or is this a carb change?
I live in South Texas been cold and warm same result same symptoms each time.

[BZP]

Thanks everyone for your valuable responses. Here is an update. I changed my fuel, oil and air filters just before starting this trip and should have only about 10 hours genset operation since then. I don’t think a filter is my problem. My two digit fault code is “36” which is fuel interruption and/or air filter. My problems began when I ran the genset out of fuel and I did not prime the system afterwards. I have now primed per the manual instructions and will see if this resolves the problem. If it doesn’t do it, I will give you another update. Thanks again,
Barb & Bill

[Tpodbevsek]

I ran the generator again with very similar issues not staying running with the system shut up. I bought new carb off amazon for under $100. Twenty minutes later installed and cleaned. She fired right up and did not smell like unburnt fuel. I had the thing running shut up for about 40 mins with no issues. I ran the unit again while putting in back into storage for an hour. Again no issues. SO I am back in business. This was a simple easy fix and although the cheaper version of the carb has thinner linkage arms etc the design is exactly the same. I will be going out in another 30 days and will make sure to run the system again in between.

Originally Posted by Tpodbevsek

Ok so I had service done on the generator. Simple oil change. Had issues running it and starting. I eventually cleaned the carbs changed the two filters for fuel and the fuel pump. Runs much nicer and just finished running sea foam through the carb and everything is nice and clean. Generator remained running only when I get the choke pinned or closed slightly. If I leave the air cleaner over off also stays running. If I close it up it start to choke sputter and then shuts off. This happens less if I pull power from the main output but again holding the choke makes everything go ok. It almost seems like the choke heater is bad something I haven't checked yet rain and working too much. The exhaust has a little more fuel smell than I would say is normal. I have blown the full lines back into the gas tank as well. I have also cleaned and replaced the line from the fuel pump to the carb. Is this a choke control? or is this a carb change?
I live in South Texas been cold and warm same result same symptoms each time.