Onan 6500 Propane Generator

[Steve Adams]

This afternoon I tried to start the generator on our MH and it would not start. It turned over easily but would never catch. It did not sound as if it was getting any fuel at all. Where should I start or what shops would you recommend in the Portland, OR area?

Thanks, Steve

[LEAH DRAPER]

I am guessing but it is probably a Cummings gen....I'd definitely go to the Cummins dealer.  

[Gerald Farris]

Steve,
First make sure that you have propane available in the coach, by turning on a burner on the cook top. If you do not have propane in the coach, check the tank valve, to make sure that the valve was turned back on after the last time that you had it filled. Also, check the "propane sniffer", that is located close to the floor usually by the refrigerator, to make sure that it is on and operating normally.

Gerald

[Steve Adams]

Gerald,

We did use one of the burners to heat some water and had no problems getting it to run but I'll try it again just to be sure. The monitor panel says the propane tank is about 50% full. I'll check on the propane sniffer.

If the propane sniffer is defective or off would that prevent the genny from running? Is it interlocked some way?

Thanks for the help. Steve

[Gerald Farris]

Steve,
If the propane sniffer is off or defective, it will cut off all propane including your generator and cook top. That is why I told you to check the cook top to be sure that the propane was on before you try to have the generator serviced.

Gerald

[Steve Adams]

Gerald,

Thanks! I'll be heading out to check it today. We put it back in storage yesterday afternoon.

Thanks again, Steve

[Joel Ashley]

The best choice is Cummins NW out of Eugene where they regularly service motorhome units, but Olinger's/Camping World is closer, and also Cummins NW out near Swan Island in North Portland, but be aware of cost -

 http://www.bing.com/local/details.aspx?lid=YN720x12477247&qt=yp&what=cummins+northwest&where=Beaverton%2c+Oregon&s_cid=ansPhBkYp02&mkt=en-us&q=cummins+northwest&FORM=LARE

Curtis Trailers off Powell near I-205 is Onan certified, but is more into smaller trailer generators than motorhomes.

You might also consider Mobile RV Tech, which I used once a few years ago with satisfaction:

http://www.mobilervrepair.com/index.htm

-Joel

[Marty and Suzie Schenck]

On my '98 Monterey, there was a shut off valve at the tank, for both the vapor side and the liquid side. The vapor side supplies the refer, the hot water heater(if applicable) and the cook top or burners. The liquid side supplies the generator.  Make sure both are turned fully on, and then backed off 1/4 turn. Marty

[Edward Buker]

Steve,

If I remember right, there is a fuel solenoid valve that has to open at the generator. When you press the start button, there should be voltage on the solenoid valve. It should be on the incoming gas line, housed within the generator. You might try checking the voltage on that valve, and if voltage is present while cranking, you could also try tapping on that lightly with a small hammer, in case the valve is stuck. Beyond that, there is a large diaphram regulator mounted on top of the generator that sometimes gets clogged with very viscous oil, that can come from a contaminated batch of propane. Becuase the generator uses a liquid gas delivery, the oil can be carried along with it. I had to pull mine apart and clean it, but there is not too much user friendly stuff to work on in that fuel delivery system. As mentioned, there usually is a liquid propane valve of some kind, that needs to be open to supply the genset. It is at the tank. If you plan on pulling anything apart in the fuel system, be sure that the liquid propane supply valve is off, and whatever you take apart, check with a soap solution under pressure, after you put things back together, to be sure that there are no leaks.
later Ed

[Roy Mueller]

RV Generator Troubleshooting guide a service of Flight Systems, 505 Fish Creek RD. Dock 16 Lewisberry,PA. 17339
Ph. 717-932-9900  
FAX.717-932-9925  
WWW.flightsystems.com

If You need parts, they are USA made, at half the price. The Company is very helpfull. Propane GENS.
ROY MUELLER

[Steve Adams]

Update:

I've filled the oil, it was just at the bottom of the dipstick. I'll do a filter and oil change once it starts. Changed out the spark plugs, I think they were the originals. Filled the propane tank and ensured the liquid valve was fully open, then backed off a quarter turn. I checked the propane sniffer and it works, both the stove and reefer work. Generator will still not start.

A neighbor took off the air cleaner and shot some starting fluid in and it started right up and of course died when it ran out of fuel so that points to a fuel delivery problem. Reading the troubleshooting guide it says to replace F2 as it controls the fuel regulator. Where in the heck is F2? The diagram in the book shows a fused line near the control panel, I can only find F1 on the control panel and 2 circuit breakers. I've been over, under and behind the generator and cannot find anything resembling a fuse.

It looks like Ed was right on with a fuel problem. Not wanting to dismantle any of the fuel system, would anyone have a next best guess?

Thanks, Steve

[Edward Buker]

A fused line can sometimes mean a length of something that looks like wire that acts as a fuse. Not sure if that is what they did here. In a diagram a fuse looks like a bit like an S while a fuse link may not. If it is a fuse link it will look just like a short length of wire. You should be able to lift one end, measure it with an ohm meter and see if it is open. If so then replace it. By design it will have some resistance, maybe a few ohms or less.

You need to find out if they show a fuel solenoid valve at the generator. If they do then you need to find out if it gets voltage (12v) while you are cranking to be sure that it has the opportunity to open. If not, then you need to sort out why because it is an electrical problem with limited possibilities as to cause. That means there is a good chance you could replace a part and fix it yourself. If the correct voltage is on the solenoid then you need to take it somewhere that works on propane generators to have the fuel system sorted out.

later Ed

[Steve Adams]

Ed,

We checked the solenoid today. You can feel it clicking, though it is pretty weak. Both my neighbor and I though it would have been a more substantial click, but we feel it is working. I guess the next step is to clean the regulator. In all the paperwork I received with the coach, there were no diagrams of the generator. Where is the regulator in relation to the solenoid? Is the valve the solenoid operates, part of the regulator or separate? Is this something you've tackled, and if so, how did you test for fit after the repair? You mentioned soap bubbles, but will you be able to see all around this thing, once done?

Thanks in advance, Steve

[Edward Buker]

Steve,

The regulator on mine was a round unit maybe 6 inch dia on the top front of the generator. It had screws around the perimeter that removed, gently pried the top up, and pulled the rubber diaphram and spring. Mine had thick oil in it which I removed by mopping it up with a cloth. This regulator will not work right if oil restricts its movement. I had to hinge the generator down with a car jack on my install to work on it. You should be able to spray a soap solution and see enough to know if you are getting any leaking. Good luck with this. You may be at the point where you should get some help from Onan.

Later Ed

[Steve Adams]

Today was a busy day for me. Took the solenoid, valve and filter out and cleaned them up a bit and could not find any thing apparently wrong with any of them. As we were trying to determine next steps we just decided to put it all back together and see what happened. Bingo! It fired right up and ran great. Our best guess is that we had a bad ground on the solenoid which kept it from opening when voltage was applied. At least that's my story and I'm sticking to it.

Thanks to everyone for their assistance.

Steve