Author Topic: Massive fuel leak  (Read 5037 times)

Fred Cook

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Massive fuel leak
« on: May 20, 2020, 03:32:21 PM »
I have a massive fuel leak at the bottom of my fuel tank when running the generator. It does not leak when running the aqua hot or running the motor... only leaks when running the generator. Any ideas would be appreciated.
Fred & Cindy
2002 Beaver Patriot Thunder 455, C12 CAT
Towing 2019 Chevy Equinox, AWD Diesel
South Central Missouri, US Army Retired

Lee Welbanks

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Re: Massive fuel leak
« Reply #1 on: May 20, 2020, 03:47:11 PM »
Fred, I don't know but does a diesel Onen have a fuel return line? I would have to go out and look at mine. What location is the fuel leaking, fuel tank, generator or somewhere in between.

Steve Huber Co-Admin

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Re: Massive fuel leak
« Reply #2 on: May 20, 2020, 03:49:18 PM »
Fred,
Sounds like the line from the tank to the generator is leaking at or very close to the tank It probably needs the pressure of the fuel pump to force the fuel out of the leak.
Steve
Steve
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Fred Cook

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Re: Massive fuel leak
« Reply #3 on: May 20, 2020, 04:23:57 PM »
Fred, I don't know but does a diesel Onen have a fuel return line? I would have to go out and look at mine. What location is the fuel leaking, fuel tank, generator or somewhere in between.

Lee, its leaking from the bottom center of the fuel tank.  It sounds weird because I do not see any kind of a fuel line going to or coming from that area.  There is a metal band strip about 3 inches wide supporting the fuel tank underneath  and leak appears to be coming between that band and the tank.
Fred & Cindy
2002 Beaver Patriot Thunder 455, C12 CAT
Towing 2019 Chevy Equinox, AWD Diesel
South Central Missouri, US Army Retired

Lee Welbanks

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Re: Massive fuel leak
« Reply #4 on: May 20, 2020, 04:31:54 PM »
Can you see the top of the tank? The fuel could be running down from the top and using the strap as a guide, if your tank was leaking from the bottom it would leak all the time. Has to be coming from the suction fuel line to the gen, I don't think they have return lines.
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Fred Cook

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Re: Massive fuel leak
« Reply #5 on: May 20, 2020, 04:45:49 PM »
 Nope, can’t see the top of the tank.  You may be correct that metal band is hiding the return line. I just talked to a repair shop and they believe it may be coming from the generator return line because the generator continues to run while leaking. I have an appointment to take it there tomorrow for them to look at and fix it. Thanks!
Fred & Cindy
2002 Beaver Patriot Thunder 455, C12 CAT
Towing 2019 Chevy Equinox, AWD Diesel
South Central Missouri, US Army Retired

Frank Bergamo

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Re: Massive fuel leak
« Reply #6 on: May 20, 2020, 05:00:32 PM »
Fred, there is a return line that runs from the lower right side of the generator to the top of the fuel tank. The feed line is also in the same location. You will have to follow the line to the top of the fuel tank. Probably a loose clamp or a bad hose going into tank. Hope this helps!
Frank & Paulette Bergamo
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Carl Boger

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Re: Massive fuel leak
« Reply #7 on: May 20, 2020, 06:39:24 PM »
Fred I believe that you have the same set up as I do, and there are both supply and return lines coming from the top of the tank going to the generator.  I had to replace my lines, and had to drop the tank to do it.  Since my tank was full I had to get 2 clean 55 gallon drums that had permanent tops and transfer the fuel to them so I could safely drop the tank.  Mine leaked on the return side, but the lines were pretty worn out on both sides.

There is really not much room under that area to work so if you can get to a pit that would be ideal.
Carl

98 Beaver Patriot Savannah
330 hp Cat 3126
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Eric Maclean

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Re: Massive fuel leak
« Reply #8 on: May 20, 2020, 06:42:50 PM »
Fred
On my 97 PT
The Onan diesel has two lines feed and return that run from behind the gen set up and along the pass side frame rail where they disappear between the tank and the frame rail.
A year ago after having the gen set slide out after I put it back in I developed a large leak.
The return line ( or both lines for that matter had turned hard with age and when the gen moved in and out the lines cracked at the bend near the fuel tank.
You may find your lines have done the same .
The bad part is that on order to get to the top of the tank where the lines originate you have to drop the fuel tank which inturn means removing front axle.
On mine I replaced the lines as close to the tank as I could which covered the bad area but yours sounds like it's above the tank where it's leaking as the fuel is running off the tanks itself.
I just had the front axle out of my coach and the bolts where seized in the axle and caster blocks not fun.
I don't envy the job ahead of you
Good luck
Eric
1997 Patriot Yorktown
3126-B
2009 Chevy HHR
Roadmaster falcon tow bar
Demco Air Force one tow brake.
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Fred Cook

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Re: Massive fuel leak
« Reply #9 on: May 20, 2020, 11:17:45 PM »
Fred
On my 97 PT
The Onan diesel has two lines feed and return that run from behind the gen set up and along the pass side frame rail where they disappear between the tank and the frame rail.
A year ago after having the gen set slide out after I put it back in I developed a large leak.
The return line ( or both lines for that matter had turned hard with age and when the gen moved in and out the lines cracked at the bend near the fuel tank.
You may find your lines have done the same .
The bad part is that on order to get to the top of the tank where the lines originate you have to drop the fuel tank which inturn means removing front axle.
On mine I replaced the lines as close to the tank as I could which covered the bad area but yours sounds like it's above the tank where it's leaking as the fuel is running off the tanks itself.
I just had the front axle out of my coach and the bolts where seized in the axle and caster blocks not fun.
I don't envy the job ahead of you
Good luck
Eric
[/quote

Thank... I’m having it worked on and hoping it does not cost a fortune.
Fred & Cindy
2002 Beaver Patriot Thunder 455, C12 CAT
Towing 2019 Chevy Equinox, AWD Diesel
South Central Missouri, US Army Retired

Carl Boger

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Re: Massive fuel leak
« Reply #10 on: May 20, 2020, 11:32:50 PM »
Fred,
Eric,

I did not have remove the axle on mine to replace the fuel lines.  I have about 6 or 7 inches from the bottom of the tank to the axle.  After emptying the tank and dropping it to the axle I was able to tilt the back of the tank up with a jack and get to the fittings on the top of the tank.  It is not a fun job and it is very tight in the area.  Most of it was done by feel, glad I have long arms! 
Carl

98 Beaver Patriot Savannah
330 hp Cat 3126

Eric Maclean

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Re: Massive fuel leak
« Reply #11 on: May 21, 2020, 01:15:07 PM »
Thanks Carl it's good to know I won't have to take those axle bolts out again
Eric
1997 Patriot Yorktown
3126-B
2009 Chevy HHR
Roadmaster falcon tow bar
Demco Air Force one tow brake.

Fred Cook

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Re: Massive fuel leak
« Reply #12 on: May 21, 2020, 02:07:00 PM »
Fred,
Eric,

I did not have remove the axle on mine to replace the fuel lines.  I have about 6 or 7 inches from the bottom of the tank to the axle.  After emptying the tank and dropping it to the axle I was able to tilt the back of the tank up with a jack and get to the fittings on the top of the tank.  It is not a fun job and it is very tight in the area.  Most of it was done by feel, glad I have long arms!

Yep, I called BCS and talked to Sean. He pretty much described the procedure the way you did it. Trouble is, I don’t have the tools or mechanical savvy to do the job myself so I’m having it done at a truck repair facility. I am just hoping they understand what and how it needs to be done and that they do a good job. It’s Ryan’s 24/7 Truck repair in St Clair, Mo and they have good reviews. I will let all know how it all turns out.
Fred & Cindy
2002 Beaver Patriot Thunder 455, C12 CAT
Towing 2019 Chevy Equinox, AWD Diesel
South Central Missouri, US Army Retired

Eric Maclean

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Re: Massive fuel leak
« Reply #13 on: May 21, 2020, 03:52:05 PM »
Fred
I have heard on the forum here of people abandoning the return line and teeing into the return line for the aquahot maybe this will work for you.
Eric
1997 Patriot Yorktown
3126-B
2009 Chevy HHR
Roadmaster falcon tow bar
Demco Air Force one tow brake.

Fred Cook

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Re: Massive fuel leak
« Reply #14 on: May 22, 2020, 11:51:49 AM »
Fred
I have heard on the forum here of people abandoning the return line and teeing into the return line for the aquahot maybe this will work for you.
Eric

Hmm... interesting. Would you still be able to run the generator and aqua hot at the same time?
Fred & Cindy
2002 Beaver Patriot Thunder 455, C12 CAT
Towing 2019 Chevy Equinox, AWD Diesel
South Central Missouri, US Army Retired