Community Forums

DonBren · 08-21-2011, 08:48 AM

A while back I posted my problem not getting gas to the gen. carb. I have determined the problem is a faulty gas line at or near the top of the tank connection, which I can not access, or a faulty pick up tube. I have had several helpful suggestions from dropping the tank to adding an aux. fuel line and inserting it in the same connection as the present vent line. Thanks dieselacker for the idea and I think I am going to go that route, almost. I had two concerns and need some opinions as to whether it is do able. I found my tank to have two spots to install the hose, one is the side that is also being used as the tank vent and gas fill line and on the other side of my tank is the same setup but they are plugged, I guess in case of a passenger side fill location if needed. I was a little nervous installing in the same vent as I have trouble sometimes filling up, shuts the nozzle off a lot so since these unused spots are available I think it would be an ideal set up. I am mainly concerned with the condition or life of the rubber hose when it is permantely emersed in the gas tank. I actually was going to drop the tank, had gas drained except for about 15 gallons but than I was concerned about breaking some of the connections on top of the tank when lowering the tank. I have a couple of rigid steel lines going to front of coach plus the gas line and they are all running the frame rail with no place to disconnect near the tank. The tank has to come down a minimum of 16 inches and I know the steel lines will not bend or stretch that much and I think it will put too much pressure on the fittings on top of the tank. It seems like there was no consideration at all when body was installed on chassis for removing the tank, even the hose clamps are not facing down, seems like everything was installed from top. Anyway, I could use some constructive comments as to this project. Thanks in advance, Don08694@aol.com

dieselclacker · 08-21-2011, 09:30 AM

Don,
I used 1/4" OD nylon plastic type line when I did the fix on my system. You can get it at any parts store. I didn't have the choice of an opposite side opening on the tank, so went in thru the vent line.
You may have a better option with your set up. Something you will have to decide on.

On that pump cutting off problem while filling the tank, check and make sure there are no places where the vent line is hanging down creating a place for liquid fuel to accumulate. The line on my Allegro is zip tied in several places to the filler pipe preventing this from happening.

Dieselclacker

DonBren · 08-21-2011, 06:55 PM

Thanks for the reply dieselclacker. I am curious as to the use of nylon versus rubber, is it more durable. I already purchased Gates rubber line but if the nylon line is a better choice I will purchase it instead. I did go to Lowes and noticed they had a plastic coated hose but don't know if that would be any better. I noticed you mentioned using a 1/4 OD line, was that a misprint or are you using that small of a line due to a space problem going through your vent line? As far as the vent line hanging down mine is a metal tube except for the 4 inch rubber hose right at the tank inlet so I don't think that would be the problem. I have learned to live with it, just reposition the fill nozzle until I find the right spot and fill slowly. Thanks again for the reply.

dieselclacker · 08-21-2011, 07:22 PM

I used the plastic line because it is easier to thread down the vent line and into the tank, and also it is more durable and smaller than 1/4 ID fuel line. Most fuel line has a liner that is compatable with the fuel that flows thru it, don't know how long the outside material on the fuel line would last if it were submerged in fuel all the time. The 1/4 OD is not a misprint, and it flows plenty for your generator. Look at the air lines that go to your front suspension air bags, that is the type of line you want.

Dieselclacker

Belgian · 08-21-2011, 10:06 PM

Don, I don't know what you have done to trace your fuel line from tank to gen, but just for your information. My Dolphin had a splice in the gas hose between the tank and the inner frame. What I suspect is it came from WH with a gas hose from the tank to the frame and National ran a hose from the frame to the generator. On mine there was a short piece of copper tubing stuck in both pieces of hose and two hose clamps. It was a bear to see let alone get to. I used a long screwdriver to secure the hose clamps and haven't had a problem since. Just a thought.

Steve

DriVer · 08-22-2011, 08:44 AM

Quote:

Originally Posted by Belgian

Don, I don't know what you have done to trace your fuel line from tank to gen, but just for your information. My Dolphin had a splice in the gas hose between the tank and the inner frame. What I suspect is it came from WH with a gas hose from the tank to the frame and National ran a hose from the frame to the generator. On mine there was a short piece of copper tubing stuck in both pieces of hose and two hose clamps. It was a bear to see let alone get to. I used a long screwdriver to secure the hose clamps and haven't had a problem since. Just a thought.

Steve back in those days the chassis would shop with what were called "Pony Tanks." The permanent fuel pump was located in the 2 to 3 gallon plastic pony tank which was mounted on top of the right side rail close to the engine.

It was up to the individual OEM to remove the pump, dismount the pony tank, install the fuel pump into the gas tank and supply the engine and generator set in the frame shop. There are probably as many different setups as there were manufactures out there. In recent years the fuel system was shipped complete (no pony tank) and the gen set feed was added at the time of the build.

DonBren · 08-23-2011, 04:45 AM

Steve, unfortunately I don't have the same setup, I traced from generator to top of tank, in fact replaced all but last 12 inches and that is where I suspect my problem is. Thanks DriVer for the bit of info pertaining to pony tank, did not know that.

txdutt · 08-23-2011, 09:13 PM

I'm having the same issue with my Onan, no gas to the carb. I verified the fuel filter wasn't clogged (changed it last year to the new style with the bypass fitting up top). I bought some new fuel line and will test the pump this weekend by disconnecting the main line from the gas tank & putting it into my lawn mower can to see if the pump will pull from that. I suspect the pump is bad as it's not pulling much of anything when I try to prime it with the existing fuel line disconnected to see what it's suction is like... know more this weekend!

DAN L · 08-24-2011, 02:40 AM

Quote:

Originally Posted by txdutt

I'm having the same issue with my Onan, no gas to the carb. I verified the fuel filter wasn't clogged (changed it last year to the new style with the bypass fitting up top). I bought some new fuel line and will test the pump this weekend by disconnecting the main line from the gas tank & putting it into my lawn mower can to see if the pump will pull from that. I suspect the pump is bad as it's not pulling much of anything when I try to prime it with the existing fuel line disconnected to see what it's suction is like... know more this weekend!

which onan genny do you have? you state that you ''changed THE fuel filter''.
my 5.5 marquis gold has 2 fuel filters, same part number. one is at the carburetor and the other is below the genny floor pan next to the fuel pump. i had to change them both. i had to cut the original clamps off (they were leaking) and replace the 1/4'' fuel line.

gbs2320 · 08-24-2011, 07:23 AM

The second filter at the carb has apparently been eliminated and replaced by an adapter. Mine still has that filter so I guess I need to replace it with the adapter at some point. http://forums.goodsamclub.com/index.cfm/fuseaction/thread/tid/25218976.cfm

txdutt · 08-24-2011, 07:38 PM

Quote:

Originally Posted by DAN L

which onan genny do you have? you state that you ''changed THE fuel filter''.
my 5.5 marquis gold has 2 fuel filters, same part number. one is at the carburetor and the other is below the genny floor pan next to the fuel pump. i had to change them both. i had to cut the original clamps off (they were leaking) and replace the 1/4'' fuel line.

marquis gold 5500 HGJAB model, searched on the forum and found a cheaper alternative to the Onan fuel pump that most auto parts stores stock--Airtex E8016S-it's about $40 less and is the same pump from what I've read...will find out this weekend if that's the problem

scoutmstr · 08-25-2011, 01:36 PM

There is a method for disconnecting the fuel pump lines before dropping the tank if yu have or can get access to the lnes from the top. Also be aware that on my coach the fuel lines were not fuel injection hose (I'm the original owner) See attached link for what I did.http://www.irv2.com/forums/f22/gas-t...nes-57339.html