| Gas Tanks Not Communicating [message #99906] |
Wed, 15 September 2010 12:26  |
jcurran
Messages: 52
Registered: May 2009
Karma: 0
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Folks,
I've got a couple of issues with my fuel system:
First, the forward and aft tanks don't seem to be talking very well. On fill-up, the primary fills and the secondary catches up very slowly - like 20 minutes after I leave the gas station. So this means more fuel stops .
A second problem is that if the coach sits for a week or more, it will not start (fuel does not reach the carb). I have changed and checked the filters. The way I have gotten it started is to disconnect the fuel line at the mechanical pump, blow into it (thinking I am clearing the socks) and then follow that with a hand pump to pull fuel forward out of the tank. Once I have fuel at the front of the coach, I reconnect the line to the pump and we have ignition and normal operation.
Extra info - the lines and pickups are original, AFAIK. Just before I noticed this problem (at the beginning of a 1600-mile roundtrip), I had a fuel burp event from the separator valve in the rear wheel-well during a fill-up. Aside from never getting a true fill-up, the coach ran great.
I'm planning to take down the tanks and work the issues but I wanted to know if anyone had any idea what I was in for so I could be prepared.
Thanks for any help,
Jim
Jim Curran
1976 Palm Beach
Alexandria, OH
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| Re: Gas Tanks Not Communicating [message #99911 is a reply to message #99908] |
Wed, 15 September 2010 13:01  |
Keith V
Messages: 2337
Registered: March 2008
Location: Mounds View,MN
Karma: 0
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Senior Member |
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| WD0AFQ wrote on Wed, 15 September 2010 12:38 |
Jim, while it is tough to get both tanks full it can be done and should not take as long as your's. I suspect a venting problem. You will fix that when you change out all of the lines. I did a photo search for the "tank dropping" and studied them for a week before I dropped my tanks. I would call and get both filler tubes before dropping them. The ones that go from the filling line to each tank. One is elbow and other is straight. They ain't cheap but you need them while you have the tanks down.
I am no mechanic but have done my tanks. There will be others, with a lot more information than I have offered you, shortly. My next "dropping" will include in tank fuel pumps for my Holley TBI.
Dan
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I just did mine, it's a job alright. I ran steel lines as much as I could. I tried using brass compression couplings from the tank to the steel line but I didn't like the way it had to flex when putting the tank in place. So I used a short piece of fuel hose.
Keith Vasilakes
Mounds View. MN
75 ex Royale GMC
ask me about MicroLevel
Cell, 763-732-3419
My427v8@hotmail.com
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| Re: Gas Tanks Not Communicating [message #99913 is a reply to message #99906] |
Wed, 15 September 2010 13:25 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
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Senior Member |
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| jcurran wrote on Wed, 15 September 2010 11:26 |
Folks,
I've got a couple of issues with my fuel system:
First, the forward and aft tanks don't seem to be talking very well. On fill-up, the primary fills and the secondary catches up very slowly - like 20 minutes after I leave the gas station. So this means more fuel stops .
A second problem is that if the coach sits for a week or more, it will not start (fuel does not reach the carb). I have changed and checked the filters. The way I have gotten it started is to disconnect the fuel line at the mechanical pump, blow into it (thinking I am clearing the socks) and then follow that with a hand pump to pull fuel forward out of the tank. Once I have fuel at the front of the coach, I reconnect the line to the pump and we have ignition and normal operation.
Extra info - the lines and pickups are original, AFAIK. Just before I noticed this problem (at the beginning of a 1600-mile roundtrip), I had a fuel burp event from the separator valve in the rear wheel-well during a fill-up. Aside from never getting a true fill-up, the coach ran great.
I'm planning to take down the tanks and work the issues but I wanted to know if anyone had any idea what I was in for so I could be prepared.
Thanks for any help,
Jim
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Jim--what do you mean by a burp event at the separator--did fuel escape? If so, the separator is cracked. As far as not getting the fuel pump to prime, it could be a pinched line between the body and frame due to missing body pads. It could also be plugged pick up socks. To really clear those or blow them off, I would first remove the filler cap, and disconnect the two input lines coming into the switch-over valve and blow back into each of them at that point.
Bob de Kruyff
78 Eleganza
Chandler, AZ
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| Re: Gas Tanks Not Communicating [message #99951 is a reply to message #99925] |
Wed, 15 September 2010 16:20 |
spiffycar
Messages: 133
Registered: May 2010
Location: Brook Park ,Ohio
Karma: 1
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Senior Member |
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Had similar problems with mine a while back as well.Changed over to an electric pump after the fuel selector valve & eliminated the mechanical pump altogether. While doing this I found that the hose to from the tank selector to the mechanical pump had several "pin holes" it.These were found once the line was pressurized from the new pump. It never showed any signs of leaking before this ,so it might a good idea to check for them. May be why you are loosing the prime on the mechanical pump to begin with.
OR just go ahead and replace that fuel line for now anyways & see what happens before you go spending a bunch of money on new pumps and the like.
Paul W L
76 Daytona Beach! ( EX-Palm Beach )
Cleveland,OH
& Current Card Carrying Pull A Part VIP Member
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| Re: Gas Tanks Not Communicating [message #99956 is a reply to message #99951] |
Wed, 15 September 2010 17:13 |
Bob de Kruyff
Messages: 4260
Registered: January 2004
Location: Chandler, AZ
Karma: 1
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Senior Member |
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| spiffycar wrote on Wed, 15 September 2010 15:20 |
Had similar problems with mine a while back as well.Changed over to an electric pump after the fuel selector valve & eliminated the mechanical pump altogether. While doing this I found that the hose to from the tank selector to the mechanical pump had several "pin holes" it.These were found once the line was pressurized from the new pump. It never showed any signs of leaking before this ,so it might a good idea to check for them. May be why you are loosing the prime on the mechanical pump to begin with.
OR just go ahead and replace that fuel line for now anyways & see what happens before you go spending a bunch of money on new pumps and the like.
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Funny you should say that. Apparently my previous electric pump wasn't working and I thought I had what appeared to be vapor lock. When I replaced the pump, I realized that I had pin hole leaks in the delivery line. When I repaired those, the pump hasn't been needed at all so far this summer.
Bob de Kruyff
78 Eleganza
Chandler, AZ
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