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Topic: 2002 320 fuel tank vent location (Read 948 times) previous topic - next topic

2002 320 fuel tank vent location

Well the plot thickens.
checked the fuel return line for the AquaHot.... hmmm blow on return hose and get blow back... remove the fuel filler cap and no blow back...
Wonder if it is a faulty cap(s) or.... I have a plugged fuel tank vent..... which would cause the AH pump to leak....
Wonder where they would hide such an animal?? Ideas anyone???
This is build 6036
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel

Re: 2002 320 fuel tank vent location

Reply #1 –
Don't know about your coach, but my '99 has one fuel tank vent and it vents the generator Aqua Hot and engine. If it was plugged it would effect your Cummins first.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: 2002 320 fuel tank vent location

Reply #2 –
Quote from: craneman –
Don't know about your coach, but my '99 has one fuel tank vent and it vents the generator Aqua Hot and engine. If it was plugged it would effect your Cummins first.
The fuel caps are a one way cap, ie: they will let air into the tank if there is a vacuum present, but will not let pressure out, hence why it  needs a separate tank vent..Just do not know where they would put the vent ie: near the fuel sender & curb fill neck or.. on the street side on the tank extension for the fuel fill. ( the tank on the street side is kinda goofy looking, and looks to be an "add on" with a large 2 1/2" connecting pipe (that the clamps block any way to remove the cover over the AquaHot tank.. go figger)
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel

Re: 2002 320 fuel tank vent location

Reply #3 –
These are the lines and fittings that are on the street side tank fill  extension.
The 1st pic shows the 3 fittings/hoses on top of the tank extension
Looking thru the fill neck into the tank I can see that the closest of the 3 has a dip tube and the other 2 seem to just be return lines or mebbe the far one with the whickerbill knob is a vent?( you can see it in the 2nd pic..black rubbery knob
the 2nd pic shows the fittings looking past the fill neck (back side of the 1st pic) .. the AquaHot return line is the blurry fitting to the right and just above the fill neck.
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel

Re: 2002 320 fuel tank vent location

Reply #4 –
Reply 15 shows my vent it is the galvanized knob on top of the tank.
Fuel lines
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: 2002 320 fuel tank vent location

Reply #5 –
opps!
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel

Re: 2002 320 fuel tank vent location

Reply #6 –
AHH HAA.......
That whickerbill I see looks like a galvanized add on vent???? What do you think?
It is laying on it's side, wonder if it is goobered up inside so it cannot vent?
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel

Re: 2002 320 fuel tank vent location

Reply #7 –
Mine was the same and I know it was original.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: 2002 320 fuel tank vent location

Reply #8 –
I don't think your tank vents out. I think there is a vent that lets air in.
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: 2002 320 fuel tank vent location

Reply #9 –
Quote from: stump –
I don't think your tank vents out. I think there is a vent that lets air in.
I checked both tank fill caps, they let balance air into the tank but do not let pressure air out, think that is a safety feature , prevents fuel from leaking out of the tank (when not level/on a side hill).. so gotta have a vent somewhere.
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel

Re: 2002 320 fuel tank vent location

Reply #10 –
Not necessarily a vent, probably a pressure relief, also probably the galvanized part. The fuel recirculates from all sources. engine, AH and generator. Having the tank under low pressure wouldn't cause a problem. All of the cars now have sealed gas tanks that have pressure. 
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: 2002 320 fuel tank vent location

Reply #11 –
Quote from: craneman –
Not necessarily a vent, probably a pressure relief, also probably the galvanized part. The fuel recirculates from all sources. engine, AH and generator. Having the tank under low pressure wouldn't cause a problem. All of the cars now have sealed gas tanks that have pressure. 
Except the Aquahot , the fuel pump  is not happy with any back pressure against the fuel return line or so Roger says.. but will chase down the tank vent that should be attached to the rear upper bulkhead, or so I gather.. might have a mud dauber issue. Just trying to chase down all possibilities.
The fuel tank looks to be a main tank and another smaller tank that is overlapping the main tank.. fuel level looks to be "balanced" by a 2.5 inch or so  SS pipe.
Just did a down and dirty check of the lines going into the street side tank, The fuel return for the Cummins & the Gen set both return to the smaller street side tank, so I think that the farthest hose from the fuel filler cap is the tank vent.....

I will be closing this thread out if the AquaHot continues to run without leaking (fuel cap removed to insure no back pressure)
'02 40' U320t  4010WTFS Build 6036 1 slide
Motorcade # 17841
SKP 151920
Retired truck driver
 5 million miler
Still have itchy feet for travel