'79 CJ5 gasline question.

Hi all,

it seems that if my '79 CJ5 is sitting for a while that the gas
runs through the line back to the tank.

That means that after it has been sitting for a while. I have to crank
it for a while before it starts. (if it sits for a day or so.. I have
to crank it quite a bit. If it sits there for an hour or 2 there's no
problem

I replaced all the hoses.

How does the gascap work ? is it supposed to seal the gastank,
or doesn't it matter ? The gascap I have is probably the original.


thanks,

Ron

That usually happens because the gas filter is in upside down. The
filter has two outlets, the center outlet leads to the carb and the
'top' one leads to the return line. If the return line isn't at the
top, gas will syphon back to the tank air locking the line and they are
real buggers to start up.

There also is a valve on the fuel pump likely to stop backflow. You
could first make sure the filter is right, then take the line off the
pump intake to see if the gas all comes out.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)


Ron Croonenberg wrote:
>
> Hi all,
>
> it seems that if my '79 CJ5 is sitting for a while that the gas
> runs through the line back to the tank.
>
> That means that after it has been sitting for a while. I have to crank
> it for a while before it starts. (if it sits for a day or so.. I have
> to crank it quite a bit. If it sits there for an hour or 2 there's no
> problem
>
> I replaced all the hoses.
>
> How does the gascap work ? is it supposed to seal the gastank,
> or doesn't it matter ? The gascap I have is probably the original.
>
> thanks,
>
> Ron

Ok, let me check that.

It always had that problem, also when I replaced the fuel pump.
I can check to see if the filter is upside down or not.

If it is the fuelfilter doing that, are there any better ones ? How do I
know I have the correct one ? (Is there a pic of one somewhere ?

Is there a "everything you wanted to ask about your CJ's fuel lines but
were afraid to ask" page somewhere ?



> That usually happens because the gas filter is in upside down. The
> filter has two outlets, the center outlet leads to the carb and the
> 'top' one leads to the return line. If the return line isn't at the
> top, gas will syphon back to the tank air locking the line and they are
> real buggers to start up.
>
> There also is a valve on the fuel pump likely to stop backflow. You
> could first make sure the filter is right, then take the line off the
> pump intake to see if the gas all comes out.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> (More Off Road album links at bottom of the view page)
>
>
> Ron Croonenberg wrote:
>
>>Hi all,
>>
>>it seems that if my '79 CJ5 is sitting for a while that the gas
>>runs through the line back to the tank.
>>
>>That means that after it has been sitting for a while. I have to crank
>>it for a while before it starts. (if it sits for a day or so.. I have
>>to crank it quite a bit. If it sits there for an hour or 2 there's no
>>problem
>>
>>I replaced all the hoses.
>>
>>How does the gascap work ? is it supposed to seal the gastank,
>>or doesn't it matter ? The gascap I have is probably the original.
>>
>>thanks,
>>
>>Ron

The parts stores around here all carry the CJ gas filter. The YJ up to
91 uses the same one. Once it is in place it won't rotate unless
bumped, but it 'is' easy to rotate if you are mucking about with the
carb.

I find the Haynes CJ manual to be a very good one. It covers pretty
much everything accurately.

The owners manual even mentions the right way to install the fuel
filter.

Mike

Ron Croonenberg wrote:
>
> Ok, let me check that.
>
> It always had that problem, also when I replaced the fuel pump.
> I can check to see if the filter is upside down or not.
>
> If it is the fuelfilter doing that, are there any better ones ? How do I
> know I have the correct one ? (Is there a pic of one somewhere ?
>
> Is there a "everything you wanted to ask about your CJ's fuel lines but
> were afraid to ask" page somewhere ?
>
> > That usually happens because the gas filter is in upside down. The
> > filter has two outlets, the center outlet leads to the carb and the
> > 'top' one leads to the return line. If the return line isn't at the
> > top, gas will syphon back to the tank air locking the line and they are
> > real buggers to start up.
> >
> > There also is a valve on the fuel pump likely to stop backflow. You
> > could first make sure the filter is right, then take the line off the
> > pump intake to see if the gas all comes out.
> >
> > Mike
> > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> > 88 Cherokee 235 BFG AT's
> > Canadian Off Road Trips Photos: Non members can still view!
> > Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> > (More Off Road album links at bottom of the view page)
> >
> >
> > Ron Croonenberg wrote:
> >
> >>Hi all,
> >>
> >>it seems that if my '79 CJ5 is sitting for a while that the gas
> >>runs through the line back to the tank.
> >>
> >>That means that after it has been sitting for a while. I have to crank
> >>it for a while before it starts. (if it sits for a day or so.. I have
> >>to crank it quite a bit. If it sits there for an hour or 2 there's no
> >>problem
> >>
> >>I replaced all the hoses.
> >>
> >>How does the gascap work ? is it supposed to seal the gastank,
> >>or doesn't it matter ? The gascap I have is probably the original.
> >>
> >>thanks,
> >>
> >>Ron

I just checked the CJ the off center outlet is on top
I don't have the original carb anymore I have that weber one

Mike Romain wrote:

> The parts stores around here all carry the CJ gas filter. The YJ up to
> 91 uses the same one. Once it is in place it won't rotate unless
> bumped, but it 'is' easy to rotate if you are mucking about with the
> carb.
>
> I find the Haynes CJ manual to be a very good one. It covers pretty
> much everything accurately.
>
> The owners manual even mentions the right way to install the fuel
> filter.
>
> Mike
>
> Ron Croonenberg wrote:
>
>>Ok, let me check that.
>>
>>It always had that problem, also when I replaced the fuel pump.
>>I can check to see if the filter is upside down or not.
>>
>>If it is the fuelfilter doing that, are there any better ones ? How do I
>>know I have the correct one ? (Is there a pic of one somewhere ?
>>
>>Is there a "everything you wanted to ask about your CJ's fuel lines but
>>were afraid to ask" page somewhere ?
>>
>>
>>>That usually happens because the gas filter is in upside down. The
>>>filter has two outlets, the center outlet leads to the carb and the
>>>'top' one leads to the return line. If the return line isn't at the
>>>top, gas will syphon back to the tank air locking the line and they are
>>>real buggers to start up.
>>>
>>>There also is a valve on the fuel pump likely to stop backflow. You
>>>could first make sure the filter is right, then take the line off the
>>>pump intake to see if the gas all comes out.
>>>
>>>Mike
>>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
>>>88 Cherokee 235 BFG AT's
>>>Canadian Off Road Trips Photos: Non members can still view!
>>>Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
>>>(More Off Road album links at bottom of the view page)
>>>
>>>
>>>Ron Croonenberg wrote:
>>>
>>>
>>>>Hi all,
>>>>
>>>>it seems that if my '79 CJ5 is sitting for a while that the gas
>>>>runs through the line back to the tank.
>>>>
>>>>That means that after it has been sitting for a while. I have to crank
>>>>it for a while before it starts. (if it sits for a day or so.. I have
>>>>to crank it quite a bit. If it sits there for an hour or 2 there's no
>>>>problem
>>>>
>>>>I replaced all the hoses.
>>>>
>>>>How does the gascap work ? is it supposed to seal the gastank,
>>>>or doesn't it matter ? The gascap I have is probably the original.
>>>>
>>>>thanks,
>>>>
>>>>Ron

The carb doesn't matter unless it won't run at the CJ carb's pressure
which is a different problem. It is just physics with the gas lines.
If the return is up top, gas won't syphon.

There was a thread back a while ago about the pressure that filter is
set for. Some place around 5 psi I think. It is set by the hole size
in the return line outlet. Lower pressure could be had by drilling out
the blocking plate.

Mike

Ron Croonenberg wrote:
>
> I just checked the CJ the off center outlet is on top
> I don't have the original carb anymore I have that weber one
>
> Mike Romain wrote:
>
> > The parts stores around here all carry the CJ gas filter. The YJ up to
> > 91 uses the same one. Once it is in place it won't rotate unless
> > bumped, but it 'is' easy to rotate if you are mucking about with the
> > carb.
> >
> > I find the Haynes CJ manual to be a very good one. It covers pretty
> > much everything accurately.
> >
> > The owners manual even mentions the right way to install the fuel
> > filter.
> >
> > Mike
> >
> > Ron Croonenberg wrote:
> >
> >>Ok, let me check that.
> >>
> >>It always had that problem, also when I replaced the fuel pump.
> >>I can check to see if the filter is upside down or not.
> >>
> >>If it is the fuelfilter doing that, are there any better ones ? How do I
> >>know I have the correct one ? (Is there a pic of one somewhere ?
> >>
> >>Is there a "everything you wanted to ask about your CJ's fuel lines but
> >>were afraid to ask" page somewhere ?
> >>
> >>
> >>>That usually happens because the gas filter is in upside down. The
> >>>filter has two outlets, the center outlet leads to the carb and the
> >>>'top' one leads to the return line. If the return line isn't at the
> >>>top, gas will syphon back to the tank air locking the line and they are
> >>>real buggers to start up.
> >>>
> >>>There also is a valve on the fuel pump likely to stop backflow. You
> >>>could first make sure the filter is right, then take the line off the
> >>>pump intake to see if the gas all comes out.
> >>>
> >>>Mike
> >>>86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> >>>88 Cherokee 235 BFG AT's
> >>>Canadian Off Road Trips Photos: Non members can still view!
> >>>Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> >>>(More Off Road album links at bottom of the view page)
> >>>
> >>>
> >>>Ron Croonenberg wrote:
> >>>
> >>>
> >>>>Hi all,
> >>>>
> >>>>it seems that if my '79 CJ5 is sitting for a while that the gas
> >>>>runs through the line back to the tank.
> >>>>
> >>>>That means that after it has been sitting for a while. I have to crank
> >>>>it for a while before it starts. (if it sits for a day or so.. I have
> >>>>to crank it quite a bit. If it sits there for an hour or 2 there's no
> >>>>problem
> >>>>
> >>>>I replaced all the hoses.
> >>>>
> >>>>How does the gascap work ? is it supposed to seal the gastank,
> >>>>or doesn't it matter ? The gascap I have is probably the original.
> >>>>
> >>>>thanks,
> >>>>
> >>>>Ron