Mystery valve help needed
 

My son's recently acquired '90 YJ (4 cylinder, 5-speed) has been
smelling of gasoline, and a little checking revealed a broken valve
tucked up inside the body behind the right rear wheel well. I have a
factory service manual and have studied it carefully but can't figure
out the purpose of this valve. It looks to be a check valve, on one
side there's a line going to the fuel tank and on the other side
there's a vacuum hose that runs up to the engine compartment. I
thought mabe it was a rollover valve but according to the manual those
are supposed to be attached the fuel tank.

What do I ask for when I go to the dealer to get a replacement?

Miguel did pass the time by typing:
> My son's recently acquired '90 YJ (4 cylinder, 5-speed) has been
> smelling of gasoline, and a little checking revealed a broken valve
> tucked up inside the body behind the right rear wheel well. I have a
> factory service manual and have studied it carefully but can't figure
> out the purpose of this valve. It looks to be a check valve, on one
> side there's a line going to the fuel tank and on the other side
> there's a vacuum hose that runs up to the engine compartment. I
> thought mabe it was a rollover valve but according to the manual those
> are supposed to be attached the fuel tank.
>
> What do I ask for when I go to the dealer to get a replacement?

From what you describe that sounds like the line that vents the fuel
tank to the charcoal canister up front. It's a check valve that allows
fuel vapor to run up and get trapped in the canister. The vapors are
then sucked back into the intake when the engine starts.

Part of the emissions control stuff.

--
DougW

Could be your gas tank roll-over check valve. Some attached to the
frame cross member just forward of the tank.
God Bless America, ßill O|||||||O
http://www.billhughes.com/

Miguel wrote:
>
> My son's recently acquired '90 YJ (4 cylinder, 5-speed) has been
> smelling of gasoline, and a little checking revealed a broken valve
> tucked up inside the body behind the right rear wheel well. I have a
> factory service manual and have studied it carefully but can't figure
> out the purpose of this valve. It looks to be a check valve, on one
> side there's a line going to the fuel tank and on the other side
> there's a vacuum hose that runs up to the engine compartment. I
> thought mabe it was a rollover valve but according to the manual those
> are supposed to be attached the fuel tank.
>
> What do I ask for when I go to the dealer to get a replacement?

I missed the original post, but that is a check valve for the emissions
canister. I have seen those leak fumes before.

I am not sure about the books for those things... The book for my CJ
shows the valve in line like yours, but mine 'is' on/in the tank and the
only YJ one I have seen was up under the wheel well like yours.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

DougW wrote:
>
> Miguel did pass the time by typing:
> > My son's recently acquired '90 YJ (4 cylinder, 5-speed) has been
> > smelling of gasoline, and a little checking revealed a broken valve
> > tucked up inside the body behind the right rear wheel well. I have a
> > factory service manual and have studied it carefully but can't figure
> > out the purpose of this valve. It looks to be a check valve, on one
> > side there's a line going to the fuel tank and on the other side
> > there's a vacuum hose that runs up to the engine compartment. I
> > thought mabe it was a rollover valve but according to the manual those
> > are supposed to be attached the fuel tank.
> >
> > What do I ask for when I go to the dealer to get a replacement?
>
> From what you describe that sounds like the line that vents the fuel
> tank to the charcoal canister up front. It's a check valve that allows
> fuel vapor to run up and get trapped in the canister. The vapors are
> then sucked back into the intake when the engine starts.
>
> Part of the emissions control stuff.
>
> --
> DougW

Take the valve off and take it to the store with you. Drop it on the counter
and say, "I need one of these." The guy will disappear to the back of the
store for a few minutes, when he returns he will have a part. Make sure the
part looks like the one you brought into the store. Take the part home and
hook it up.

Have a beer and admire your repair.





"Miguel" > wrote in message
...
> My son's recently acquired '90 YJ (4 cylinder, 5-speed) has been
> smelling of gasoline, and a little checking revealed a broken valve
> tucked up inside the body behind the right rear wheel well. I have a
> factory service manual and have studied it carefully but can't figure
> out the purpose of this valve. It looks to be a check valve, on one
> side there's a line going to the fuel tank and on the other side
> there's a vacuum hose that runs up to the engine compartment. I
> thought mabe it was a rollover valve but according to the manual those
> are supposed to be attached the fuel tank.
>
> What do I ask for when I go to the dealer to get a replacement?
>
>

i want to go to that parts store! whenever i stop in for anything the
guy has to know the make, model, engine size, mothers maiden name and
shoe size before he can look up the wrong part on his computer.

wall

It's a Doohicky
God Bless America, ßill O|||||||O
http://www.billhughes.com/

Jeff Strickland wrote:
>
> Take the valve off and take it to the store with you. Drop it on the counter
> and say, "I need one of these." The guy will disappear to the back of the
> store for a few minutes, when he returns he will have a part. Make sure the
> part looks like the one you brought into the store. Take the part home and
> hook it up.
>
> Have a beer and admire your repair.

Number twenty would be the roll-over vent valve:
http://www.billhughes.com/YJfuelLines.pdf

"L.W.(ßill) Hughes III" wrote:
>
> Could be your gas tank roll-over check valve. Some attached to the
> frame cross member just forward of the tank.
> God Bless America, ßill O|||||||O
>

As long as the doohicky they give you looks like the doohicky you carried
in, then all is well.




"L.W. (ßill) Hughes III" > wrote in message
...
> It's a Doohicky
> God Bless America, ßill O|||||||O
> http://www.billhughes.com/
>
> Jeff Strickland wrote:
> >
> > Take the valve off and take it to the store with you. Drop it on the
counter
> > and say, "I need one of these." The guy will disappear to the back of
the
> > store for a few minutes, when he returns he will have a part. Make sure
the
> > part looks like the one you brought into the store. Take the part home
and
> > hook it up.
> >
> > Have a beer and admire your repair.

My parts guy at NAPA builds custom cars, when he see me coming, he knows the
book is at best a starting point. Amazingly, when I bring in the various
assorted doohickies - Bill's word - my parts guy usually knows what it is.
He needs the make and model just to confirm his suspicions.

My NAPA store is a Commerical Truck center, or some such thing. The guys in
there are better than your average parts guys. If they come out from the
back with the wrong part, they can normally cross reference whatever I
walked in with and I leave with a part that works.




"wallster" > wrote in message
ups.com...
> i want to go to that parts store! whenever i stop in for anything the
> guy has to know the make, model, engine size, mothers maiden name and
> shoe size before he can look up the wrong part on his computer.
>
> wall
>