Have to sell my bike due to home repair issues

[pbaker27]

The front nipples on both petcocks are not connected to anything. And when I tried switching to the old plugs and back, they have been dry.

[natemoen]

Do you have the octy on still?

[GLoweVA]

If you don't have anything hooked to the front nipples on the petcocks then you won't have a prime position, and if the plugs are dry that indicates the cylinders aren't getting any gas.
If the fuel level in the tank is too low, then 'on' no fuel will flow, but 'reserve' will.
An easy check to see if fuel is flowing to the bowls it to loosen(not fully take off) the drain plug on the bottom of the carb bowl and see if you get fuel or not.

[pbaker27]

hmm, the only thing different I did was put a tube endcap on the left side front nipple. The petcocks on my bike, if I move the lever straight down is "On". I had it running just fine before the acct/plug swap out and putting on the cap on the one nipple. I couldn't get a cap on the other front nipple, in fact sliced up my finger pretty good trying, due to the clamp I was trying to use...fuel seemed to be pretty high in the tank, obviosly not a full tank, but if I open the cap and look in, I can see fuel.

[natemoen]

Do you have the octy on still?

Do you have the octy on still?

[pbaker27]

No Octy came with the bike....the front nipple on the left has a rubber cap on it I put on with a screw down clamp. The left back nipple has a hose that is connected to the carbs The right front nipple has nothing attached to it and the back right nipple has another hose connected to the carbs.

[CaptonZap]

Take the hoses off of the petcocks, as though you were going to take the tank off.
Get a piece of hose that fits over the smaller tube on the petcock, the one that went to the nipple on #2or3 carb boot, and long enough to get your mouth on the other end.
Put the petcock lever in the "on" position, and suck on the tube, like there was a milkshake on the other end.
Does gas come out the big tube on the petcock?
Try the other side.
Let us know the outcome.
CZ

[GLoweVA]

CZ, I think you may have hit it right on the head. He's got an XJ, so he should have the vaccum controlled petcocks. With nothing on the 'front' nipples (the vac control lines) then nothing should flow when in the 'on' position unless they're sucked on, or there's a lot of leak by.

Prime should work though.

[pbaker27]

Like I said, before I swapped out the plugs, and put the cap on the one nipple I had no issues getting it to start and switching it to the "ON' position. I try removing the one cap and see if it starts after that. Only problem is those two nipples leak gas then.

[jwhughes3]

If those front nipples are leaking gas then you need to rebuild the petcocks...they should be dry and sealed to allow vacuum applied to open the petcock.

John

[CaptonZap]

If those front nipples are leaking gas then you need to rebuild the petcocks...they should be dry and sealed to allow vacuum applied to open the petcock.

John

You got that right!
And check me if I'm wrong, but would not the hose connected from the petcock to the nipple be sucking gas out of the petcock, right into the intake tract, thereby running rich to the point of not running at all? CZ

[pbaker27]

ok, so i need to get petcock repair/rebuild kits for the xj. Once I rebuild both petcocks, what do I do to get the fuel system to work without having the Octi, since its a 79 engine/carb and the 82xj tank?

[GLoweVA]

ok, so i need to get petcock repair/rebuild kits for the xj. Once I rebuild both petcocks, what do I do to get the fuel system to work without having the Octi, since its a 79 engine/carb and the 82xj tank?

You'll need 2 vac lines to go from the carb boot nipples (usually #1 & #4) to attach to the front nipples on the petcocks. The petcock outlets (back ones) go to the carb fuel inlets. (on the 79 that would be the lower set, the upper ones are carb fuel vents that need to open to atmosphere.)

If you can, snap a pic of your tank/carb/petcock setup and post it up here so we can verify what we're talking about.

[GLoweVA]

WAIT A MINUTE!
He's got an 82XJ Tank, then it should have non vacuum controlled petcocks!
So the front nipple is the prime hole and the back nipple is the regular 'on' hole.
So he probably could get fuel out of the prime hole if the lever is in the correct position.
He should be able to blank off/plug the prime nipples and operate just fine on the 'on' nipples in either 'on' or 'reserve'.
He does need to make sure that all 4 of his carb boot nipples are capped too.
Having one of these caps off could have caused the high revving at idle.

[GLoweVA]

Here's a link to the XJ parts fiche:
http://www.ytcn.nl/archief/Archief/Y...XJ/XJ1100J.PDF