Slow gas filling problem on 88 YJ

[swanny71]

This is apparently a common problem with the YJ's. I have the 20 gal tank. I've found if I insert the nozzle so that the tail end of the handle is at 3 o'clock, it fills the best, but still very slow -- not nearly as fast as the first automatic hold notch on most all pumps. I have no leaks. Do I need to replace the vent line? Is there a test to see if that line is unclogged? I believe this has a closed venting system along with the charcoal canister, could the canister be clogged to cause this problem? Any help appreciated.

 

[machoheadgames]

The plastic 20 gallon was used in all years. Personally I can't say I've ever heard of slow gas filling being an issue. It was an issue on later TJs but I can't think of anything on a YJ that would even cause it to be slow. the YJ has a large vent tube that is there to allow the space taken up by the fuel to escape as you fill...unless that is clogged somehow but that's like a 1" hose, I don't see how it would be. The excess pressure does vent to the canister, but I don't think a canister problem can cause issues at the gas station because that should be all related to the large fill and vent hoses. May be worth dropping the tank to take a closer look anywho, I have not ever had this issue.

Are you overflowing if you let the gas station go too fast?

 

[Flyer58]

I converted my 15 gallon tank by cutting the vent line. In both cases there was never a problem filling the tank quickly but now with the vent tube cut shorter the tank will over flow just as the handle shuts off and spills gas. If I pump in the last few gallons it's ok.

 

[cas]

Not real familiar with the 20 gallon tanks, so I don't know how much room there is to work. Might want to unhook both line from the fill and "snake" them with something to make sure they're clear. (knew a guy years ago with a Ford Ranger with similar issues, turned out to be a small dry gas bottle cap down in the fill pipe)

 

[swanny71]

Thanks all for the suggestions. Upon closer attention it appears to be a fill problem - which I attributed to a venting problem. I just fill it carefully at a slow rate and it works. When/if I have another tank problem, I'll pull the tank to get a better look. Or I'll try to snake the lines - my son has a cable video system, might try that.

 

[T-Rex Jeepster]

Not real familiar with the 20 gallon tanks, so I don't know how much room there is to work. Might want to unhook both line from the fill and "snake" them with something to make sure they're clear. (knew a guy years ago with a Ford Ranger with similar issues, turned out to be a small dry gas bottle cap down in the fill pipe)

Here's the deal.....Same tank on ALL models, But someone on high figured out that if you take a vent tube and shove it down to the fifteen gallon level, You can then sell YJ's with a 20Gal option for a few bucks more I removed the vent tube and sawed it off just
past the port for it in the tank and got a 20 gal capacity for the price of some flesh off the back of my left hand, Because I refuse to drop a tank unless it has to be replaced. And once thats done...You can then position the pump handle straight up and down in the fuel port and go full blast on the lock without interruption ie. "Bottle Feed"

 

[machoheadgames]

Here's the deal.....Same tank on ALL models, But someone on high figured out that if you take a vent tube and shove it down to the fifteen gallon level, You can then sell YJ's with a 20Gal option for a few bucks more I removed the vent tube and sawed it off just
past the port for it in the tank and got a 20 gal capacity for the price of some flesh off the back of my left hand, Because I refuse to drop a tank unless it has to be replaced.

Same tank 91-95, different tanks 87-90. 87-90 used a 14.5 gallon metal tank and a 20 gallon plastic. You got the full capacity if you had an 87-90 plastic. Just clarifying because it confuses a lot of people when they can’t figure out they have in their 87-90.

 

[T-Rex Jeepster]

Same tank 91-95, different tanks 87-90. 87-90 used a 14.5 gallon metal tank and a 20 gallon plastic. You got the full capacity if you had an 87-90 plastic. Just clarifying because it confuses a lot of people when they can’t figure out they have in their 87-90.

 

[swanny71]

Mine's definitely 20 gallon, I've put in 18+ gallons a few times. Haven't tapped on the tank to verify plastic or metal. The vent hose length isn't probably the issue since it slow fills when it's near empty all the way up.

 

[machoheadgames]

Mine's definitely 20 gallon, I've put in 18+ gallons a few times. Haven't tapped on the tank to verify plastic or metal. The vent hose length isn't probably the issue since it slow fills when it's near empty all the way up.

Yeah if you can get in 18 then you definitely have the plastic tank with no limits.

The slow fill issue wouldn’t be an issue of vent tube length but could be due to a clog of either the fill or the vent.

 

[swanny71]

In the interest of helping others, I discovered my slow gas fill problem. On a hunch, I disconnected the vent line from the gas tank to the charcoal canister (at the canister), then proceeded to fill the tank. I was able to fill it at ALL SPEEDS with no shutting off of the nozzle at any time. This is the very first time in 3 years that I could do that, very pleasantly surprised. Used the same pump at the same station as well. At home, before I went to the gas station, I disconnected that line and put a longer test line on that canister port, then I blew into it, there was some resistance but definitely not plugged solid. So I wasn't expecting the results I got. I plan to rebuild my canister per a YouTube video where a guy cut the plastic canister in half along the mounting clamp area, then cut new foam filters from black, open cell foam and filled with new charcoal pellets (from an aquarium store), then plastic welded the seam back up. Evidently new canisters aren't available anymore, or are pretty pricey; but I'll check first.