hey ouray guys!!??

[toolman]

say you guys i am writing you guys here because your the ones that know. i live in loveland and am thinking of comming next year to join the fun, but have a few questions. first i have been sorta high in elev. maybe 10,500 but haven't experienced vapor lock. i have just the stock fuel pump and 2 barel carb on my 70 wag (link below) am i going to have problems? and a cheap way to fix it? also at elev. i have a problem with preasure in the gas tank. going up an incline (with a tank over 1/2 full) gas pores out the cap. now my jeep has no charcole canister. it just has a too and from line to the fuel pump. the gas comes out threw the vent in the cap and out the four holes on the outside.and since you guys ride at high elev. i thought maybe you or someone you know has run into this.. thanks a million smile.gif :D

[toolman]

try this link the other is messed up.

[gwinn]

Hey toolman, If your fuel is boiling in the tank (as mine did in Ouray 2003) it will be a problem. I had the Holley Pro-Jection unit and above 11,000 feet nothing but vapor got to the throttle body. I blamed it on the location of my electric fuel pump and the fact that I have a very hot running over-built engine. I will be moving my fuel lines and pump to the outside of the frame rail for better heat transfer before going back to Ouray in 2005. Hope to see ya there! smile.gif

[Don S]

Originally posted by toolman:
am i going to have problems? and a cheap way to fix it? also at elev. i have a problem with preasure in the gas tank. going up an incline (with a tank over 1/2 full) gas pores out the cap. smile.gif :D ..
toolman:

… Not every one has a vapor lock problem. But here is a link so you can read up about it.
link> VAPOR LOCK 101 (http://groups.msn.com/JEEPTECH101/jeeptech.msnw)

... The fuel cap on a 1981 FSJ (and probably most models) is semi-vented. The vent is normally closed but the vent will open with 0.75 to 1.5 psi or a vacuum of 1.1 to 1.8 inches. These stock caps will not allow a large amount of gasoline to leak out when they are in good condition.
Gasoline has a tendency to expand and vaporize quite a bit as its temperature rises.

... The temperature of gasoline in an under ground storage tank would be somewhere around 67 degrees F. The addition of summer outdoor temperature plus the heat in the pavement and the heat of the exhaust system can expand the gasoline in a ‘full tank’ enough to cause an over follow.

... Check the fuel cap be cause it may not be properly vented. Sometimes the POs change the caps and put the wrong kind on. The vent protects the tank and the engine from fuel starvation.

...The fuel cap on my '76 and my 1981 FSJ is vented. Get one at a junk yard and test it orally.

Have a good one ;) and CUL Don S..

[ October 10, 2004, 09:50 PM: Message edited by: Don S ]

[Heimeken]

Toolman, I think aside from the 101 link above. The main thing to make sure is that your rig does not run hot to begin with. In higher elevations the engine will run hotter then your normal. So make sure your fan , water pump and radiator are doing their job and that the transmission cooling is working too. Although my rig is heavily modified, the fuel delivery is all stock and no charcoal canister either.

[fulsizjeep]

Toolman - One of the things I did to Krista's 77 Wag was change out the fuel filler neck from a newer model. Up until about 78 or 79, the vent line was a metal tube that is actually molded to fit inside the left rear fender well. It turns and goes inside the vehicle above the fender well where another rubber hose is attached. So, you have a rubber hose from tank to metal tube, then tube goes inside and another rubber hose to attach to filler vent. You have to take the uphosltry panel off left side in back to get to that section. This original design has so many bends and is so long that it doesn't vent worth crapola. I pulled a filler tube off an 81 Waggy which has a vent tube that exits through the bottom of the body at the same place as the filler tube. This required minor cutting in the metal to accomodate the second tube. I also had the seal from the 81 to fit there. It looks stock this way. From there, I ran a 5/8 hose directly to the tank. This path is shorter and vents better. Pretty sure the original vent hose is designed for 1/2 hose. I am kinda rambling here and hope this makes sense... ;)

Now, she still doesn't vent as well as the 88 GW, but spews far less than before.

[toolman]

yea i have parked before up in the mountains after i noticed that i was leaking gas. slowly opened the cap letting out all the preassure, then while sitting there the gas was burping and shooting out the vent hose on the right side where it comes back to the main line. now that got gas up there but just some. the vent hose really is only for venting while filling your gas tank right. it does't let preassure out when the caps on, because its all in a clossed circuit. my gas cap has been dropped in the past and has a dent in it so that can mess up the calibration. so i am going to try to find one in better shape and see if that works better.none of my lines are hot so i don't think that heat is the culprit. so ?????? i'll try the gas cap first(easyer fix)

[LRRH]

toolman,

i went up to 13000 with my 70 and didn't have ANY vaporlock problems. at the time my fuel pump was 1 year old(stock replacement) and I leaked a little gas out of the cap but I have a lcoking vented cap. CHeck you vent lines and you should be fine. My wag does always run cool though. =)