Sitting on bombs? (CJ gas tanks)

I been reading this thead a couple of times lately and its time to chime in. I have the underseat tank in the '62 CJ5 with a small block Chevy in the frame rails. It gets on a good day after the tune up about 12.0 mpg, most of the time somewhere much lower. The 10 gallon tank is a pain!!!! I have 4.56 gears and can pass just about anything except a gas a station. The 33's have it turning 3000rpm at 60 mph, ouch! The tank I have has the original 4 cylinder sender, which has no vent. I have to rock the tank to get anything over 8.75 gallons in it. I tell people it's a Tupperware Jeep and I have to burp it. As for fumes I don't have any inside. The only problem I have was when I first got it the floor boards where hacked and with the Supertop opened where air would go out ie: bikini, off, or the tops of the doors off, I would get air drawn up through the firewall & floorpan and it would heat the tank and my legs to a few degrees below barbeque temps. That was my heater last year, open the windows and fry the feet. That is when I had to put a race car interior into it. The Aluminum panels have a heat shield attached and now there is no problem.

 

re: Courier 4x4

I've fond memories of that one. I put on a roll bar and big tires without cutting sheet metal and it looked GREAT like nothing else around (until Toyota came out with their stock 4x4). Of course, that ford 4 banger was incredibly SLOW! Momentum was the name of the game then!

 

My tank is poly and doesn't leak at the sender a bit. I do have fume issues with my hard top and doors on. The hard top doors cover the filler neck/cap. With a full tank it gets pretty fumeriferous Replacing the cap only seemed to help a little bit.

 

I once heard that a gas tank full of gas is less explosive than a tank 1/4 full, something about the fumes are what is so explosive. I don't know if thats correct, just sounds logical.

 

sounds correct to me.

 

2 quick underseat tank stories
Story #1:
jeepngems 70 stalled (stuck) slightly sidehill on sand dune at Pismo; carb flooded from angle; raw gas coming out open headers; crank engine over to snuff out flames;(common tactic); flames from open header meet dripping gas from underseat tank; jeepngem has wall of flame on drivers side; jeepngem grabs fire extinguisher on top of underseat tank; extinguishes fire while sitting in Jeep and Jeep is rolling backwards down dune; passenger sees flames, hits quick release belts and runs for his life; the passenger was me (at 14 years old ) ;jeepngem to NEVER again run with open headers
Story #2:
welder/fabricator installing cage/rollbar in my Jeep circa 1975; also welding up various holes from POs in top of body seam; he starts welding on top of seam near drivers side tank; wife is watching him as he proceeds along to drivers rear quarter panel; he reaches end of quarter panel when wife taps him on shoulder; he says WHAT?; she asks if that little blue flame is supposed to be coming out of the keyhole on the locking gas cap; he says NO and flame is extinguished ASAP; the flame had been there for about 5-10 minutes!
Moral of the story: better to be lucky than good!

 

Had a memory "jar after looking at the four door Ford. I owned several of those during those years and worked at Ford dealership for a short time back then. McRuff is correct the last year for in cab tanks was 72. Thre was a factory option if memory servs for the crew cab as an auxillary and I think on the super cab but not that I can rememberon the regular cab. As a matter of fact it was a big selling point in 73 an74 that it wasn't in the cab. Ibelieve on cab and chassis model it was available as an in cab option.

 

Wow Jim, tough stories. Lucky is right. How did that gas-cap flame not ignite the gas tank??

 

I believe The last ford pick up with an inside tank was built in april of 77. F 250 frames changed in april. before that the 250s had a 34 inch frame width, while the f100 and f150s had a 37 inch frame width. after april they all had 37 inch wide frames. I believe f 100s had frame mounted tanks as early as 1973. the f100 tanks are wider than the f250 frames. the feds problably mandated the tanks move on half tons at first. I sit on my gas tank every day in my 3B !

 

I almost forgot. all the 73 to april 77 f250 beds had the hole in the side for the rear tank. it was just plugged with a tin cap. If you ordered an aux tank on a 250 you got a frame mounted tank in front of the rear axle. also at one point, I dont remember the years, you could order a f250 without the in cab tank . you would get the under bed one only. then there was a rubber plug in the side of the cab. crew cabs back then were hand built in ontario from regular cabs, I believe, I dont know much about them.

 

guess there is only one person who knows the answer to that question
nobody recalls if the tank was full or not, just lucky I guess

 

i originally put this on the intro page but edited it out since it is really meant for here. so boyink dont worry about replying to this one too. i read your answer in hardtop's

my 69 is supposed to be here end of THIS week!!!


though the "happy little" thread on underseat vs. rearmounted fuel tanks has me concerned now. interesting since when i had a cj2 when i was 17 years old it never really bothered me. i figure that it's my usual "what if" uber-paranoid anxiety syndrome kicking in. i have never rolled a jeep cj or anyother and usually don't get into "extreme" 4x4 tho dont mind watching it. i 4x4 to relax and "meld" with my machine. as the saying goes "it's a jeep thing".

I remember the fuel running out of our family wagoneer filler neck in the 60's in moab and on the ore trails when i was a kid and it was a rear tank. in fact the smell of fuel, burning clutch and overheating brakes is still kinda nostalgic for me.

boyink i looked at the conversion site and how much of a fiddle was that job in a v6? have you had any probs after removing the rear brace with frame integrity?

 

Hippo: Remember, I have one of those "Jeep" locking gas caps. I took it all apart and replaced the gasket, but it still leaks out the key hole!

 

I have both driverside and passenger side bombs. It's fun going around a fast right hand corner and reaching out to feel the gas leaking past the cap! As far as fumes go, I like the smell of gas but not exhaust.....

 

alan, you asked what dual tanks under the seats look like -- I examined it closely today and it looks exactly like the driver's side tank, only a mirror copy. It looked totally stock to me.

Having driven the jeep about 150 miles now, I noticed a tendency for a lot of heat to radiate from the headers and mufflers into the interior of the Jeep -- sort of like a heat control stuck in the "hot" setting! LOL! I hope the engine appreciates the pre-heated gasoline being fed to it.