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[DobaMark]

The choke has nothing to do woth vapor lock.  If vapor lock occurs, it's because the fuel pump is trying to move fuel vapor instead of liquid fuel.  Somethign causes the fuel in the fuel line to vaporize.  One of Chrysler's fixes was to install a small electronic fuel pump near the tank where fuel should be cooler.  Pushing the fuel forward eliminted the problem of the mechanical pump stumbling because of trying to suck vapor through the system.

Next time the car dies, pull the air cleaner.  Look and verify the choke is open.  Then remove the air cleaner.  Move the throttle linkage by hand and see if you get a squirt of gas inside the carb.  If not, you may be starving for gas.  Or you may see signs the carb is flooding which can happen when older carb floats are no good.

The bad news is now carberators are more likely to need work because of the junk gasoline but fewer people know how to work on them.

If it's starving for gas, then it then comes down to vapor lock, line blockage, etc.
I had a 1979 Volare slant 6 that gave me fits.  It usually ran great, though sometimes it would simply refuse to start or not have the power it should. There was a slight hole in one of the rubber fuel lines near the tank that sometimes cause it to suck air instead of gas.

[Dippy.org]

[Ice Cold]

What Mark says..have to see if it's squirting gas.
With Canuck gas, good luck and props if you can get them running good with crap 87. Then if the crap 87 sits...all I hear is 'Nelson' . The handbook says 91, but 87 is 'acceptable'. If I'm not driving the car alot, I use only 94. If I am driving a lot, I can cheap out a bit w/ 91. I dunno, I have no problems keeping 5 M's and a F running.

[SgtRauksauff]

Thanks for the tips, guys!

I actually pulled the air cleaner cover, and the choke was wide open as could be, I shut it, and it yanked itself back open, so the thermal spring in there seems to be working, and the flap isn't sticking.  Obviously, I'm going to need to properly adjust the carb. linkage and such, to make it act "properly".

The more I thought about it, I'm pretty sure that it's a dirty fuel tank. Seems it ran fine when turning, and fairly good acceleration right after turning, which I think washed the pickup clean.  But then, after driving gently in a straight line, the pickup gets clogged until there's no more draw on it (engine off) or it gets washed away (turning/sloshing.)

I got my o-ring and locking ring from Rock Auto in the mail yesterday after all this happened, so tonight I might just drop the tank, and see what's inside.  First, I'll just use my electric pump to suck it as dry as I can get it, then hopefully if there's crap inside, I'll be able to blow it out with compressed air.

I didn't even think of the tank not venting at all, but just pulling the cap off should remedy that possibility.

I'll be getting some new tires tonight, el-cheapo $55 215/70-15 all-seasons from Discount Tire. I waffled for a bit on getting something better, but right now I just want the car to be safe to drive without crappy old separating dry-rotting firestones.

--sarge

[Diplomatic Immunity]

Just a thought before you drop the tank. How old is the gas in the tank?

A month or so back I didn't have enough gas in the tank to make it into town to fill up, and the only gas I had around was crap gas that was in the parts car tank that I put in my car to replace my holey tank that gas had to be 4 to 5 years old. and while driving to the station my car behaved much like the way you describe you car running.

Gas nowadays doesn't seem to even store for 6 months before it goes bad.

[Bill55az]

High mileage cars with v8 often have cold weather driveabilitly issues due to the exhaust crossover of the intake manifold being plugged with carbon.

[Ice Cold]

Does it get cold in AZ?

[Bill55az]

Some winter nights it gets a bit below 40....
I used to live in SE Idaho, tho, where I had the unhappy experience of cleaning out the crossover of an intake manifold...

[SgtRauksauff]

That's an interesting point about the crossover, I'll keep that in mind. However, it's been 40's for the lows lately, 70's in the highs, so I wouldn't expect this to be a cold-weather issue.

The fuel is probably about 1.5 gallons of old crap gas that I drained out of another car before, and then about 10 gallons of brand-new 87octane (10% ethanol, it's VERY hard to find non-ethanol gas  anymore).  And one can of seafoam.

I think maybe the fuel sloshing around in the tank may have pulled/lifted any scale off the walls, and it's just floating about waiting to be sucked out.

I put the car on ramps last night, and PB-Blasted the snot out of the two bolts for holding the tank straps.  If they're still tight, i could always just use a torch to heat them up, right? lol.

If it comes to the worst, a new tank is only 81.79 bucks at RockAuto, for the Spectra tank, with lock ring kit and a 3-yr. warrantee.  Cool part is, one of their main hubs is only an hour away from me, so I tend to get things pretty quickly from them.

I planned on dropping the tank originally, but then I got greedy and cut a corner so i could get the car up and driving and show it off to some friends.  One step forward, two steps backward.  I have GOT to make myself remember, "stick to the plan!!!"

--sarge

[Ice Cold]

I'm still against 87   I have never have issues with 5M's and neither does the local M crowd here. 87 is crap in a lawnmower. I pulled a 79 Lebaron out of a garage that hadn't been started in 8-10 yrs. A battery/some 94  and I've been driving it for a yr. I even have cars sit and have no problems, as long I have a battery and 94. I'm pretty sure US gas is even worse than Canuck.

[Diplomatic Immunity]

Well If you put Seafoam in it then yeah you undoubtedly have a bunch of rust crap floating around in the tank getting sucked onto the pickup plugging it up in no time flat.

[SgtRauksauff]

Well, I drained, then dropped the tank.

It is CLEAN inside there.  took a high-powered LED flashlight and a mirror, and looked around all inside.  no dirtiness on the inside, it looks like fresh new metal.

The sock/strainer, however, does look dark brown.  Do they make replacements for them?  If so, where?  I couldn't find a listing at Autozone, napa, rockauto, or the local place.

--sarge

[Diplomatic Immunity]

I don't know if they sell replacement pick up screens or not but if the tank was clear no sediment in the bottom or nothing then your problem has to be elsewhere, if your still worried about the pick up screen you can probably just run with out it since you have a filter before the pump.

 Was the tank empty when you got it or did it have some gas besides what you added. A gauge on E still has a significant amount of gas in the tank so if that was bad and you put in 1.5 more gal of bad gas and a can of seafoam then filled it with 87 octane the gas may still be the problem. 87 is nowhere near good enough to make bad gas usable adding cleaning solvents isn't going to help either. I would advise that since you more then likely pumped out the gas from your tank before dropping it you use the stuff for mower gas/weed killer and fill up on mid grade 91 or better. I don't know how its done in WI but here next door to you Cheeseheads in MN we only put the corn juice in the cheap gas, super is ethanol free.

[Ice Cold]

Our gas is 'up to 10%' ethanol for a good 10 yrs or so. I know of a lot of Mopars and other street cars from the 70's that just sit because they can't run on 94.

[SgtRauksauff]

Most of our gas has ethanol in all three grades, occasionally I see a place without.  We basically have 87, 89, and 91or 93, and no 94.  I did drain the tank, but there's still a bit in there, maybe a gallon or so, but i think I'll dump it and go new.  I'm used to using 93 on all my other cars, but that's because they're either turboed (ford escort and Volvo) or tuned a bit (toyota corolla).  I guess I'll shop around until I find a place with no ethanol in the mid or high grade, and see what happens.

An interesting puzzle:  when I was pumping the fuel out of the tank, via an electric pump, I opened up the gas cap to listen for bubbling letting me know the tank was as empty as I could get it.  HISS goes air into the tank, with vacuum.  I wasn't sure, so I tried it again, and sure enough, the tank was under a pretty good vacuum, just from the pump sucking out gas. Does this indicate a failed gas cap, that may be causing this?  Or maybe a clogged charcoal canister?  Does the engine need to be running to create low pressure for the canister to work?

I feel kinda silly not checking the cas cap in the first place.  With an oh-so-tasty lip-lock, I was able to suck air through it, but not blow air through it. so theoretically, there should NOT have been vacuum in the tank, yet there was.  I made sure to close the cap with 3-4 clicks when closing it, so it should've been venting properly.

On a good note, there was a bit of rusty flakes on the trunk floor, so dropping the tank gives me a chance to clean the area and re-seal it against terminal cancer.

Thanks for the input, guys!

--sarge

[Patrick]

Yes a venting issue can stall the engine. At one time my old fifth ave actually sucked in the gas a little. It went THUD! when I opened the tank.