The Stovebolt Site Forums The Shop Area Engine Shop How Much Gas Does it Take??

Trying to get this thing timed and doing a vacuum test, ran my tank dry. I added a gallon,(last night),with enough left over for a half dozen primes,to get it running again. To make a long story short,I added another gallon,(tonight),and still no gas to the carb. none to the pump,either! I pulled the sending unit,and the screen is still dry,with two gallons in the tank! I'm going to add another couple of gallons tomorrow after work,and see if I can get fuel to the carb,and check for vacuum leaks.Hopefully get it timed ,too. AARGH!!

The pickup isn't bent or something?? John

Nope,New 2 years ago,from L.M.C. I was careful installing it,and checked the length of the pick-up tube,on inspection. Looked like the screen should reach the bottom of the tank! Screen is clean as a whistle,B.T.W.!

Is the supply line from the sender to the fuel pump plugged?

How large a tank does a 2 ton use?? John

What year and type of cab?

1955-2nd series standard cab: 17.5 gallons

I'd think a couple gallons it should start picking up gas???
John

Tim it may be listed as 17.5, but it takes 16 gallons to fill it when you run it dry. Ask me how I know... Lol!

my 58 runs out with 6 liters left, "empty" level depends on how well the pickup is positioned, and of course how level the cab is sitting

Bill

If parked in a slight incline...the Gas may all be on one end, below where the Pick-Up Screen-end can pull it in.


I usually put in four Gallons, when starting with an 'empty' Tank.

Jus' cause I have been through the "Heck I have TWO Gallons in there now, and still no Gas coming through!" routine myself...Lol.

I'm on vacation this week,so I'll be trying to get these problems (timing/vacuum/carburetor),figured out!! If the tank's listed at 17.5 gallons,and it takes 16 to fill it,that tells me that there's still at least a gallon and a half,(or so),still in the tank! I'm done using ethanol,if that's the case! The tank's 2 years old,and i don't need added moisture causing rust scale,like the one I took out!! It's a wonder the truck even ran,with the looks of the old pick-up screen!! Thanks for all the input!! If I can't get it fixed this week,you may see it posted in the "Swap Meet" section! This thing is draining my finances to the point of an eviction notice!! At least I had the FUN of driving it about 1,000 miles,in the last couple years!

How does doing a compression test run the gas tank dry?

If it ran before it should run again......Don't give up hope Willy. Who needs money anyway. A 2 ton might make a great RV.....

John

My question as well. I've never in my life done a compression test on a running engine.

Perhaps the OP is attempting to warm the engine up to operating temperature before doing the compression test.

It's not a compression test,but a vacuum/timing test,and yes,it needs to get up to operating temp. Haven't been able to get it to run without the choke full-closed,(even when warmed-up)! Ran out at least 10 gallons in the last 2 weeks trying to set the timing. Today,I got it started,and sounded like a Detroit in the middle of the winter!I guess what truck mechanics call "chasing". Idle would speed-up,slow down,(almost to 75 R.P.M.)then speed up again.while I was looking for a screwdriver,to adjust the air/fuel mix,the engine started gaining R.P.M.,(like a runaway),but thanks to the vacuum leak,ran out of fuel before redlining a cold engine. Engine ran tops of two minutes. Two gallons added,before adding two more gallons today. No gas getting to the pump!! Back-blew the lone from the pump,to the tank,and all I hear is straight air,no gurgling! Maybe a dumb question,but would a faulty fuel line cause a poor vacuum reading,if a line was sucking air?? No,this is not a fuel/vacuum pump.No,I've never heard of doing a compression test on s running engine,either,since you have to relieve the tension on the valve springs,first. Then you have to LISTEN for air to escape from affected valve,which would be impossible on a running engine. Heck,I can't find a vacuum leak,even after doing a torch test!! I.R.B.4.I.F.I. "(It Ran Before I Fixed It)"

Ok... That makes more sense then. If it only runs with the choke closed, it's not getting fuel through the low speed jet. It has gotten plugged up or something. You should start with the basics and follow a procedure and not jump around from one thing to another.
First.... Do a compression test. Pull all the plugs and remove the coil wire. Block the throttle wide open. Check each cylinder and write down the reading starting with #1 cylinder (front one). Each time crank it the same number of revolutions. You can hear it each time the cylinder you are checking comes up on compression stroke. This can be done on a cold engine. After you get a reading on all cylinders go back and do it again. This time add two squirts of oil from one of those old time oil cans into the cylinder just before checking it. Write these readings down noting they are with oil.
Then post the results.

I'll go through he trouble of doing a compression test,but shouldn't need to. the head was rebuilt,2 years,and about 600 miles ago. I had hardened seats installed. When I had it apart,there was no cylinder ridge,in any of the 6. Engine does not smoke,even at start-up. I REALLY think I have a vacuum leak,just haven't found it yet. The "BB" in the accelerator pump discharge is lodged,(Rochester B),and won't come out. Is that the location of the "low speed jet"?I know I installed the right one,when the carb was first completely rebuilt,2-years ago. Just might be time to replace it?? Thanks!

A vacuum leak. Could it be the diaphragm in the advance on the distributor? I would unhook and plug any other vacuum sources to things such as 2 speed rear end, Hydrovac ect..... se if that makes a difference. Sounds like the engine proper is okay.....

John

Thanks, Whitelightning!! Brand new H.E.i.,but seems like the V.A. mechanism is tight. Hard to move manually. It moves,with about 5# exertion. I have the vacuum gauge connected to that source now,but maybe should move it to a different location? Duh! Now I remember that Mike B,(I think) told me to connect it to a vacuum source,like the wipers,or 2-speed adapter. carb base may not give a good reading at idle,especially with the choke closed. Next time,I'll take notes,since the truck is 10 miles from my computer! you guys give great advice,if only I'd heed to it!! I.R.B.4.I.F.I.

Didn't realize you had an HEI on your engine, but then I didn't know about an alternative vacuum source needed for them. I guess we both learned something..... :-)

John

Just because everything was good 2 years ago doesn't mean anything. Valves stick and so do rings from sitting.
Any vacuum source that originates below the throttle plate is the correct vacuum for the vacuum advance.
The check ball doesn't have anything to do with the low speed circuit. However, depending on which position it is stuck could cause different issues. If it's stuck in the closed position you won't get a squirt when you open the throttle . If it's stuck open you will probably get an overly rich condition since the plunger will force fuel backwards.
A cool tool to find vacuum leaks is was of those cheap party fog machines. I bought one last winter and attached a hose to it to connect to the intake on my BMW. I had smoke coming out in several places I was convinced weren't leaking. Car runs like a dream now.

Cool idea! I work at Goodwill,and we get those things donated all the time! THANKS!! That's exactly what my situation is! the spark plugs are two years old,but they were all soot covered. Rich fuel condition. New plugs last week. No paperwork on H.E.I.,as far as point gap. .050?

I would close the gap to .035 and start there