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Jimmy update and fuel problem

Joel Wilson

Joel Wilson

1/2 ton status
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Jun 7, 2017
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Location
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Long story short, I moved from Cali to Kentucky last Sept. Original plan was to have the Jimmy and small trailer loaded with everything that the moving company couldn't move. Dogs, guns, ammo, cannon, all my reloading equipment and some other big stuff. Hottest week of the year, I head east on hwy 36, get about 1500 ft above sea level and the Jimmy is chugging hard. It's a long steepish grade and it's 115 outside. Pull to the side of the road, check both fuel filters and they are clear. Still no fuel. Let it cool off and I make it and I make it about 3/4 of the way home before the same thing happens. No fuel. Before my brother gets there with a tow strap, I have no less than 5 people give my decent offers to buy it. Get home, replace the fuel pump head out next day, same spot, same temps, same temps. Towed home. Replace fuel pump with Holley and put it low and up front under radiator. Head out next day, starts WAY easier in the morning, get about 2 miles further up the mountain, same problem. Towed home. By now, the Jimmy is beginning a sordid love affair with the tow truck.

Both engine temp gauges were normal. Engine oil temp was normal. Trans temp was warm but not hot. I was running supreme unleaded fuel and had full tanks each time. Jimmy was squatting a little, maybe an inch to the rear. Thank you overload springs. Jimmy was definitely loaded. Fuel lines were wrapped with heat shield. I did not notice any of the rubber fuel hose being sucked in. Fuel gauge reads normalish

Causes and options once I get the Jimmy transported to Kentucky. Vapor canister? Something restricting the line? Pick up tube gummed up? I really liked the cold start of the electric fuel pump. If I replace the tank and put in electric, do I need an inertia switch? What's my best option for converting to electric? Anything else I may have missed.

Thanks and I will give an update in the lounge on everything else that happened.
 
You have a fuel return line? I'm sure you've gone through this before, but hot fuel problems should be relatively easy to address.

I'd strongly consider EFI if you are already to the point of electric pumps, like the easy startup, and are having issues.
 
I am wondering if there is a problem with a line right at the top of the tank.

With the electric pump being so far away from the tank, it could suck suck air at higher flow rates, (like under load) especially if there is a small leak to allow air in.

Or, can you verify that the line coming off of the sender is good?

I wouldn't think that the pick-up tube is gummed up, but possibly the sock is clogged.
 
Joel sorry Jimmy is adding to your moving stress.
You remember my fuel delivery issues. I had good clear lines and new pick up, old one was perfect for changed any way.
Only adding a 3/8 inlet outlet Holley pump mounted to front of my fuel tank skid plate, bottom of pump almost even with bottom of tank. Solved my fuel issues.
I had it 2" higher on a 6%+ grade it failed. Had to move it down to get going again.
I never did find out why I had fuel delivery issues. My current theory is my overdrive rpm was to low for mechanical pump, or my cam pump lobe is warn.

Hope you enjoy Kentucky, and are well
 
Return line installed?
If not plumb in one of these up near the carb wix 33041. Use the 5/16 vent line from the tank to the canister as a return. Cap the canister to carb line if it’s there. You will have to use a 1/4 fuel line. Leave the gas cap loose to vent and go for a ride.
Will fix your vapor problem if that’s what it is until you find a permanent solution. Can’t be any fuel leaks though.

8D805ABF-10AA-4EC7-A6AB-97DCAE6F490A.jpeg
 
blazer74 said:
Return line installed?
If not plumb in one of these up near the carb wix 33041. Use the 5/16 vent line from the tank to the canister as a return. Cap the canister to carb line if it’s there. You will have to use a 1/4 fuel line. Leave the gas cap loose to vent and go for a ride.
Will fix your vapor problem if that’s what it is until you find a permanent solution. Can’t be any fuel leaks though.

View attachment 444828
Click to expand...
I had a return line on the mechanical fuel pump. There shouldn't be any leaks. I had a local mechanic replace all the flex lines going into and out of the fuel tank last time I had it smogged
 
Wes Harden said:
Joel sorry Jimmy is adding to your moving stress.
You remember my fuel delivery issues. I had good clear lines and new pick up, old one was perfect for changed any way.
Only adding a 3/8 inlet outlet Holley pump mounted to front of my fuel tank skid plate, bottom of pump almost even with bottom of tank. Solved my fuel issues.
I had it 2" higher on a 6%+ grade it failed. Had to move it down to get going again.
I never did find out why I had fuel delivery issues. My current theory is my overdrive rpm was to low for mechanical pump, or my cam pump lobe is warn.

Hope you enjoy Kentucky, and are well
Click to expand...
How did you attach to the hardliners along the frame rail?
 
3/8 fuel line, with 3/8 nipple threaded into Holley pump.
With appreciate hose clamps
 
Joel Wilson said:
I had a return line on the mechanical fuel pump. There shouldn't be any leaks. I had a local mechanic replace all the flex lines going into and out of the fuel tank last time I had it smogged
Click to expand...
I’ll add that I tried the return line on the pump and still had the issue. Return up near the carb was the only solution for me. I also tried the high volume EDL mechanical pump.
Never had the problem for years then all of a sudden, there it was.
 
If your a carbed engine, the problem is highly int the metering jets.. I've seen this before when a friend from Texas came and visited me when I lived in Idaho. We were going this switchback to get to the top of the mountain and his vehicle stopped, basically chocking, we when in reverse rolled the road and the vehicle started back up and was driving good until we reached the same place in the road. So, the jets were set up for 0 sea level but at 10,000 feet above sea level, they didn't enough air to operate right
 
I am going to give you my opinion.

Is the hard line from the pump to the carb between the water pump and the timing cover? If so move it. What you are describing is exactly what I went through on Fugly. Was boiling the gas in that tube.

I am back on the mechanical pump after 2 electric pump fails.
 
ktmoutfront said:
I am going to give you my opinion.

Is the hard line from the pump to the carb between the water pump and the timing cover? If so move it. What you are describing is exactly what I went through on Fugly. Was boiling the gas in that tube.

I am back on the mechanical pump after 2 electric pump fails.
Click to expand...
I replaced the hardline awhile ago with fuel injection hose and it is not close to the block
 
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