Fuel Issues 1984 Alaskan CJ8

StoneyWelborn

Alaskan Postal Junkie
LIFETIME
CJ-8.com Member
City
Puyallup
State
WA
#1
Rig was running fine then all of a sudden stopped getting fuel. I replaced the fuel filter and pump, blew out the line back to the tank with no luck. Decided to pull the tank and found the sending unit was toast. I installed a new sending unit, new fuel vents and rubber lines, then blew out the lines again before reinstalling the tank. I added 5 gallons of fuel to the tank and tried starting it with no luck. I hooked up an auxiliary tank to the pump to make sure it was working and it is. I've narrowed down that the fuel is not making it from the tank to the pump. Not sure where to go from here without removing the tank again. Any advice or help is appreciated.
 

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spankrjs

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Biloxi
State
MS
#2
I had this issue on one of my Scramblers with a 20 gallon tank:

Make sure the rubber supply line that goes out of the sending unit does not get kinked when reinstalling the fuel tank.

I had this happen on a Scrambler with a TBI 350, and the electric fuel pump would not overcome the kink.

Not saying this is your issue, but worth a shot :thumbsup:

Post #304:

https://www.cj-8.com/threads/spankrjs-1984-long-term-project.32726/page-16

1590682806802.png
 

AJ2393

Scrambled in the Head
LIFETIME
CJ-8.com Member
City
Westport
State
MA
#4
Sounds like there must be a fuel line pinch or blockage somewhere between the tank and pump. I am assuming the metal fuel lines are somewhat new when you did your restoration. If there is no pinch in the line, based on the looks of that old rusted sending unit, I wonder if there is rust in or floating in the gas. That "possibly" could block the pickup screen on the sending unit although it would need a lot of junk in the gas to do that on a new unit and a plastic tank. How did the fuel look in the tank? Clean? Dirty? Just throwing out ideas.

Also, I assume your running a factory 258 engine, factory carburetor setup with mechanical fuel pump (no inline pressure regulator).
 

jammer1

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Maple Hts.
State
Oh
#5
If it's not a kinked hose and you blew air through the hose (if blocked the air should have backed up where you put the air to) check to make sure the fuel line isn't broke or rotted. The pump would pull the air through the break and wouldn't have the suction to pull the fuel from the tank. I would hate to think a new pump is bad (not creating enough suction to pull the fuel from the tank but enough to pull fuel from the tank next to the pump.
 

Mancunian

Lifetime Member
LIFETIME
City
Bridgeport
State
WV
#6
Do you have a spare electric pump you could hook up to see if that pulls any fuel - is there enough in the tank?
Or just attach a tube to the pump outlet and crank the engine to see if the mechanical pump works.

Otherwise i agree with Jammer1 - it's either blocked line or a line with a hole that's pulling air.
 

ag4ever

Average Nut
LIFETIME
CJ-8.com Member
City
Richmond
State
TX
#7
Don’t have anything to add, other than I could take that mess off your hands for you. ;)

I hope you have a better time at it than I did. Mine was a bad case of slime in the tank that resulted in a complete tear down.
 

bigwalton

Picture cravin' AK Postal nut
Staff member
SOA Member
City
Dexter
State
MI
#8
Wondered about hooking a tank right to the pump temporarily too. If you did that, I’m betting cracked line.
 

mwqpd11

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Coopersburg
State
PA
#9
My fuel pump stopped working. Thought the pump was bad and replaced it. New one didn’t work. I blew a fuse and had no power to the pump
 

StoneyWelborn

Alaskan Postal Junkie
LIFETIME
CJ-8.com Member
City
Puyallup
State
WA
#10
I had this issue on one of my Scramblers with a 20 gallon tank:

Make sure the rubber supply line that goes out of the sending unit does not get kinked when reinstalling the fuel tank.

I had this happen on a Scrambler with a TBI 350, and the electric fuel pump would not overcome the kink.

Not saying this is your issue, but worth a shot :thumbsup:

Post #304:

https://www.cj-8.com/threads/spankrjs-1984-long-term-project.32726/page-16

View attachment 83834
Checked it last night and it was not pinched. I’m going to look at the line this afternoon.
 

StoneyWelborn

Alaskan Postal Junkie
LIFETIME
CJ-8.com Member
City
Puyallup
State
WA
#11
Do you have a spare electric pump you could hook up to see if that pulls any fuel - is there enough in the tank?
Or just attach a tube to the pump outlet and crank the engine to see if the mechanical pump works.

Otherwise i agree with Jammer1 - it's either blocked line or a line with a hole that's pulling air.
I ran an auxiliary tank to the pump and it worked fine. I know the issue has to be the fuel line from the tank to the pump. I really don’t want to pull the tank again.....
 

jammer1

Scrambler Junkie
LIFETIME
CJ-8.com Member
City
Maple Hts.
State
Oh
#13
If you can disconnect the rubber fuel line at the steal line (by the tank) hook a 3ft fuel line into a fuel can of fuel. Line good pump will have fuel.
 

HighSierra CJ

Scrambler Enthusiast
LIFETIME
CJ-8.com Member
City
Ducor
State
Ca
#14
I had a fuel line come apart on the inside one time. Kind of a flap that created a reverse check valve situation. That may have been what happened on your old fuel line.
 

StoneyWelborn

Alaskan Postal Junkie
LIFETIME
CJ-8.com Member
City
Puyallup
State
WA
#15
Thanks for the insight! Found the issue. There is a rubber line that goes around the shock between the steel line from the tank and the steel line to the fuel pump. When I grabbed it, it felt super soft and think it may have collapsed when the pump created pressure. Replaced it and fuel started flowing!!!!!
 
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