LUVTruck.com

been starting this truck and driving every now and then,went to drive it the other day and started for about 15 sec,then died and hasnt started back,decided to check to see if it s getting gas and it wasnt,put a lil gas in the carb fired right up and died,my sending unit i thinks bad cause the gas hand hasnt worked since i bought it,so i put gas in it,and still want start,removed line from fuel filter under hood no gas coming out while cranking,any suggestion please,thks

_________________
they never learn,cause they only watch us work!

Could be:
-fuel pump (frame-mounted electric or engine-mounted mechanical? don't know on an '81). If electric pump (a)check the fuse and/or fuel pump relay (b)run a jumper from the battery, if noisy or a weak flow replace it. The fuel filter should be before the pump- they get full of dirt & fail. Mechanical pumps rarely fail without leaking, check for vacuum at the supply side while cranking.
-clogged fuel pick-up screen, blow air through the lines into the tank.
-hole in a fuel line causing the pump to suck air.

_________________
'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.

i notice while i tryed to crank it,i heard the sound coming from it and then faded away after a few sec when i stopped trying to start it,and i found a what i think is the fuel pump on the right side bed rail,so do i just run a jumper wire from the hot to the battery and just leave it grounged where its at ,and is the fuel filter on the left side on the rail (drivers side)i read something about them being 2 fuel pumps another 1 in the tank,but not sure,also i was going to change the the sending unit because my fuel gauge isnt working,i noticed on the side of the tank (passenger side) that there was that round place that looks just like the in of the new sending unit,are those pretty straight foward to put on?and by the way thanks for your help so far too,greatly needed

_________________
they never learn,cause they only watch us work!

Separate the outlet side fuel line at the electric fuel pump, attach a wire to the positive battery post, touch the other end to the pump terminal(do this under the truck). The pump should start running, it should pump a strong continuous stream, vibrate just slightly and NOT thump or whine. Change the fuel filter in front of the pump first & blow through the line towards the tank. If the pump seems good reconnect the line to the carb, then sparate the line under the hood, momentarily jumper the pump again to see if you have fuel to the carb. If so see if it pumps while cranking with the line separated. If not it's a fuse or the fuel pump relay- the pump is wired through a relay to run only when the engine is turning over, you bypassed the relay(and the fuse that goes to the relay) with the jumper.
A rusty tank will cause an electric pump to fail, they will start making noise that you can hear while running & the volume will reduce over time. Any aftermarket generic electric pump with a 3-7 psi range can be used, it will just attach differently than the stock pump.
You only have the one pump, only EFI engines have an in-tank pump & they're a high pressure unit, not the low pressure like in your truck.
The sending unit is mounted in the top of the tank, there should be a spade connector with a wire attached, wriggle the wire to make sure the connection is good or the guage won't work.

_________________
'78 Chevy LUV,1.9,4sp,headers,31's,SAS Dana 30,Dana 20,SOA rear w/Aussie Locker, rough body, bought new 12/4/78.
'87 Trooper,2.3,5sp,headers,31's,ball joint flip & spacer,Aussie Locker rear,Superwinch hubs,brush guard w/5.5K winch,more to come.