1984 K30 fuel issues, dual tanks

[46binder]

I just bought a 1984 K30, and have a couple issues.  Gauges have been acting funky, they work, then don't work, oil pressure now doesn't work and choke light stays on, fuel tank was empty at 1/2 a tank on the gauge, list goes on.  Problem I have now is it won't start.  It was only 8 degrees here in Wi. the other day, and I have no gas from the fuel pump now.  Theres gas in the tank, it was a new fuel pump that was working, but the day before I saw the needle on the gauge switch as it was idling in park.   Was it possible it switched tanks on me?  When it was warmer, I heard the noise of the valve switch, now, nothing.  I want to only use the passenger side tank, since the drivers side leaks, so that one is empty.  Can I just disconnect the hoses on the valve and use a double male barb fitting, bypassing the drivers tank?  Do I need to do anything with the switch wiring?  Right now I don't know whats bad, the switch, or the valve, but would just like to disable both.  Thanks for the help.

[rich weyand]

If you don't hear the click anymore, the solenoid died.  When it did that, it reverted to the tank that is selected when the coil is not energized, which sounds like its your LHS tank.  You can swap the tank hoses and sender wires at the solenoid to make the RHS tank the default and you should be good.  You can also hook the RHS tank line directly to the line up to the engine bay with a double-barb fitting as you suggest.  Make sure you wire the sender wire past the broken solenoid as well, to get proper fuel indication.  If there are return lines (six hoses on the valve) then you need to connect the return line from the RHS tank to the one going up to the engine bay as well.

[Boone83K10]

I just bought a 1984 K30, and have a couple issues.  Gauges have been acting funky, they work, then don't work, oil pressure now doesn't work and choke light stays on, fuel tank was empty at 1/2 a tank on the gauge, list goes on.  Problem I have now is it won't start.  It was only 8 degrees here in Wi. the other day, and I have no gas from the fuel pump now.  Theres gas in the tank, it was a new fuel pump that was working, but the day before I saw the needle on the gauge switch as it was idling in park.   Was it possible it switched tanks on me?  When it was warmer, I heard the noise of the valve switch, now, nothing.  I want to only use the passenger side tank, since the drivers side leaks, so that one is empty.  Can I just disconnect the hoses on the valve and use a double male barb fitting, bypassing the drivers tank?  Do I need to do anything with the switch wiring?  Right now I don't know whats bad, the switch, or the valve, but would just like to disable both.  Thanks for the help.

Why disable it. The switch is cheap and so is the selector valve. Most likely the valve switched which resulted in no gas. They default to the primary tank (driver on 84) when they fail mechanically. You need a six port selector valve. Take off two bolts and one electrical connector, along with fuel lines and it's off and back on. The gauge was funky because the selector valve failed electrically as well. It controls the signal from the fuel sender inside the tanks.

The choke light stays on when it isn't receiving a signal from the oil switch. The oil switch had probably failed which is why the gauge is dead and the choke light is on. Check wiring at oil switch, replace if necessary.

 

[rich weyand]

$60.  http://www.amazon.com/ACDelco-467513-Fuel-Selector-Valve/dp/B0016HT92G/

[bd]

I just bought a 1984 K30, and have a couple issues.  Gauges have been acting funky, they work, then don't work, oil pressure now doesn't work and choke light stays on, fuel tank was empty at 1/2 a tank on the gauge, list goes on.  Problem I have now is it won't start.  It was only 8 degrees here in Wi. the other day, and I have no gas from the fuel pump now.  Theres gas in the tank, it was a new fuel pump that was working, but the day before I saw the needle on the gauge switch as it was idling in park.   Was it possible it switched tanks on me?  When it was warmer, I heard the noise of the valve switch, now, nothing....

No joke - do the turn signals work?  Probe the Ignition, Gauges and Choke fuses with a test light.

Boone and Rich, I believe the '84 used a ratcheting, 5-wire valve that could have been 3-port or 6-port, depending on whether there was a 1/4" return line from the fuel pump.

[46binder]

Thanks for the replys, I guess I should also say its not totally a 1984, Vin says it was a 2wd long bed with a 305, but the frame its sitting on is a 1 ton dana 60 front, goodwrench 350 , t400 and np205.  Front frame horns were trimmed to fit the newer body.  Dont know the age of the frame.  I think there were 6 ports on the sender.   It has just been so cold here, no ambition to work on it.  Doesn't help that its parked outside,  not in the garage.

[rich weyand]

If it's the five-wire setup, then I would think it would be the motorized Pollak valve.  Three wires are for the tank senders and the gauge, and the other two are for the motor: reversing them selects the other tank.  The issue here is the motorized valve is silent, and the OP said the valve stopped making the characteristic noise, so it sounds like the solenoid valve to me.  Or is there a five-wire solenoid valve?

[46binder]

I crawled thru the snow this morning, pulled the valve, there's 5 wires and it says Pollak.  Will be pricing one out for replacement.  Turn signals do work, high beams don't, but I could see PO changed switch by cutting all wires and using cheap wire connectors.  He also must not have known about the little button under the switch to remove the knob.  I think I will be chasing wiring gremlins for awhile.

[bd]

Snow!  "BRRrrrrrrrrrrrrr!!!" 

Verify that ignition power and ground are reaching the selector switch before replacing components unnecessarily.  Cobbled wiring can be a real headache!  Factory wiring and service manuals are available for download to your hard drive from our Technical Pages if you need them.

[rich weyand]

Sounds like the motorized Pollak valve.  If so, the two wires for the motor should reverse polarity with the switch on the dash.  That is, the two motor wires will read +12 in one direction with the switch in one position, and +12 in the other direction with the switch in the other position.  The sender wires should be pink, pink with white, and pink with black; the motor wires are the other two.

[Captkaos]

You can pick up a Pollak valve from any auto store.  NAPA, Autozone, Advanced Auto, etc...

[46binder]

Picked up new valve, truck started up.  Fuel gauge didn't move when I tried to switch tanks.  Didn't play with it though, called it a night.  I am concerned about the size of the fuel line hose.  Valve directions said use 3/8 and 5/16" line, and that's the size rubber I got.  All three  supply line ends on the truck had little to no resistance slipping inside the rubber hose.  The hose was tight on the valve side.  Didn't take a caliper to it, but could it be 1/4"?  I don't think it was replaced before, and it had the flared ends.  I know it is supposed to be 5/16" supply.  Hope the clamps hold it tight enough so I don't get leaks.

[Captkaos]

Supply is 3/8", return is 5/16".
you need clamps on the rubber hose...

[46binder]

I put clamps on when I installed it, but the lines sure seemed small, wound up taking a caliper to them, they had an OD of 1/4"
Don't know why or how.  Line from mech. pump to carb is 5/16"  Oh well, its running. 

[bd]

The factory return line on carb'd engines was 1/4", bleeding through a ~0.060" orifice built into the pump.  TBI used a 5/16" open return from the regulator.  Factory fuel supply lines were 3/8" for both.