Fuel Tank Selector Switch

[Ron Sebastian]

New problem all of a sudden. How many things wrong could make the engine not idle right and make the transmission wind out to higher RPM shift point, all happens when I switch fuel tanks. When I switch back to the other tank everything acts right again. Could a bad ground cause this? Bad selector valve? Where do I start? When I first crank the engine, I hear a familiar sound from the fuel pump on one side. When I try to crank the engine on the other fuel side, the pump sound is different.

 

[bucket]

Sure sounds like a dying fuel pump.

 

[Ron Sebastian]

Bucket, you are probably right. All weekend the problem came and went. I'll start with the easy fuel filter swap and see how that goes. Not looking forward to dropping the tank

 

[Ron Sebastian]

I never noticed a different sound from each pump on startup, have to start paying more attention.

 

[Grit dog]

Can't disagree with dying fuel pump. And those symptoms are possible, with shifts hanging if it's just not making power, you're further into the skinny pedal than you would be normally and trans thinks you're trying to go fast and no shifty 'til later.
As nice as your truck looks, I'll presume the bed bolts aren't rusted? I'd seriously consider removing the bed before dropping the tank, and especially if both are old/original fuel pumps and there's a chance you'll replace both of them.

 

[bucket]

I agree, if it's a long bed with the longer 20 gal tanks, I'd pull the bed and change out both pumps. If it's a shortbed, the tank senders are under the cab kinda, so you still have to drop the tank. However, having the bed off does make it easier to access the fuel lines at the sender.

 

[SquareRoot]

I replaced the passenger side 20 gallon tank on my 85 this weekend. Pulling the bed was not an option. Done it in the driveway with a creeper and transmission jack. Took me two days to replace everything (tank, sender, hoses, new no-squeaky strips and new wiring for the EFI pumps).

In summary, I'd rather get an enema from Edward Scissorhands and Captain Hook before doing that again!

This rates right up there with changing steering columns and converting from auto to manual transmissions. It might be awhile before I get the desire to do the drivers side. Best of luck.

 

[Grit dog]

@SquareRoot , yeah if pulling the bed isn't an option, IMO it's a miserable process. Not necessarily quicker to remove the bed, just easier.

 

[Ron Sebastian]

Miracles do happen. As I was going to show a buddy my problem, I started on the other tank and it started fine like always. I switched tanks and she just kept on humming. He said doesn't sound like there is anything wrong to me. The problem apparently fixed itself, thank god. I did not want to go through the tank dropping and not sure I could anyway. Thanks for all the input folks, it did help.

 

[SquareRoot]

Fixed itself until the next time when your miles away from civilization. I hate those self fixes.

 

[AuroraGirl]

imagine how the dutz/clutz/Newbie I was when I replaced mine LOL 20 gallon tank coming down wasnt so bad but figuring out the damn bracket thing and stuff and spending way too much time to delicately remove sender unit just to have the whole lock ring retainer thing snap and make that a waste of time lol

then eating rust. lots of rust flakes.

 

[Ron Sebastian]

I don't mind waiting for the inevitable. Still have the other side, I hope.