Tank selector valves

[rsmarr1982]

Are tank selector valves known to go bad? I seem to have a fuel flow problem. I installed a new pump and checked all of my lines but sometimes at random my truck will start to Surge. I have a clear fuel filter installed and I've noticed that the fuel just seems to trickle inside the fuel filter. My truck has auxiliary fuel tanks on each side I was wondering if the fuel tank selector valve is known to go bad and maybe I could be sucking air

[B. W.]

The only issue I've ever had is they start to leak fuel. I have one now that weeps when changing tanks then stops. I would think that trash (rust) int the tanks or a bad fuel pump before the selector valve. what's the fuel in your filter look like? Does it flow better on the main tank?

[rsmarr1982]

I only use main tank and it's been cleaned along with line. Auxiliary tanks I've never used. Fuel in filter is clean as can be. New pump is an ac delco

[B. W.]

Gotcha, you can by-pass pretty easy. Might be worth a try.

[jocko]

The worst that usually happens is that they freeze in a position and you can't select the other tank or they leak - but I doubt it is related to a surge. Sounds more like a carb issue to me. If it runs normal and the filter looks the same as when it surges, I doubt there is an issue with the fuel getting to the carb. Might be worth looking at the carb. I'd also check for leaking vac lines to the distributor. When does the surging occur? Under accel load? Idle? Part throttle cruise, etc?

[rsmarr1982]

Carb has been rebuilt. Fuel doesn't fill the clear filter like it should barley trickles in sometimes and then sometimes is fine.

[57taskforce]

Is your tank venting?

[haysonj]

I had a 65 dump truck with the three way valve and it sat a year or two. Varnish built up in the lines and when I started driving it again some of the varnish broke loose and partially blocked the valve. Truck would run fine until I hit a hill and would not get enough fuel. If you still have the old lines from the tanks to the valve I would take them loose and make sure they are clean

[rsmarr1982]

Originally Posted by 57taskforce

Is your tank venting?

It's a new cap. I get a tiny bit of gas odor when I stand near cap so I believe so .