Bad gas, carb float or ?

[don t. - 72gmc]

1970 GMC Sierra, 2500, 396/400/402 cid, th400 w/factory air that needs a recharge.

About 18 mths ago, filled tank and added Seafoam a bit strong for winter storage.
Ma got sick, and for all intents truck did not run in 2012. It never left the barn.
Month ago I got er running.
2 weeks ago, rebuilt q-jet carb.
1 week ago I fixed gas leaks
This past Sunday morning she was running good.
Sunday afternoon wife and I wanted Ice Cream. Climbed in and she ran like ship from the moment she fired. No choke, pump pedal to get on road, would die almost immediately. Would restart, the same way, w/o a problem.
Just 10 minutes ago she again runs good, albeit a bit sluggish, after a 5 mile trip. Never got that far Sunday afternoon.

I've got 1/2 a tank of this Oct 2011 gas and Seafoam.
If it is bad gas, what is the easiest way to drain?

Maybe the float is getting hung up? I know it was seated correctly before I buttoned it up.

Kinda confused with the good truck/bad truck.

Thanks...don t. ....

[WIDESIDE72]

Does your carb appear to be flooding? I am more convinced that you have a fuel problem. Im not familiar with what seafoam promises to do. Does the gas in tour area contain ethanol? If so you need to reat gas with something to keep the fuel drom absorbing moisture as ethan is "hygroscopic" much like brake fluid.

I am no expert but have run into problems similar to yours. I see that joe gibbs racing is making an ethanol treatment specifically for vehicles driven infrequently. Here it is in a case of six:

http://www.drivenracingoil.com/dro/c...tive-case.html

Jegs has single quantities on ebay:
http://item.mobileweb.ebay.com/viewi...d=111127308196

I ordered a couple today to try.
Posted via Mobile Device

[don t. - 72gmc]

"Does your carb appear to be flooding?"....
It seems more like starvation. I can keep it running by pumping the pedal, but will not (did not) hold an idle. Acceleration was very weak and sputtery. When it dies, I need to pump the pedal 2 times to get er running again.

I use Seafoam. Some use Sta-bil. Usually have no problems with over winter storage, but not this long.

Yep....we've had 10% ethanol in my area for many many years.

Im thinking its not carb related.....
....cuz it does run, kinda decent at times.
....I've had the carb open a few times since the rebuild, thinking maybe a piece of crud is in a jet. I did not see anything pop out, filter in carb is fine
....not float related cuz it does run semi-decent. I do recall hearing it banging around putting it back together.

Thanks....don t. ....

[cdowns]

i'd suspect your fuel strainer on the sending unit in the tank is clogged with crap// i'd use a hose and siphon out what gas u can from the tank then remove and inspect your sending unit

[don t. - 72gmc]

Originally Posted by cdowns

i'd suspect your fuel strainer on the sending unit in the tank is clogged with crap// i'd use a hose and siphon out what gas u can from the tank then remove and inspect your sending unit

Easy enough, but a question.
Truck still has the cardboard around the tank.
Honestly...aint looked, but any idea how is the cardboard is held in place? Don't want to ruin it if at all possible.

Thanks....don t. ....

[FLDBRED]

I got a nice tip on this forum just a short time ago. To check for bad gas, simply diconnect the fuel line at the fuel pump.Take a fuel line and place one end in a gas can with clean gas, the other end gets connected to the fuel pump. If you had bad gas after a few minutes the clean gas will get to your carb. I did this, and found out indeed my gas was bad. I had been trying everything prior to this!

[don t. - 72gmc]

Originally Posted by don t. - 72gmc

I've got 1/2 a tank of this Oct 2011 gas and Seafoam.
If it is bad gas, what is the easiest way to drain?

I figured I start with the easy stuff.
Went to tractor Supply, got one of them cheap siphon tubes.
I drained about 14 gallons of gas, which I used in my new-er pick up w/no problems.
Poured in about 10 gallons of brand new gas.
So far...so good...but I aint gone very far from home.
Idles nice, acceleration is good and smooth.

One last thing is to fix a small leak where the gas line mates to the carb.

Thanks much for your help....don t. ....