Fuel filler keeps backing up... Ideas?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Stroked

Full Access Member
Joined
Dec 26, 2011
Posts
2,248
Reaction score
97
Location
Beloit, Kansas
First Name
Jared
Truck Year
1984
Truck Model
K10
Engine Size
305
Ok looks like I've got something to take a look at then. If that dont work I might bust out my jack nascar style and lift the one side while I pump lol!

Or take a couple wood blocks to drive up on :gr_grin:
 

da_raabi

Trailer Park Supervisor
Joined
Aug 7, 2013
Posts
1,403
Reaction score
901
Location
FloriDUH
First Name
Adam
Truck Year
1986
Truck Model
c30
Engine Size
454
So none of the above helped the situation at all... SO. Heres my thought. I'm going to disconnect the filler vent (the smaller line next to the large filler) and replace it with a long line of heater hose out to the back bumper with an air cleaner on it. The reason for this is I looked in the filler, and the way it is designed makes it so that when fuel backs up, it fills both lines thereby making it impossible for fuel to enter the tank. This is why I am thinking run a SEPARATE vent line out to the back, thereby eliminating the (what I think) problem. More to come...
 

GTME94

Full Access Member
Joined
Jan 20, 2013
Posts
441
Reaction score
32
Location
Metro Detroit/Holland, MI
First Name
Terry
Truck Year
86
Truck Model
C2500 C6P Camper Special
Engine Size
454/TH400/14bff 3.73
Just be careful about your new line getting full and leaking fuel out. I think the design is intended to go back into the fill pipe so any splash back or burps of fuel goes back into the tank and not out somewhere. I looked at the service manual and pictures of my tanks without the bed on. The two lines go into to two different openings in the tank, I don't think they should both get full of fuel unless something is wrong.
 

da_raabi

Trailer Park Supervisor
Joined
Aug 7, 2013
Posts
1,403
Reaction score
901
Location
FloriDUH
First Name
Adam
Truck Year
1986
Truck Model
c30
Engine Size
454
The problem is not the tank side, I think it is the filler side. Fuel had backed up, and from what I could see it had completely blocked the opening for the vent in the filler neck. Obviously I am having a venting issue, because I could not find any kind of clog, and at this point I cannot put any more than 10 cents of fuel in at a time and by the time I hit a gallon it backs up completely where I can no longer put ANY fuel in.
 

da_raabi

Trailer Park Supervisor
Joined
Aug 7, 2013
Posts
1,403
Reaction score
901
Location
FloriDUH
First Name
Adam
Truck Year
1986
Truck Model
c30
Engine Size
454
Well I tried a few more things...

1. I disconnected the vent line at the charcoal canister to eliminate the possibility that it might be plugged... NO GO

2. I blew out the main vent line with air, got some junk out. I then blew out the two vent lines from each tank (the T into the main line going to the front right next to the tank switching valve). Funny thing is that when I blew out the line going into my malfunctioning tank (the only one in service right now), it blew a ton of fuel out the filler, which I thought strange. Anyway STILL NO GO

So at this point I think I need to drop the tank. My thought is this: in this picture you can see the three outlets (supply, return, and vent). Below one of those lines is what looks to be a valve of some kind (hanging into the tank). For those who have torn one of these apart before is that a pressure release valve? Could it be that that is blocked up and unable to open? I am thinking that this may be my problem, because I can think of nothing else it could be!

You must be registered for see images
 

Forum statistics

Threads
44,414
Posts
957,061
Members
36,748
Latest member
mrevil
Top