Need to drop fuel tank.

[MRS]

I have a 89 GMC motorhome cannot get more than 20 gallons in the tank I did clean and check vent hose was clear. Plus was going to pull hose off of tank but tank is full so I figure must have a bad pickup tube or broken one was wondering how to get the top off the tank with out braking anything looks like I just tap the ring off right? There are three hoses coming off the top so figure one to fuel pump and one to generator is the third one a vent hose. Thanks for any help 20 gallons with a 454 dose not get you very far we call it gas station hopping....

 

[Harritwo]

Take the three hoses off. One will be supply, one return, and the sending unit wire. The third line may or may not be the generator. Take a NON SPARKING ROD, (I use brass round stock) and tap the ring on each tab. When the ring turns, it will unlock and the entire assembly picks up out of the tank. You may have to twist/turn to get it completely out but it is fairly straight forward. On the fuel systems that have an electric fuel pump in the tank, there is a rubber hose about 3 inches long between the pump and the tube that has split causing you not to be able to get all the fuel out that is classified as usable. When you reinstall the sending unit, ensure that the o-ring is seated properly and not stretched/deformed so you can get a good seal. Hope this helps.

 

[MRS]

Thank you yes it helps a lot looks like I have to bend one tab down then knock the ring loose. I do have brass round stock I will be using also, will be using it this weekend dry camping in the desert and carrying extra gas with us will give it a go next week Thanks again....

 

[no704]

Hose 1) high pressure from pump
Hose 2) return from regulator
Hose 3) vent to filler neck

Before dropping tank with engine running pull the fuel pump fuse and run till it stalls. This wil deplete pressure in the high side line so you have less chance of getting sprayed in the face with fuel.

Are you able to fill the tank but can only use half? Or does it only fill half way and the pump clicks off? If the latter check that the filler hose is all down hill. If there is a low spot it may close check valves and not allow a full fill.

Clean the tank before opening. Sounds like ya might have a stuck roll over valve.

Good luck,

Neil

 

[no704]

Forgot to add: if you don't want to wrastle a full tank just get a length of fuel hose and attach to pump line out of tank or @ filter wherever is easy. Put other end in jerry can or other car and jump fuel pump relay w key on. Let er pump. Just keep an eye on flow as to not let pump run dry.

Neil

 

[MRS]

no704, Thank you was wondering how to relief pressure for the hose. I can fill tank full but will only use 20 gallons and that is it I did some checking an sounds like there is a assist pump in the tank also so not going out this weekend so I will drop it Saturday and see what I got. Also my vent to filler neck comes off the tank right beside the filler neck so will trace that line and see where it go's Thank you will update when I find out what is not working..... P.S. figure the bottom of tank must be full of crud and some old gas.

 

[no704]

The vent hose that comes off the filler tube will go to the tank. Sometimes there will be an in line roll over valve, some are built into the sender in the tank. Either way if that valve is stuck ya will not be able to fill the tank. Sometimes it just takes some well applied hammer taps to unstick the valve.

 

[no704]

Ya most likely will want to get a new sendin unit. These are usually made so they can be used in a number of different tanks. So the pick up tube is spring loaded to rest on the bottom of the tank, connected to the pump with a corragated tube. That tube is most likely cracked sucking air when not submerged. Concidering the age I would replace the whole unit pump and all while u are in there. Check out your local Napa, stray from discount chain stores for this part.

 

[MRS]

Thanks have a Napa right down the street here I did get 15 gallons out tonight will clean the tank off in the a.m. and get the rest of the fuel out tomorrow. The connection on top of tank with the wires does it just pop off or twist off?

 

[MRS]

Ok can pull the top off with out dropping tank lots of room under there here is what I found the hose here in the red was gone. Motor would pop a little when first starting but not now and with only 20 gallons in it would not run I drained all gas and added 20 gallons and runs great.

 

[MRS]

no704 NAPA did have the new o-ring and lock ring in stock 6 bucks what a deal thanks for the help...

 

[Gyrene]

Good for you for getting it fixed.

 

[MRS]

Gyrene, Thanks was really worried it was gona be bad but worked out great thanks again. Plus throwing it out there incase some one else had a similar problem.

 

[no704]

Glad u were able to get fixed up!