Moving Down the List..

[ironart]

Thanks again for all of your help with my other problems..!!
The last thing on my list is the fuel gage.

When I bought the coach the old owner told me that the fuel gage had not worked for some time....He just filled it up every 400 miles weather it need it or not..?? I guess I could do that too but I really want that gage to work....

Does anyone have any suggestions as to where to start..??? I really don't want to drop that tank (75gal) if I don't have to.....Although it really is not that hard to do....plenty of room and only 4 bolts...

The symptoms are, that the gage goes to "Over Full" whenever I turn on the ignition.....then seems to relax and go back to about 3/4 Full when the power is removed.... Could sure use some advice here....

Thanks

Paul

 

[ironart]

Re: Moving Down the List..

Oh....I guess I should have told you that this Dolphin sits on a 1991 Ford F53 chassis....

 

[Kirk]

Re: Moving Down the List..

There would seem to be two possible causes, the tank float assembly or the gauge. Wire harness could do that, but probably isn't. Since it does move some, that makes me tend to suspect the in tank part, but you would have to drop the tank to check that. If you have some way to send a varying voltage to the gauge you could test it. The catch is to know what the voltage range should be. The local library probably has a shop manual, such as Chilton's that would tell you, as well as giving some trouble shooting hints.

 

[ironart]

Re: Moving Down the List..

Thanks Kirk,
Since I am getting an over filled reading on the fuel gage with the ignition ON and it does move back to 3/4 full when the power is removed...It made me think it was the tank sensor or a short in the wires. Is that the right thinking or am I thinking backwards..???? Someone told me that It was an Open Ground..??

I am going to FORD tomorrow and see if I can order a wiring schematic (with wire colors identified) for this chassis Hopefully , with that, I will know which color wires I am looking for...?? I hope it will be detailed enough to tell me which wires are in which bundle....

 

[ironart]

Re: Moving Down the List..

Shucks....If You think it's in the tank sensor and I do have to drop the tank....I guess I should head over to Rod's He did offer me a Job.....But when he realizes that I can't fix my own fuel gage problem, He might have second thoughts.... :laugh: :laugh: :laugh:

 

[Darwin]

RE: Moving Down the List..

Find the wire going to the float in the tank, disconnect the wire, your gauge should go to empty. Ground the wire the gauge should show full. If this is true then the gauge is OK, then If your wire is good then I would suspect the float assemble in the tank. I droped the tank on a chevrolet (60 gal) by using a floor jack with a piece of plywood between the jack and tank. I would suggest you have some help. Get as much fuel out as possiblle. Chevrolet has an electrict fuel pump in the tank, if ford does I would suggest replacing while the tank is off. I hope this helps.

 

[Guest]

Re: Moving Down the List..

Paul ,, i bet u have a have a float prob ,, i fixed an Airrex wih the same probs as ur's ,, the tank on that one didn't need to be dropped ,,, it was a 36 fter with tag axles ,, anyway the sender unit came out thru the top of the tank ,, with no prbs ,, had to remove the tags axle wheel though ,, but i found the float ,, which looks like a little barrel ,, and made of brass ,, had a hole in it where the thing was soldered together ,, anway i ordered a generic sending unit form napa ,, and robbed the float ,, which was plastic ,, same size and all ,, now MH is happy ,, hope this puts some insight into u'rs ,, :approve: :approve: :laugh:

 

[ironart]

Re: Moving Down the List..

Wow....Everyone seems to be pointing to the fuel sender....I am going under there tomorrow and will try to locate the wire and do the test....I have not looked under the bed yet.....I might get lucky and have a little cover plate that will expose the sender for removal.......Wouldn't that be nice... :laugh: :laugh: :laugh: :laugh:

 

[ironart]

Re: Moving Down the List..

I went to Ford today to try to get an idea of what I was up against. There is a fuel pump in the tank and it is an integral part of the fuel sender ie. One Unit...!!!
Ford quoted $350.00 for the part..

They did have the little "barrel" float that Rod was talking about but when I told them that the gage goes to Over Full with the ignition on they said No that was not the problem.

I guess I am just going to have to get it out and look at it. It might be that the float is just stuck in the "UP" position and a little cleaning might just do it.

 

[ironart]

Re: Moving Down the List..

Well, the bed trick didn't work...I forgot about all the storage and pass-throughs under the coach so the floor under the bed is no where near the top of the fuel tank.
Back to the under coach removal method....I did a lot of thinking about this and I am going to use two come-alongs. Will anchor one end to the frame on one side and sling the cable under the tank and anchor the cable end to the other side of the frame. Lowering one at a time (very slowly) I should be able to get it down without too much trouble.......I have used a floor jack in the past (I have done this before) but this coach is too high off the ground and my floor jack is just too small....and I don't want to buy another one and besides that.....One jack will only give me one point of support.....Not good with a tank this large..(75 gal)

Any Comments on this method or should I just take it to the shop and pay the price..????

At my age, you begin to understand your limitations. :clown: :clown: :dead: :dead: :disapprove:

 

[C Nash]

Re: Moving Down the List..

Paul, before dropping the tank ck the wiring harness. I was thinking (dangerous for me)that an open wire would cause the needle to go past full with key on and most guages,dash,are just the free floating kind so the needle will just kind of float with key off. Is there a connector near the tank that you can disconnect. If you know some of the techs at ford they might have a old sender that you coud use just to ck before dropping the tank. Sounds as though your method of droping will work or you could apply voltage to the tank pump and pump all the fuel out. A word of caution If you are using a droplight keep it away from anywhere near the tank. A spill on the bulb will creat quit a show. Believe me been there done that or the kids at school did.

 

[ironart]

Re: Moving Down the List..

Hi Chelse,
You are the second person that mentioned that it could be an open wire....I wonder..???

According to the Ford Tech I talked to...... it is a shorted situation. He explained that the resistance in the gage circuit was reduced as the float rose to the top of the tank, and the test for the gage was to remove the wire from the sender and the gage should go to empty....short the wire to ground and the gage should read over-full..(which is the current symptom) Now that is the way it is in General Motors vehicles but Ford may be another story. They are noted for doing things backwards....I remember in the "Old Days" Ford use to use a Positive Grounded system on their cars when everyone else was Negative Ground....Ok, I guess that Dates me...
Further investigation is called for.....The Rig is parked on gravel at the moment and it is hard for me to get under there comfortably with the rocks......I am moving it today to a nice spot on my concrete driveway where I can get under there and take a good look........Will report back..

Paul