Replacing the OEM fuel gauge?

[Ericb760]

Today I did my 30 minute monthly exercise of my generator. It ran fine under AC load. I had put $50 worth of gas in the tank six weeks ago but my gas gauge is on empty now. I know I have at least 1/4 tank because the gennie ran fine. So, it seems I need to replace the gauge. Has anyone done this before (I'm looking at you, Rick!)?

[Rickf1985]

The  gauges themselves very rarely ever go bad. The sending units do go bad more often and the wiring to the sending units and the grounds from the sending units especially go bad. I have not done mine. I have done probably a hundred on various vehicles over the years and they vary from ten minute easy to ten day hard. Yours is going to be on the bad end of that scale unfortunately. You have two options, drop the tank or cut a hole in the floor. Personally I would drop the tank for the main reason that you have 40 plus year old hoses and lines up there that all need attention. With the tank down you can do it all at that time. Getting the tank out is not an easy job since the fill hose and fill vent are wedged between the frame and the body and then they go through the rear cabinet. You cannot get to the clamp to get the hoses off right at the tank so the first section of hose has to come out with the tank. This is something I can explain how I did it on mine but it is best done on the phone since it is rather involved and I simply cannot type it all out here.

[Oz]

Do you have the manual for it?  If not,
Go to the member area and check.  Not sure if that will cover it, but worth a try.

[Ericb760]

I was really hoping you were going to give me some better news. Oh, well. If that's the case, I just don't have the space to drop the tank right now. Question: An I okay running if I know I have gas in the tank? I mean, the sending unit is just that, it doesn't have anything to do with actually sending fuel as that would be the fuel pump. The gauge does work. After I put $50 in it moved up to about 1/4. Am I safe with filling the 60 gallon tank and just assuming I'm getting less than 10 MPG? (I always keep a 5 gallon can onboard just to be safe).

[Oz]

Definitely always assume you're getting less than 10mpg!  10 is very, very rare unless you tavel all highway on flat land.
Be safe, assume you're getting 7mpg.

[Rickf1985]

I will say you should be safe BUT, like I said before the lines are 31 years old so no guarantees. Also remember that 5 gallons spread over that huge 60 gallon tank bottom will be about 1/2" deep, not enough for the pickup to reliably suck up. 5 gallons at 6-7 MPG equals 30 miles. Welcome to Class A world!

[LJ-TJ]

   Once again Rick and Mark are spot on. LJ and I had the same problem with our 75 before I finally changed out the gauge and sending unit. Have you got two tanks or a reserve in your tank? We kept a log on how much fuel we took on board at fill up. We drove figuring on 5 miles to the gallon and kept track. Eventually we figure out how far we could make it on a take of gas. Luckily we have two tanks so we would run the main tank out,switch to the reserve and stop at the first gas station in route and refill. I did eventually switch out to two Autometer fuel gauges and sending unite and am very satisfied with them.

[Ericb760]

I will say you should be safe BUT, like I said before the lines are 31 years old so no guarantees. Also remember that 5 gallons spread over that huge 60 gallon tank bottom will be about 1/2" deep, not enough for the pickup to reliably suck up. 5 gallons at 6-7 MPG equals 30 miles. Welcome to Class A world!

So, this happened today. My wife expressed an interest in learning to drive the RV. I "thought" that it needed gas per my original post so we drove to the gas station. When I looked at the gas gauge it said "full". I could have sworn it was nearly empty the last time I ran the gennie which was just ten days ago and had Rick's sage advice in the back of my head. My wife said, "Maybe you filled it up the last time you filled the propane tank..." I didn't think so, even though I did just fill the propane tank last week, and proceeded to fill the tank but it kept shutting off like it was full. I put in around two gallons and figured my wife was right, I must have filled the tank already even though I knew I had a problem but the topping off lulled me in to a sense of security. So, we go to some isolated county roads and she drives around for awhile and we return home. I figured I'd run the gennie for a bit to exercise it again and turn on the AC and fiddle around for awhile. After about ten minutes it sputters and stops. Restart and it sputters and stops again. Fuel gauge says "full" still. I had a few gallons onboard so I throw about a gallon in the tank. Gennie starts right up and runs for about twenty minutes and dies. On a guess I run down and fill a ten gallon can and proceed to dump it in. It takes every last drop, so there is no way my fuel gauge is reading right. I KNEW that I had not filled the tank, but I trusted that gauge even when I knew it was wrong in the back of my head. I'm just glad that we were close to home when it happened, and running the gennie (which shuts off when the tank is one quarter full) alerted me to the problem. Moral: Always trust your instincts, especially when you are getting conflicting information from your rig. Looks like I'll be dropping the tank to replace the sending unit like Rick says. I'll wait until summer is over to do that...

[Oz]

That's almost funny... almost.  These old rigs have a way of playing their games, don't they?

[Ericb760]

That's almost funny... almost.  These old rigs have a way of playing their games, don't they?

In hindsight, I just didn't want to address this problem properly. The gas pump continually shutting off had me questioning my belief that the tank was nearly empty, which should have never been the case, when the reality is that getting a good seal on the fill neck has always been a problem, and I KNEW THIS! Oh well, live and learn...

[Rickf1985]

Remember those 30 year old lines I was talking about? I will bet the gas fill vent hose has collapsed and that is why it keeps shutting off on you.

[Ericb760]

Remember those 30 year old lines I was talking about? I will bet the gas fill vent hose has collapsed and that is why it keeps shutting off on you.

When it rains, it pours, right? Any advice on how to un-collapse the vent hose?

[Rickf1985]

Replace it. Not trying to be smart but once they get hard and get a bend in them they collapse, I have gotten by by putting a hose clamp around the collapsed spot and tightened it just a hair to make the hose round again and open it up. This will only work if you have clear access to the spot in question. Since you have the same rig as me I know you don't have that option. It has been a while since I have been in mine but if I remember correctly I had to cut a fair size section out of the back corner of the top of the compartment right where that hose set goes through. It is behind a shield screwed to the side and top of the compartment and I had to cut out that section to access the fuel pressure regulator, which by the way is ALSO wedged directly behind the cabinet brace!!!!! Winnebago builders are freakin' idiots!!!!!!!!!!
Rant over............. So if I remember correctly the section I cut out may have made it a little easier to get mine apart just in that I could see a fraction more than with the compartment complete. I have pictures of all of that somewhere.

[fasteddie313]

It took me like an hour or 2 to lower the tank on my rambler enough to replace all the fuel lines and then strap it bak up..
Just lowered it like 8-10 inches.. didnââ,¬â,,¢t snag in the fill lines that I can recall..

Turned out a lot easier than I expected.. The fuel lines were like completely shot..