Inaccurate Fuel Guage

[edfer]

Our 2002 reads between 3/4 and full after we have spilled gas on filling (so we know its full). Before we add 14 gallons (about half a tank) the gauge is reading about 1/4 or less. When the guage is reading empty we still have about 7 or 8 gallons. Is there an adjustment somewhere? Is this normal for the CC or do we have a bad sending unit or gauge?

[todda]

RE: Inaccurate Fuel Guage

edfer-
i don't know of any inboard boat that has an "accurate" fuel guage. between my previous ski brendella, and now my 1999 SN 196, i consider mine to be very accurate, and it is off about 1/4 tank most of the time by my calculations. i know of a person who has gone in and replaced the tank float, and that didn't solve his problem whatso ever on his malibu. good luck!

todd

[kentsmith12]

RE: Inaccurate Fuel Guage

I have a 2000 Pro Air and I think my tank is 34gal. I have the same problem. After filling my tank runs down fairly quickly to a 1/4 tank then hangs out there for a long time. I usually fill up when it gets in the middle of E to 1/4 quarter and put in 19gal. So I guess at some point I'm going to let it go all the way down to E just to see how many gal. it actually holds. I hope the kiddos and wife aren't with me... My former boat was a MC Sammy Duval - loved that boat and it's fuel gauge (for a boat) was very accurate. I love my CC but the fuel guage just takes getting used to - I try not to look at it any more and know that I've got a 14 gal reserve...

[boysrus]

RE: Inaccurate Fuel Guage

The shape of the tank has a lot to do with it. Mine (01 Air) has a wide flat base, then steps down fairly small about 1/2 way up. Results in blowing through the 1st half (according to the gauge) pretty quickly, then much slower below 1/2 tank. Since the senders I'm familiar with are linear reading, they don't read accurately with a tapered tank. You can do some adjustments to float rod length and angle to try and trick it, but it's probably not worth the hassle.

[AirJeff]

RE: Inaccurate Fuel Guage

Just an fyi there are no tricks we can do to our float in an '02. It is a fully enclosed magentic style.

[Rick]

RE: Inaccurate Fuel Guage

I have had about a dozen boats in my life and not one of them has had an accurate guage. That is because the way the tanks are built and the fact that a boat doesn't stay level or have any baffles in the tanks to prevent sloshing. If you really need accuracy you can get a flow meter guage that is usually used on larger boats and measures fuel used. You reset it each fill up and then watch how much gas you have burned. These guages run from inexpensive (paddlewheel) to expensive (sonar) flow detection. Personally after several tanks of gas i can figure out how much gas I have based on the guage change from idle to plane.

[Chad52]

RE: Inaccurate Fuel Guage

I've been having some sporadic issues with my fuel gauges also on my 03 SANTE. Everytime I go out on the water I top off the fuel tank so I know that it's full. On at least two occasions, after only a couple of hours of riding, both my analog and digital gauges will report low/no fuel, and then after a few minutes will recover to normal readings. Since both gauges are off, I'm thinking my sending unit may be going out. Anybody else every had this happen? Where can I get a new sending unit?

Chad

[Canuked]

RE: Inaccurate Fuel Guage

I know this is a bit off topic but I got my first inboard (an 01 air) last year and I can't belive how good on gas it is compared to my 115hp outboard. I swear it uses less fuel and we usually have about 1000lbs of ballast.

I agree the first 1/2 of the tank goes down very quickly but it only represents 1/4 to 1/3 of the total fuel thats actually in there

[mf01]

RE: Inaccurate Fuel Guage

My gauge is highly inaccurate. I looked at it before I went to the gas station and it had just above 1/2 (I think it's a 26 gallon). I put in 5 gallons and it was coming out of the tank.

I agree on the consumption. I use to have a Twin Cyclinder 110hp 14.5ft Seadoo Jetboat. I think I use the same or less with my 5.8L 310 HP engine with a loaded boat. I thought I would use a little more gas with the V8.

[M3Fan]

RE: Inaccurate Fuel Guage

If I fuel my boat too quickly or with too much gasoline flow, it will get caught up in an air pocket or something and behave exactly as if it were full, spitting the gas right back out. If I back off on the flow, it will take it in with no problem. Just something to keep in mind- the tank may not actually be full if it comes back out at you. I have to be very careful to fuel mine slowly.

[mf01]

Re: RE: Inaccurate Fuel Guage

If I fuel my boat too quickly or with too much gasoline flow, it will get caught up in an air pocket or something and behave exactly as if it were full, spitting the gas right back out. If I back off on the flow, it will take it in with no problem. Just something to keep in mind- the tank may not actually be full if it comes back out at you. I have to be very careful to fuel mine slowly.

Yep I figured that out the first time I filled it up. Some of the auto click mechanisms on gas pumps flow too fast. Sometimes I have to do it by hand or put something smaller under the clicker.

[coloradonautique]

Chad,
New sender can be purchased direct from WEMA (the OEM supplier). I got new stainless ballast and gas senders this year.

www.wemausa.com

The ballast gauges were WUF12s (12" plastic, no longer available)
I think my gas gauge was a stainless 14".

I replaced everything with the SSL models of the oem lengths.


All,
Yup. The shape of the tanks really confuse the poor linear senders/gauges. My '01 AN tank is an L shape and the gauge cranks through the first 1/2 tank then sticks at 1/4-1/2 forever. I bet someone could come up with a neat add-on circuit to compensate for the tank shape since the sender just puts out a linear resistance slope but it just is not worth the time. Learn your boat and spend your time on the water. Yellow_Flash_Colorz:

Cheers,

Lorin