Suzuki fuel gauge dead

[localboy]

Need some advice on what I should check for. It was working last season; now nothing. Does not move at all. I cleaned and checked the sending unit in the fuel tank. No change. Nothing looks different. The entire Suzuki gauge pack seems wired in parallel and the other gauges (engine tilt & volts) are functioning.

[South of Heaven]

[thataway]

Consider that the fuel tank sender is an arm attached to a rheostat. There is about 200 ohms resistance across this. Testing is as below:

From Jamestown Marine:

Fuel Systems (Marine)
Voltage - "I" to "G" terminal - 10 to 16 volts.
Test gauge as follows: Connect "hot" wire to the "I" terminal and ground wire to "G" terminal. Remove sender (usually pink) wire from back of gauge. Gauge should read below "EMPTY". Next, add a short wire from the gauge's "S" (sender) terminal to ground. Gauge should read above "FULL." If the pointer sweeps back and forth, gauge is OK.
The sender can be tested by checking its resistance with a volt/ohm test meter (use analog meter) as follows:
Remove sender (usually pink) wire from sender.
Connect two test meter wires to two sender terminals (or center terminal & flange if sender has only one terminal).
Move float arm by hand. Approximate values: Empty = 240 ohms, 1/2 = 103 ohms, Full = 33 ohms. (Teleflex sender: rheostat housing installed upside down will cause gauge to read backwards. See illustration.)
Sender resistance tolerances at full may cause the gauge to read 2-3 pointer widths either side of the full mark.
The sender will accurately operate only one standard gauge at a time. It is not designed for dual station use with standard gauges.
Gauge will not operate accurately from more than one sender at a time. Some installations use a switch to connect one gauge to various tanks, one at a time.
Sender will not operate in water tanks. Rheostat will become electrically "open".
Be certain sender dimensions are adjusted per the instruction sheet.
If sender is "open" (infinite resistance) gauge will read below empty. If sender is shorted (0 resistance) gauge will read above "FULL".
Some "bowing" of the flange may occur when the 5 mounting screws are tightened. The gasket under the flange will normally seal the flange properly, but do not overtighten the mounting screws.
Sender must be grounded, or gauge will always read "EMPTY."
If sender is installed in a tank not designed for a sender, care must be taken to seal screw threads. Sealant under screw head is also advisable. Sealant must withstand gas and diesel fuels.

[BrentB]

Bob

Thanks for posting!

[Aurelia]

Good luck on the testing Mark. If your was as accurate as ours on the 25, you might not miss it much. After trying to use ours for some guidance, we ended up just setting a GPS based trip meter and that worked out well. You could always replace it with a sticker.

https://www.amazon.com/Gauge-Level-Funny-Helmet-Stickers/dp/B00OSAL480

Greg

[localboy]

I'm going to ground out the sender today and see if the gauge changes at all. I did some reading last night on it. Very similar instructions to what Dr Bob posted. If the sender tests OK, I'll use his instructions to test the gauge.

Greg, you are correct. The thing is not accurate and it bounced around, but it does give you some idea of what you have left. If I can't get it to work, I'm gonna fill the boat and go off the Garmin unit since we have a fuel use sensor now (GFS10 I believe). The full tank will give me a better starting point than I currently have.

The tach is working fine as is the "hour meter" when you first hit the key to power the system. It's a 2006 Suzuki DF150 with appropriate gauge cluster. Even has a useless "speedometer".

[localboy]

After doing a simple test (grounded the pink wire) I determined the sender was bad. I pulled it and confirmed it was via an ohm resistance test. Tested OK "full" but as I "emptied" it, the meter showed no reading. Purchased a new WEMA brand from Fisheries Supply and the gauge is back working.

All electrical should be as easy to understand to a novice like me. It did educate me on resistance, ohm measurement, how to use a multi-meter to figure it all out though.

The tank is just under 10" (~9 7/8") deep so I purchased a 9" WEMA unit, in case anyone else with a 25 encounters this. The original sender was an arm/float type, like an old toilet tank. The new WEMA one is a float that moves up and down on the shaft. More reliable, or so the inter-web says....

https://www.fisheriessupply.com/wema-usa-sss-ssl-flanged-fuel-water-tank-sensor

[AstoriaDave]

local boy,

Good on ya for this: All electrical should be as easy to understand to a novice like me. It did educate me on resistance, ohm measurement, how to use a multi-meter to figure it all out though.

Does my old teacher heart good to see this. A volt-ohm meter is a really versatile tool.

Agree the stock tank swing arm sensors suck.

[localboy]

Dave, I have no problem admitting I don't know everything (contrary to what my wife might say ). Electrical (both car & boat) has always been my Achilles heel, along with dual carb synch/adjustment. I ask dumb questions, read what I can and fumble fark my way thru when possible. The more I learn, the more confident I become. When we stop learning we best just lay down and die...slowly.

Aloha, Mark

[cmetzenberg]

[thataway]

First I would swap the gauges, or really just put the Starboard wiring to the port gauge after pulpit the port tank wiring off. This will let you know if it is the gauge.

As the usual suspect is Corrosion, I would also go and clean up all of the terminals. Probably the last place is going to be the most difficult--and that is the actual sender. But at least clean up those connections (including the ground).

[cmetzenberg]

[thataway]

Should be pretty short jumpers since the gauges are close together on the console as I recollect. I usually carry 4 short alligator clip jumpers in my electrical bag, and then several long lengths of wire--thus able to make jumpers even the length of the boat if necessary..

Good on cleaning the terminals!

[cmetzenberg]

[thataway]

There are fuel units which may be better than the EOM: You have to know the depth of the tank of course. Most all have the same resistance value.

Example is SSS/SSL Sender – SAE 5 Hole Pattern Mount American Standard 240-33 ohms (240 ohms at empty, 33 ohms at full)