Mercury Optimax Gauges... reliable ?

[Scotty]

I bought "mikes" valiant dr 600 and am very happy with it. It has smart gauges fitted to the console and I'm curious as to the reliability of the fuel gauge. Mike had filled the boat with fuel before he delivered it to me, and every time I take it out it shows 56 gallons. Is the optimax very miserly on petrol or have I an issue here with the gauge or sender in the tank ? I'm getting worried.

[Turbodiesel]

It depends, the Optimax gauges will only read from a Wemer ( i think thats how you spell it!!) Fuel tank sender. Otherwise you need to run a seperate fuel gauge. Also you need to check a few things. If you have a Wemer sender then you need to make sure the gauge has been calibrated correctly. When In CAL 2 on your gauge you need to tell the gauge when the tank is empty, Half fuel and Full. Its a pain in the arse to set up!!. Check in your owners manual to see how to get to the gauges Calibration. Also you must check that the gauge is set to display the fuel tank level, this is also in CAL 2 you can either switch the tank display on or off. If its switched on and is not able to talk to the fuel tank sender it will display it as a fault because the wont be able to get any info from the sender. Sounds complicated but its quite easy really!!!

[Dirk Diggler]

Originally Posted by Turbodiesel

the Optimax gauges will only read from a Wemer Fuel tank sender.

I don't think that's quite true, I've seen all different makes of senders being used!

[Turbodiesel]

Originally Posted by Dirk Diggler

I don't think that's quite true, I've seen all different makes of senders being used!

Well maybe, but im just going on what i was told at work the other day when i fitted a 135 opti to a Delta Rib. Will find out when i get into work on Monday for sure.

[Scotty]

Oh feck ! Now here's another reason the zodiac was so good... You could see the level of fuel in the tank. The tank in the valiant is under the floor. Mike.. Mike are you out there ? Was the fuel gauge accurate ??

[Paul F]

Cant say about being accurate, but can say that it was working and was callibrated by me using the take it to a petrol station and slowly fill up method.Sender is correct and wired correct. Have you accidently gone into callibration mode and inputed the wrong info?
Paul

[Scotty]

Originally Posted by Paul F

Cant say about being accurate, but can say that it was working and was callibrated by me using the take it to a petrol station and slowly fill up method.Sender is correct and wired correct. Have you accidently gone into callibration mode and inputed the wrong info?
Paul

Paul,
Thankfully I never touched anything. It just seems to be very economical. Mike had left a lot of fuel in the boat and the gauge says 56 gallons still. Maybe I need to go for a very long journey to check economy /gauge. I was going to open the fuel gauge inspection cover but brought the wrong screw drivers with me.... maybe just as well. Paul F my mobile no is +353-86-2552012 if you text me I will call you back to discuss this. Thanks for all your help.

Luke.

[Cookee]

Wema US spec senders were recomended by Barrus to me - There is no reason why other makes shouldn't work if they have they same resistance and wiring.

[Daniel]

As a rule of thumb that engine on that boat will burn about 30li's an hour and a litre a mile upto 3/4 throttle / speed, almost regardless of any other factors.

Why are you using the "float" gauge - it'll never be very accurate on any boat with any tank. The opti "fuel used" gauge is very very accurate - if it was reset when the tank was full you can have good confidence in the amount left.

[Scotty]

Originally Posted by Daniel

As a rule of thumb that engine on that boat will burn about 30li's an hour and a litre a mile upto 3/4 throttle / speed, almost regardless of any other factors.

Why are you using the "float" gauge - it'll never be very accurate on any boat with any tank. The opti "fuel used" gauge is very very accurate - if it was reset when the tank was full you can have good confidence in the amount left.

I think its time to fill the tank and read the manual