Hi Guys,
My Fuel gauges on my 41 PC have never worked very well since I've owned the boat. Indicated full might be full and indicated 1/4 might be empty and empty might be empty etc.. Basically I've been keeping track on cruises by run time Almost screwed up two years ago and ran pretty low on the port side because I forgot to account for generator run time.
The gauges want to "see" 33 to 240 ohms range from full to empty. The senders have high and low limit potentiometer adjustment and I screwed around with them and I couldn't get them into range. The stock senders measure the capacitance of the fuel by running a small current from one isolated plate to another and turning it into a resistance electronically. Very accurate but a little complicated. I'm allergic to complicated.
I purchased two float style senders from WEMA I think about $60 each. The tank is 30" deep and the stock sensors are 27" which gives a 10% reserve at an indicated empty.
My theory is that the capacitance senders need to be clean to work properly and over time diesel oil deposits have fouled them. (See pic.) The floats are very simple. The downside I think is the level may bounce a little as I travel in rough water. I'll take that over guessing, I'm done with that! EZ to get at the senders on the 41 BTW.
My Fuel gauges on my 41 PC have never worked very well since I've owned the boat. Indicated full might be full and indicated 1/4 might be empty and empty might be empty etc.. Basically I've been keeping track on cruises by run time Almost screwed up two years ago and ran pretty low on the port side because I forgot to account for generator run time.
The gauges want to "see" 33 to 240 ohms range from full to empty. The senders have high and low limit potentiometer adjustment and I screwed around with them and I couldn't get them into range. The stock senders measure the capacitance of the fuel by running a small current from one isolated plate to another and turning it into a resistance electronically. Very accurate but a little complicated. I'm allergic to complicated.
I purchased two float style senders from WEMA I think about $60 each. The tank is 30" deep and the stock sensors are 27" which gives a 10% reserve at an indicated empty.
My theory is that the capacitance senders need to be clean to work properly and over time diesel oil deposits have fouled them. (See pic.) The floats are very simple. The downside I think is the level may bounce a little as I travel in rough water. I'll take that over guessing, I'm done with that! EZ to get at the senders on the 41 BTW.
