6 posts / 0 new
Last post
Last seen: 1 week 6 days ago
Joined: 1/11/19
Posts: 12
Fuel Level Sender

1995 Catalina 36 mkii..

Fuel level has never registered. I went by West Marine and picked up another sender that matched the one in the boat.. This one.. 


After installing the sender, it still didn't fix the problem.. I tried checking the gauge and it seemed to be functiing properly. According to my multi-meter the sender didn't seem to be working properly, so I took it back to West Marine and swapped it out for another one..  The second one didn't seem to work either according to my multi-meter, but then I decided that maybe I wasn't using my multi-meter properly. I then ran out of time, put it all back together still not working and came back home..

I called Catalina Direct and they said they didn't know of any Catalina sailboat that used a fuel sender with a return fuel port on it.. There have been many other owners prior to me, so I have no idea what has happened in the past with my boat. Does anyone else have a Catalina 36mkii that has a sender with a fuel return port?

Just to confirm, assuming that my boat has a stock Catalina gauge, should the above sender work? I guess I need to dig into the fuel tank compartment and see how the return fuel line is plumbed. I see the stock 25 gallon tank is suppose to have a return fuel port on the tank, not the sender, so not exactly sure why someone would have purchased this type of sener and then go to the trouble of plumbing a return fuel line to the sender, rather than direct to the tank..???????????????

Can anyone help me understand what might be going on??


Joe - SV Makara...

Joe - -
Mobile, AL.
S.V. Makara
1995 Catalina 36 MkII - Hull #1401 

Image icon Fuel Return Sender.jpg1.32 MB
Joe - -
Mobile, AL.
S.V. Makara
1995 Catalina 36 MkII - Hull #1401 
Last seen: 3 months 3 weeks ago
Joined: 2/15/10
Posts: 4

Have you verified the ground lead is in fact connected to you battery return?


Ralph Fagan
Terra Nova Yacht Club
Family Time
1995 C36 MK2 #1440

KevinLenard's picture
Last seen: 3 days 20 hours ago
Joined: 1/28/15
Posts: 141

Looks a lot like a PO decided to drill the return hole and install the 90 degree elbow into the gauge's brass plate instead of into the top of the tank.  Maybe it was a way to do the work without the risk of a spark blowing up the fuel?  At any rate, my problem with a non-functional gauge, after much cross-checking, was just the float in contact with the output tube -- it wasn't pointing in a direction that allowed it to float freely. 


Kevin Lenard
'91 C-36 Tall Rig, Fin Keel, Hull #1120, Universal M-35 original (not "A" or "B")
CBYC, Scarborough, Ontario, Canada

LeslieTroyer's picture
Last seen: 6 days 11 hours ago
Joined: 3/13/16
Posts: 494

I agree with Ralph. Double check the ground wire is under one of the screws for the sender unit and crimp is good.  


Les & Trish Troyer
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor. 



Last seen: 1 week 6 days ago
Joined: 1/11/19
Posts: 12

Oh the joys of owning a sailboat that has been owed by several others over the last 25 years.........................

Well turns out the fuel return port on the sender wasn't actually plumbed to return fuel to the tanks. I traced the hose and it was about 2 ft. long and was ziptied to other wiring in the top part of the port lazerette. The other end of the hose was just open. I have no idea why that sender was used..

I then replaced the sender with a nice reed style from Catalina Direct, hoping that it might fix the problem, but I wanted to get rid of the sender with return fuel port anyway.

What the heck, it still didn't fix my problem with always showing a full tank.  I spent hours trying to figure out what was going on. I followed all of the recommended troubleshooting information and all of the tests showed that the sender should work, the gauge should work and all the wiring tested good.

DRUM ROLL!!!! I finally discovered that when 12 volts was applied to the "I" post of the gauge, suddendly I would see continuity between the Sender post and the Ground post. That didn't seem right, so I replaced the gauge and now all is good. It's strange that I couldn't find anyone reporting this type of problem. Lots of info on the sender wire shorting to ground, or bad ground connection, ect.. I also found it very strange that continuity between the Ground and Sender only existed when power was applied to the gauge..

So if anyone ever has a deal like this, maybe check and make sure the gauge isn't showing continuity between G and S when power is applied (before) you spend hours tracing and making sure all the wiring is good. Now I just need to repack my boat and get it all put back together.

Joe - SV Makara

Joe - -
Mobile, AL.
S.V. Makara
1995 Catalina 36 MkII - Hull #1401 
Haro's picture
Last seen: 2 days 19 hours ago
Joined: 11/7/14
Posts: 259

That is a good test. I had a sender problem as well, but it was intermittent. I removed both sender and gauge and wired separately with 12 V battery. I replaced the sender with one where there is a donut shape ring that travels up along a pipe that is placed inside the tank.

Log in or register to post comments