Plastic Fuel Tank Leak from Sending Unit

Apr 26, 2014
34
Beneteau Oceanis 36cc Everett
I had to remove the sending unit from Beneteau 36cc which has a plastic fuel tank. The reason for removal is irrelevant at this point, but after replacing the gasket and reinstalling the unit it has leaked ever time I filled up the tank. Is there a special gasket? Or perhaps a sealant that can be used to seal this tank back up? Being a plastic tank, I can not torque the screws very hard as it would simply strip out the holes. Here is a photo of sending unit with wire connectors removed and the top plate next to the unit.
20180723_154522.jpg
 

NYSail

.
Jan 6, 2006
3,137
Beneteau 423 Mt. Sinai, NY
I am following this as I worry about same thing. I had to remove the sending unit a few times and always worry about the seal as like you said can’t really over tighten the screws. So far so good...... however I worry when filling. I would almost think on these tanks there would be something like butyl tape.... obviously would have to be made to withstand fuel.....

Greg
 

Gunni

.
Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
That is a one-use compression gasket, you need to replace it, not reuse it. Don’t goop it up with anything either.
 

NYSail

.
Jan 6, 2006
3,137
Beneteau 423 Mt. Sinai, NY
Wonder where one would get replacement gaskets....... get the sender model and call manufacturer or I assume one could be made using a basic fuel friendly gasket material from an auto store....

Greg
 
Apr 26, 2014
34
Beneteau Oceanis 36cc Everett
Yes, I did replace with a new gasket from NAPA auto parts, not a OEM part. Perhaps the original was more of a soft, thicker material?
 
Apr 26, 2014
34
Beneteau Oceanis 36cc Everett
After reinstalling I applied Permatex Ultra Black around the outside of base. It did seal the around the outside of base, and think that did not leak. I believe the fuel was actually coming up around the screws. So, I am going to get a new dry gasket and apply a small amount to gasket and screw threads prior to screwing down.
Wonder where one would get replacement gaskets....... get the sender model and call manufacturer or I assume one could be made using a basic fuel friendly gasket material from an auto store....

Greg
Dealer has not been very helpful. Will try again today with phone call. He has referred me to a boat yard in the area who also is not been helpful.