What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

fuel sender

rwarre

Well Known Member
Replacing fuel senders in my rv7a but since I don't have a clue what fuel leaks with these sensors looks like, I would like some help to figure out where the fuel was coming from. I didn't use pro seal, just the rubber gasket the sensors came with(Stuwart Warner). The inside of the sender is clean so the only thing I can think of is that the fuel seeps through the threads on the screws. I have pictures but need help posting. Sorry that I am not technically literate.
 
Look for dark or blue stains around the edge or screw heads.

You could seal the screws by dabbing some proseal (or other proven sealant) under the heads before tightening them down.
 
using the rubber gasket just about guarantees leaks. Proseal with star washers between the plate and rib to give a gasket effect in the pro seal seems to work the best. I never use the rubber gaskets on the RV tanks.
It should be obvious where the leaks are.. If you use the rubber gaskets it will likely indicate seepage around the edges of the sending unit.

JIm Frisbie
RV 9A (950 hrs)
RV 10 under const.
 
Found some special screws at McMaster-Carr that have a sealing ring under the head of the screw. Have solved the seepage issue on my RV6, and a couple others as well.
 
Sad to say that the gasket provided with the fuel senders is not fuel proof, so throw it away. There is a Van's SB about it.
Proseal must be used to achieve an adequate seal. Don't tighten down on the screws and squeeze out all the proseal, leave them just a little slack until the pro-seal cures and then tighten. It is easiest to replace the senders with the tank off the aircraft in a cradle.
Pete
 
Let me preface my question with, "I'm new to the RV world." I keep seeing everyone say you have to proseal in your fuel senders and gaskets don't work. Why is this? I don't doubt the collective knowledge that it stops fuel leaks, but why are the screws and gasket not sufficient? I put the CiES senders in my Mooney with just the rubber gaskets and have no leaks, and plenty of others too. The Mooney also has a wet wing like the RVs. So why do RVs need to proseal in their senders? When I read these threads I feel like its band aiding the problem instead of solving it plus creating a maintenance nightmare in the future.

Sincerely,
A concerned builder waiting on his wing kit with fuel tanks that will need to be built.
 
Let me preface my question with, "I'm new to the RV world." I keep seeing everyone say you have to proseal in your fuel senders and gaskets don't work. Why is this? I don't doubt the collective knowledge that it stops fuel leaks, but why are the screws and gasket not sufficient? I put the CiES senders in my Mooney with just the rubber gaskets and have no leaks, and plenty of others too. The Mooney also has a wet wing like the RVs. So why do RVs need to proseal in their senders? When I read these threads I feel like its band aiding the problem instead of solving it plus creating a maintenance nightmare in the future.

Sincerely,
A concerned builder waiting on his wing kit with fuel tanks that will need to be built.

The short answer to why is that many of use have seen these gaskets leak. Not right away, but they will.

I fixed leaks on an RV-8 a few years ago, both senders installed with just the gaskets. They lasted about 15 years, but the 100LL eventually turned them to goo. If you must use a gasket, put proseal on both sides first.

Proseal is easy, and removing senders that are installed with proseal is not a big deal if you ever have to replace a sender (I never had the need).

Carl
 
Back
Top