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Need help w/Fuel tank sender possible weeping screw

j-red

Well Known Member
Doing the first annual since putting this rv6a back online. There were no apparent leaks before this, but this year’s annual revealed some blue staining around the sender after I took the wing root fairing off. It appears to me that the leak is just a weeping screw based on the pattern of the stain and the gummyness of the pro seal around that screw. Then again, the pro seal that has been touched by the fuel is also soft enough that I can scratch it off with my finger in places.

If it is the screw, can I just drain the tanks, wait for it to dry, and apply some new sealer after scraping the old stuff off? Is there anything else that might work better for this application than proseal? Wicking loctite?
Or does it look like I’m going to have to pull the tank and remove the sender and do the whole thing?

(don't know why Halie keeps rotating the pictures, but the bottom of the wing is to the bottom right corner of the photo. The screw where the stains appear to be starting is at about 4:00 if you were looking head on to the sender panel)
odu.jpg

odt.jpg
 
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Don't pull the tank!
Is it the sender, or the access plate?
I just did this on my 6A. You can remove the sender from the root. You wouldn't think so, but it was quite easy. Plenty of room.
I purchased a right angle ratcheting screw driver on Amazon:
https://www.amazon.com/gp/product/B01IROWGOI/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

The screws came out very easily (I did make a little "button" to put over the back of the bit so I could keep pressure on the screw while extracting, but it probably wasn't necessary).

You can remove the whole sender (after removing the electrical wire, of course) and clean it up on the bench.
It it is the access plate, you can then remove that.

I was dreading it, but it was no harder than changing the oil. Mixed up the little proseal kit, put it back in with socket-head cap screws, and... no leaks!

(I am sweating the other one though, it has a flop tube and the sender on the rear baffle...)
 
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weeping screw replacement

Had this weeping screw issue come up an my RV6, as well as another on the field. The solution that worked was to replace the weeping screws with some "Very Special" screws that have a tiny O'ring under the head!
I'm not at the hanger now, so I can't give you the part number now,( maybe someone else knows?) If memory serves, they came from McMaster Carr.
 
Here you go:
https://www.permatex.com/products/gasketing/permatex-permashield-fuel-resistant-gasket-dressing-flange-sealant/

Intended for flanges (will work to reseal the sender, if needed), but you can put a fat dollop on/in the screw hole, and run the screw back in. Be sure to clean the screw well (acetone, etc) prior to inserting the screw. Be sure the sealant oozes out around the screw head when you tighten.

I've been using it on my tanks for several years. I've had several more proseal leaks in that time, but never a leak where I used this stuff.

Available at the nearest auto parts store.

Charlie
 
I did a similar thing on my (former) RV4. I removed the leaky screw, cleaned the area around the screw very well, and installed a new screw. I put pro seal in the screw hole, on the screw shank, and a dollop over the installed screw. No more leak. Let it cure for a few days, longer if it's cold, before filling the tank.
 
I would clean up the loose paint and anything else around the screw and wipe down with acetone. Then simply add a little pro seal over the screw area.
 
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