Help with access to holding tank sensors on 2004 Winn 40AD

[Big Bear]

My in tank sensors have gotten to the unusable point. I believe tank cleaning chemicals have finally corrected the gray tank, but the black tank has not responded. At some point I would like to install the Sea Level?? electronic sensors but not today. I Know how these sensors are installed as I replaced them on my 1st Winnebago. I was going to pull the old sensors out & clean or replace them for now. I need some advise on getting to them, I know where they are but cannot remove the access panel covering them in the service bay. It is the top panel of three and after removing all the screws I find that this panel is spot welded to the left hand support bracket. I can see the welds which were done before being painted. There are about 6 welds and considered drilling them out, but the top two do not allow enough room to get to them. I don't believe I am overlooking anything. If someone has done this on their own unit, PLEASE pass on any tips/help you may have.

Vern Phoenix
2004 Vectra 40 AD Cummins 350 W/Banks power package
2004 PT Cruiser, GT, Turbo, w/5 speed
Blue Ox Avanta 3 & Blue Ox tow plate W/Brake Buddy
Good Sam, long time Thousand Trails, & . FMCA

[Clay L]

I would call Winnebago customer service and ask them about access. I find it difficult to believe a panel is spot welded on after installation of the sensors.

I can tell you they use a very aggressive black caulk/adhesive behind some of the access panels. I had to use a flat pry tool to pry the edge of my access panel out a little and then use a knife to cut the stuff as I pried the panel out. It holds so tightly that it could easily be mistaken for being welded.

Note that replacing the sensors or cleaning them is not a solution. The problem is due to dirty tank walls gunked up with stufff that holds moisture and fools the sensors. Anything you can do to clean the tank walls will help.

Along with the Sealevel system there are some sensors out now that are long and stick out quite a ways past the tank wall and have the sensing element protected until out on the end. Thsi keeps the sensors isolated from the gunk on the tank wall. I have read some good reports on them. They are the Horst Miracle Probes.

[Big Bear]

Thanks for the quick reply. I am aware of the black sealant sometimes used, BUT this is for sure a spot weld problem. I can see & feel the small round depressions from the welds. I did call Winnebago and asked if possibly the top & center panel were welded to the left hand bracket as an assembly aid. They could not answer but said I might just have to remove BOTH panels as well as the left side bracket. The bracket is sealed (black stuff) & screwed to the inside of the sheet metal surrounding the compartment opening. Even then I think it would be VERY difficult to remove both panels and the bracket as a unit, not to mention having to remove/disconnect all plumbing & elect. going to the center panel. I will look at the Horst Miracle Probes, sounds like a good Idea. I was aware of the "coating" in the tank that can give bad readings. Just am hoping some one who has done this before has an answer.