Found a hairy growth on the bottom corner of the battery box. Cleaned it up and sprayed with some silicone. The battery seemed a little damp, I'm wondering if the box isn't draining properly. The POH mentions a clamp on the battery box drain that must be removed to drain the box, but I don't see one. Also wondering if the trickle charge I leave on the battery at night might be contributing to the moisture in the box.

My 1960 180 had the clamp in place when we removed the battery box for some maintenance and mods (Bogert battery box mod). The clamp is rectangular in shape with a sliding bar running between two sides pushed by a thumb screw running through one end. It hooks on a small rectangular bracket aft of the battery box on the outside of the brace (note the battery box support though) where the battery drain line leaves the box and goes under the brace to the drain/vent pipes.

We replaced our drain/vent lines while we had the battery box removed. In the process, we discovered the 3/8" metal drain pipe (the middle one) which exits the aircraft was completely clogged with corrosion material. It was very resistant to manual removal (stiff wire, drill bit, pick, compressed air). It took about 3 hours and 4 changes of a water/baking soda solution to dissolve the clog. I estimate the clog was about 3/4-1" long. One of the vent pipes was totally clogged with mud (most likely insect related) and the other was partially blocked.

Now, we have a freshly cleaned, painted, and modified battery box with new clear vent and drain lines. I did reinstall the clamp as well.

Michael

I'm not trying to be critical, but why are you putting a trickle charger on your battery? If you're flying the plane on some kind of regular basis, the battery is fully charged when you return. Unless there is a drain on the battery that exists after the master switch is shut down, the battery should be able to sit wihout any attention for several weeks without losing any discernable level of charge. If it can't, you either have a bad battery which needs replacement, or you have something hooked up that is bypassing the battery solenoid and putting a load on the battery. Either way, I would not use a trickle charger for my battery. A battery tender is a different animal, and might be acceptable under certain conditions.

Dave Gitelman

I forgot to add to my previous post that the clamp is necessary and should be inplace and closed while operating the plane.
Which means it is only opened when cleaning out the box, allowing any fluids to drain.

Dave Gitelman

Took the battery out yesterday, cleaned the box and vent and drain lines. Noticed a hole in the corner of the box, so I may look into a new box in the future. I'm also going to remove the charger and see how it does. I'll probably take the battery out during the winter months and charge it outside the A/C. Didn't have a clamp on the drain line .

Bogey Aviation makes new stainless steel battery boxes. Good units.

Agree with Dave's comments on a trickle charger. I do use a battery minder, which is a whole different deal.

Jay

All: I talked at OSH with the sealed (dry?) battery mfg. rep. I repeat his firm advice to me for your consideration: Early (5 years ago or so) "Battery Tender" maintenance chargers are OK with their sealed batteries, but later models were manufactured overseas and do not regulate properly to maintain their batteries, if left connected full time. "Battery Minder" chargers are fine for their dry batteries, and can be left connected full time.

I bought a "Battery Tender: some time ago. I am not sure where it was manufactured, but a sharp Electrical Engineer friend cautioned me about leaving it connected full time, and I just hook it up on occasion for a few hours when I am at the hangar. No problems.

Al Powers