Clean belly...

denverpilot

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DenverPilot
Not mine, the airplane’s. Ugh that’s so much work. But satisfying.

Noticed some paint blistering and peeling from leakage from the silly Cessna battery box drain. Guess we are going to have to get after that.

Understanding it always depends on the damage level, what’s the “typical” fix for that, oh wise maintenance people?

Clean off any more blistering paint, stop/neutralize any more acid of course, and then what? Do folks usually just have a little area stripped and primered and painted like a car, or...

How about areas around rivets? I see a little paint damage near a few. Hopefully superficial and not messing with the rivets. Nothing looked awful but there’s some exposed aluminum right behind the battery drain and little dribbles further aft.

(Guess I should clean the belly more often to see these things but that’s not going to happen, so, here we are. :) )

Just curious what the PoA crowd says. Obviously we’ll also consult our friendly neighborhood A&Ps also.

Just figured it was worth asking what’s usually “up” with damage behind the stupidly placed battery box drain. (Since it’s right on a rivet line. Brilliant, Cessna.)

Anyway. Belly is clean, Nate is dirty, and it was more fun than working on the cars, which also need some stuff done.

Also cleaned the slow incessant nose strut leak crud off of the nosegear arms and that area. It’d been a couple of years and that was just nasty. It never seems to get bad enough to need to rebuild the strut but man does the fluid slowly make a freaking sticky black mess.

We have a little nosewheel wobble and the plane will probably go into the shop to figure out if it’s nosewheel balance or whatever, so I figured the mechanic would prefer to be able to actually SEE the linkage and all that instead of a black covered mess.

Which then led to... well, while I’m under here and already dirty...

Now she’s ready for a proper bath and wax job. This was just getting the major belly grime off. Which is always a nasty chore.
 
Sell it and buy the Frankenkota. Concorde already installed.
 
Time to get rid of that flooded lead acid (Gill?) and get a Concorde sealed AGM battery!!!
That's one way to handle it. The other is to actually read the Gill manual and stop refilling those cells right up to the split ring unless the battery is on charge and actively gassing off. That split ring is the absolute max that the electrolyte should ever reach, not the level to fill it to when it's just sitting there doing nothing. Charging it creates gas bubbles in it and heats it, both of which expand its volume. It reaches above the split and the gas then has no escape so it shoves the acid out the cap and makes that horrible mess and eats aluminum.

Here. Page 17. www.gillbatteries.com/Content/PDFs/flooded_service_manual.pdf

Overfilling it does more than eat the airplane. It dilutes the acid. The battery blows out acid, it gets topped with water, it blows acid out again, more water is added, and so on. Soon that battery is shot. Adding water is intended to replace water lost to evaporation and gases created by electrolysis.
 
That's one way to handle it. The other is to actually read the Gill manual and stop refilling those cells right up to the split ring unless the battery is on charge and actively gassing off. That split ring is the absolute max that the electrolyte should ever reach, not the level to fill it to when it's just sitting there doing nothing. Charging it creates gas bubbles in it and heats it, both of which expand its volume. It reaches above the split and the gas then has no escape so it shoves the acid out the cap and makes that horrible mess and eats aluminum.

Here. Page 17. www.gillbatteries.com/Content/PDFs/flooded_service_manual.pdf

Overfilling it does more than eat the airplane. It dilutes the acid. The battery blows out acid, it gets topped with water, it blows acid out again, more water is added, and so on. Soon that battery is shot. Adding water is intended to replace water lost to evaporation and gases created by electrolysis.

Good tip. Not sure our mechanics would appreciate us giving them a lecture though, since they always know everything. For the record, we haven’t done any of the battery filling on any battery in the last ten years in this particular airplane.

I’ll fill the car batteries. I don’t mess with it out of the airplane or crammed in that little space inside the airplane. Well worth the hourly rate to not deal with that. Or spills. Although who knows, maybe a spill is how this started. There’s always been a little bit of this behind the battery vent on this particular airplane. Just seems like it’s a “little worse” for this particular belly cleaning.

Can’t really tell if that’s just time and elements or what but it’s definitely at the point I want to get it cleaned up “properly”.
 
Good tip. Not sure our mechanics would appreciate us giving them a lecture though, since they always know everything. For the record, we haven’t done any of the battery filling on any battery in the last ten years in this particular airplane.

I’ll fill the car batteries. I don’t mess with it out of the airplane or crammed in that little space inside the airplane. Well worth the hourly rate to not deal with that. Or spills. Although who knows, maybe a spill is how this started. There’s always been a little bit of this behind the battery vent on this particular airplane. Just seems like it’s a “little worse” for this particular belly cleaning.

Can’t really tell if that’s just time and elements or what but it’s definitely at the point I want to get it cleaned up “properly”.

It's not worth the hourly rate to have them ovefilling it, ruining both battery and airplane. Tell them that another mechanic said to read that manual and they'll have satisifed customers.

If I have to top a battery that isn't on charge, I add enough to get the electrolyte midway between the tops of the plates and the bottom of the split ring. Otherwise, I charge it and top it. I NEVER have acid in any battery boxes in any airplane I look after. No belly acid. Doing what Gill says really works.
 
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