Battery relocation

[cmsusllc]

Annual time - removed battery due to some corrosion in the battery box. It was painted at some time inside but now there's corrosion underneith the paint. Removed the box to clean it up. I have a forward CG problem ( Avcon conversion ) so am looking at relocating the battery behind the baggage area. I reserched this forum and have the information on battery relocation from '2006'.Is this still good info. ( Del-Air STC ) ? Any other information?
Thanks for your help. Scott.....53B

[GAHorn]

It's a great time to also do the baggage-door mod (as it was for battery-access that Cessna created the baggage door.)

[cmsusllc]

Yea, but I've got a pair of those Alaskan jump seats that fold up out of the way so I don't need to go cutti'n holes in the side of my plane. Although if I still had the stock year seat I'd probably get the sawsall out.
Scott.....53B

[KS170A]

It's a great time to also do the baggage-door mod (as it was for battery-access that Cessna created the baggage door.)

Is the baggage door mod accomplished via STC or field approval?

[GAHorn]

It's a great time to also do the baggage-door mod (as it was for battery-access that Cessna created the baggage door.)

Is the baggage door mod accomplished via STC or field approval?

MIne was completed by Del Lehmann IAW Harry Dellicker's STC.

Del, holding the door & frame salvaged from a 172

Me, grinning from ear to ear

FredricksburgDOOR.JPG (37.69 KiB) Viewed 9893 times

[blueldr]

When I did the Continental IO-360 engine conversion, I moved the battery back on Harry Dellickers STC and changed it to a 35 size battery just for the slightly greater amp hours available when flying out in the boonies.

[cmsusllc]

I called Del-Air today, $ 170 for the STC
Scott.....53B

[Jr.CubBuilder]

I used the DelAir STC for that. It's essentially a couple pieces of aluminum to mount the battery box on top of. If you do the DelAir take a look at how it is open on one side under the battery box, and you might want to reinforce that just a tad with another right angle piece up to the bottom of the battery box. I land on some rough strips and I'm concerned that it flexes just a bit much.

[cmsusllc]

Thanks for the information, I'll keep it handy for when I do the actual instalation. Business is slower than heck so I'm not spending funds on anything I don't have to right now so I rebuilt the battery box. What I noticed was the design of the box on a taildragger allows acid to stand in the back of the box until you fly, when it can then drain out. I built up the back flat area with J B Weld so it will drain even when parked then painted the box. Hopefully this will get me by until I can get the relocation done.
Thanks, Scott.....53B

[Jr.CubBuilder]

Other than wishing that mount was a bit more rigid (not going to mess with it now that it's in there unless it needs fixing) I don't have any real complaints about the location. However, for what it's worth I would take a long look at potentially mounting a lighter battery on the firewall if I were making the decision again. My mechanic is doing an IO360 conversion on a 170 here and he ended up using an Atlee Dodge battery box for a smaller lighter battery, and it mounts at an angle on the firewall to avoid interference with motor mounts etc.

The DelAir conversion I did on the motor relocated the stock box to the top of the firewall as part of the STC, I got him to throw in the STC for the rear location also and moved it back there. Weight and balance wasn't that bad as it turned out, so I have had thoughts of moving it back to the firewall so I can get rid of the 10lbs of cable running back to it. It's worth spending some time crunching numbers on W&B combinations.

[GAHorn]

.... What I noticed was the design of the box on a taildragger allows acid to stand in the back of the box until you fly, when it can then drain out. ...

The bottom of the box should have a "bird-bath" funnel-shape to it's bottom to drain in normal attitudes. If your box has been replaced with a later box it may have a flatter bottom. But... in any case... acid in the bottom of the box should not exist at all, especially in a resting airplane. If the battery is not overserviced, and if the charging system is working properly a battery will not boil over.
If it does boil over because of the aforementioned problems, then it will do so only inflight...when the airplane is not sitting on it's tail anyway. (Of course, misted electrolyte may still be in there, and may migrate to the aft area of the box when parked. A good idea for that is to 1- be certain the box is painted internally with acid-proof paint, 2- sprinkle baking soda into the box-bottom before installing the battery (to neutralize any subsequent acid) 3- inspect the box for acid after a flight/every post-flight until the battery service-level/charging system is corrected (then clean it out with baking soda solution, dry it, and sprinkle fresh soda again.) After the problems are corrected it shouldn't require inspection again except as specified in the mx schedule.

(Cessna 100 Series Service manual specifies every 25 hrs or 30 days.)