Battery relocation
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
Battery relocation
Does anyone no of an STC to relocate the battery from the firewall to aft of the cabin on a Cessna 170B, I am installing an Airwolf oil filter on the firewall and need the room.
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Unless you're hanging more weight on the nose- big engine, c/s prop, etc- I'd be concerned about what's gonna happen to your CG when you relocate the battery aft. Can't help but cause the CG to move aft, perhaps enough to affect load-carrying ability. I'd want to keep the empty CG pretty much as far forward as possible.
Seems like mine has enough room on the firewall to mount a filter or chip detector somewhere without getting rid of the battery. Those devices are plumbed with hoses, so just where on the firewall shouldn't be too critical, eh?
Eric
Seems like mine has enough room on the firewall to mount a filter or chip detector somewhere without getting rid of the battery. Those devices are plumbed with hoses, so just where on the firewall shouldn't be too critical, eh?
Eric
Re: Battery relocation
no. But I have some comments:KENDRURY wrote:Does anyone no of an STC...
- you should be able to find room on your firewall without relocating the battery. It's been done many times before.
- moving the battery to the back adds several pounds of heavy gage wire to your airframe and will probably degrade your cranking power. That's why it's a popular mod on 180/185's to move the battery up to the firewall.
- IMO the Airwolf is a poor choice. You're adding 2 hoses and 4 connections to possibly fail on a critical system. Why not use a case mounted unit like the F&M?
- paul
I moved my battery back behind the baggage compartment and changed it from a 25 series to a 35 series for the extra capacity. The one positive power cable running forward to the starter doesn't add that much weight and the CG hasn't been a problem. In view of the fact that most of my flying is solo, I find that it is most helpful to have the extra weight in the rear. The airplane flys better and lands better. I used to carry a sand bag in the rear, when I was otherwise running empty, to improve the flight characteristics and landing CG.
I used the Del Air STC which cost $100, at that time, which included the plans.
I used the Del Air STC which cost $100, at that time, which included the plans.
BL
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battery relocation
I relocated my battery with Harry Delickers STC. You only add about 14ft of 00 wire. This does not add up to 20 lbs. I have a B&C light weight starter on my 0360 and it spins the hell out of the engine. There is no power loss by putting the battery back behind the passenger compartment. It also cleans up the engine compartment. Jon
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- cessna170bdriver
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- Joined: Mon Apr 22, 2002 5:13 pm
My stock B-model bumps up close to the forward limit when solo. It DEFINITELY lands better with someone in the back seat! I haven't run the numbers, but even with the battery in the back, as long as you don't load the back seat without loading both front seats, I don't think you'd run into an aft CG problem.blueldr wrote:I did move the battery back when I installed the IO-360 in that airplane. I needed it to get the CG within the envelope. In the stock airplane I moved it back to make it handle better. And it does.
Miles
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
There actually IS power lost thru the longer battery cables, but it's not likely to be significant if the connections are good and the battery is charged up. But a cold engine, and arctic night, and a hesitant start or two could prove troublesome.
I'd prefer and recommend the FM Enterprises filter over the Air Wolf, and avoid the problem and save a bunch of money also.
I'd prefer and recommend the FM Enterprises filter over the Air Wolf, and avoid the problem and save a bunch of money also.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
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battery relocation
Good to see Gahorn is still around to refute any advise I put on the site. Yes there is minimal loss in a longer cable, but if you have trouble starting with the longer cable, it will most likely be in the connections, the battery, or the starter itself. This is exactly why alot of people don't give any advise or help on this site! Good luck, Jon
Battery Relocation
I am confused Why would anyone even remotely consider putting a bag of sand or other ballast in their rear seat or baggage compartment to aid in landing a C-170 "To aid in landing" If a C-170 lands better with something/someone in the back seat, so be it, but I sure can't see why you competent pilots would need any help with our easy to land aircraft. I used to have a '64 C-182 and it, admittedly, was easier to land with two folks in the rear seat and/or baggage, but with the application of elevator trim it landed just fine with me or me and one front seat passenger. And this was with a Cont O-470 & CS Prop. just forward of the firewall. Just curious
OLE POKEY
170C
Director:
2012-2018
170C
Director:
2012-2018