IOWA'S 170

How to keep the Cessna 170 flying and airworthy.

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iowa
Posts: 664
Joined: Fri Sep 01, 2006 4:57 pm

Re: IOWA'S 170

Post by iowa »

Guess its a moot point now that I purchased the 355

...and thanks Hilltop for advise about the radio switch.
From now on, I'll leave the radio master off until the plane starts up.
...also, good idea about GPs, I won't retire my dad's Garmin 95 just yet

Was going to the Atlantic, Iowa flight breakfast this morning
but it was storming 8O
Bad as I couldn't go
Good as the crops really needed the rain!

Dave
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1951 170A 1468D SN 20051
1942 L-4B 2764C USAAC 43-572 (9433)
AME #17747
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GAHorn
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Re: IOWA'S 170

Post by GAHorn »

TSO is not required for “certified” aircraft….unless the owner or the operations require it. (I.E., not necessary for common Pt 91 ops.)
'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. ;)
iowa
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Joined: Fri Sep 01, 2006 4:57 pm

Re: IOWA'S 170

Post by iowa »

It has been awhile

My daughter is getting married this July 22
so i'm on my own for Oshkosh
as she'll be on her honeymoon

Having my annual performed at the moment
will be done this Friday i.e. 2 days

Found the L wingtip light is burned out
It is the Grimes A-7512-12 13v 26w 8019
Are these still available?
Does anyone use them anymore?
What should I use?

As always
Appreciate your help

Iowa
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1951 170A 1468D SN 20051
1942 L-4B 2764C USAAC 43-572 (9433)
AME #17747
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n2582d
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Re: IOWA'S 170

Post by n2582d »

Try calling Avlite Aviation. See if they have a better price than here at Aircraft Spruce.
Gary
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GAHorn
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Re: IOWA'S 170

Post by GAHorn »

'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. ;)
iowa
Posts: 664
Joined: Fri Sep 01, 2006 4:57 pm

Re: IOWA'S 170

Post by iowa »

Hello Everyone
Been awhile, but I'm back!

Bought a new Gil-25 battery for the 170

What charger should I buy to charge it up?
The instructions say to charge 12-13hr
Table says:
G-25 3 amps 30min 30 amps 1 hr 18 amps
And to use constant current charge rates

What does all this mean?
In the past I've always used a car battery charger at 6 amps

Thanks

Dave
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1951 170A 1468D SN 20051
1942 L-4B 2764C USAAC 43-572 (9433)
AME #17747
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Bruce Fenstermacher
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Re: IOWA'S 170

Post by Bruce Fenstermacher »

The Gill 28 is an 18 amp hour battery which means in theory if you put an 18 amp load on it, it would be totally dead in 1 hour. Like wise if the battery was totally dead, if you charged it at 18 amp for 1 our, it would be totally full. C-1 which is short for Charge 1 hour is then 18 amps. If you charged the battery at 36 amps for 1 hour you'd be charging at 2C or twice the C1 charge. If you charge at 9 amps for an our you'c be charging at 1/2C.

If your charger is not a constant charge type charger, you will not be able to charge at a constant amperage. As the battery gets full the voltage will go up and the amperage will come down. Most car battery chargers are not constant charge.

As you don't every want to completely drain your battery, you also do not want to over charge it. Over charging will boil the electrolyte out and the heat can warp the plates causing them to touch and short out.

When your Gill was shipped it was dry. Gill charges the battery then removes the electrolyte. When you refill the battery with electrolyte it will have a pretty good charge but it will not be topped off.

What Gill wants you to do is a low amperage long charge. This will slowly bring up the battery to full capacity without overcharging it.

They are looking for 10-12 hours. If C1 is 18 amps them 1.8 amps is 1/10C. This is so small it would be difficult to over charge the battery.
A fully charged Gill 12v battery should read 13-13.2 volts at rest. If it's less than 13v, you could be more charge in it. You could also test the specific gravity of the electrolyte. Aircraft use different electrolyte than car batteries. A fully charged aircraft battery including Gill will read 1.285. If your are using a car electrolyte tester this is just off the scale high if the highest line is 1.265 which is full car battery electrolyte. A really good tester will have a 1.285 line but not all.

I think I've covered about everything so now your an expert. But if you are like most you still don't know what to do.

Here is what I'd do. I assume you don't have a constant amp charger. You probably have a car battery charger. Hopefully your car charger as a low setting of 2 amps. Your fresh new battery with new full levels of electrolyte is probably 75% full. This means you need 4.5 amps more to top it off. Put the charger on the battery at 2 amps and come back to the battery in 3 hours. Turn of the charger and let the battery sit about 30 minutes. Use a volt meter to read the voltage across the terminals. If you have 13-13.2 v you are done. Or you could test the specific gravity for 1.285. If the battery is still low, charge it at 2 amps for another 2 hours and repeat measuring voltage or specific gravity. Make sure the electrolyte level stays at the correct spot or add distilled water to bring it back to correct level. You should have a fully charged battery by the time you get to 10 hours of charging. Remember you set this car charger at 2 amps but it's not really charging at 2 amps but less than 2 amps this is why it could take 10 hours total charge time.

If your car charger does not have a 2 amp setting you could use one with a higher setting but you need to fully understand everything I wrote here in the entire post to safely do it. For example if your battery charger only has a 6 amp rate, if it did charge at 6 amps you'd have a full battery in about 45 minutes. If you left it on charge for 3 hours, you are probably going to boil electrolyte out all over. Did I mention electrolyte gas is corrosive and explosive. And your battery will be hot.

Know this, you charge these batteries with the caps off or loose. You want to do it in a well vented area. Automatic Car battery chargers will not work properly on automatic on an aircraft battery because the characteristics of an aircraft battery are different than a car battery those the auto function are relying on to work automatically.
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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GAHorn
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Re: IOWA'S 170

Post by GAHorn »

I’ve used an ordinary, automatic automobile charger rated at 10A for almost 45 years without any ill effects on lead/acid/flooded aircraft batteries.
(It’s Schumacher brand with an analog charge-rate indicator. While modern equivalents are still priced below $75, I’d avoid any from Harbor Freight or any off-brands if you’re shopping.)

With a new battery such as a Gill “pink power”, my charger will indicate 5A or slightly more for the first charge period during installation. It will taper-off to below 2A within 30 mins, and taper to 0 after a few hours.

It’s my personal opinion that the hoopla about aircraft batteries being so-different from common lead/acid auto batteries is not particularly significant. I also believe that the great-concerns promoted by some aircraft battery mfr’s suggesting that only very expensive and specific battery-chargers can be used with VRLA or “sealed” batteries is a cry of “wolf”.

Here’s why I feel that way: Our airplanes were designed with low-amperage DC-Generator charging systems controlled with vibrating-points regulators. These systems are no more sophisticated than 1950’s/early ‘60s automotive electrical systems using flooded-cell lead/acid batteries.

The batteries used and approved for these airplanes must be capable of being managed by those basic-technology electrical systems. All modern aircraft batteries …(lead acid, VRLA, etc) …Must be capable and Compatible with the existing aircraft electrical-system design …to be approved for installation in our Cessna 170’s utilizing the original charging systems.

If these “modern” aircraft batteries were Not compatible and properly served by the original, crude charging systems in our airplanes…. then they would Not be “approved” for installation.

I’ve used Gill flooded cell and Concorde VRLA batteries in my airplanes over 40 years without any difficulty. I also keep them on inexpensive automotive battery “maintainers” continuously…(not “trickle-chargers”) …when sitting in the hangar for the last 20 years, also without any difficulty. (about $21 at WalMart) https://www.walmart.com/ip/EverStart-MA ... hEQAvD_BwE
IMG_3660.jpeg
My aircraft batteries typically last between 5 and 7 years between replacements.

(my comments reflect my own experience/opinion and should not be taken to be critical of the information others have offered)
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'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. ;)
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Joe Moilanen
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Re: IOWA'S 170

Post by Joe Moilanen »

My thoughts exactly George! A battery is a battery…As long as they’re not overcharged.
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GAHorn
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Re: IOWA'S 170

Post by GAHorn »

Joe Moilanen wrote: Fri Apr 11, 2025 5:56 pm My thoughts exactly George! A battery is a battery…As long as they’re not overcharged.
Hey Joe! I’m in Room 8 here at the asylum… which room are YOu in..??
'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. ;)
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Joe Moilanen
Posts: 605
Joined: Sun Dec 28, 2003 5:45 am

Re: IOWA'S 170

Post by Joe Moilanen »

:lol: I can’t remember George!!
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