Battery Location with Avcon 180hp conversion

[flyboy122]

Hi All,

I'm having more fun and adventure with the engine overhaul on my Avcon converted 170B. I installed a Casper Labs oil filter adapter on the back of the engine, and per the recommendation of a few other forum members I installed the 1.5" spacer to clear the engine mount. It does clear the mount nicely, but....it's pretty obvious this is going to interfere with the battery. On my airplane the battery is mounted top center on the firewall. Is there a different battery location I can use?

Thanks,
DEM

[DaveF]

On my Avcon conversion the battery is upper LH side of the firewall, aft of the oil cooler. It's a good location because there's plenty of space for the wiring and it's near the cowl access door. It's not good because the box is attached to the firewall on standoffs to clear the stiffeners, and the entire box has to be removed to pull the battery because of interference with the engine mount. I don't have a good picture of it right now, but I'll find one.

[GAHorn]

IF you want a baggage door.... now's the time to consider it and moving the battery aft of the baggage bulkhead a-la C-175. (If your baggage door and structure was obtained from a 175, and you wanted to move the battery then it would be a simple matter to take the battery box/mount also.)

[ghostflyer]

Putting the battery down the back also creates problems ,for example weight and balance. It would have to have a reweigh if the mod was done. then due to its being out of sight and mind it doesn't get looked at enough unless something goes wrong. try fitting a Odessey battery ,the 620 series.they have there own box also. they are a lot thinner and can be mounted on a angle also. I have the Harry Delicker STC and there would be could be differences between the this and the Avon mod. I have now a Concord Battery fitted with a standard box on the firewall.Its a real close fit but everything has a clearance. I have had trouble with the charging system and the Odessey battery. it wasn't charging properly for some reason . It didn't have enough grunt for starting always. We checked voltage output /amps etc of the alternator/regulator and have the heaviest leads etc but ??. tried the Concord no problems and over 120 starts since. But its still possible for the 180hp and the battery on the fire wall.

[Roesbery]

With the battery box mounted on the firewall aft of the oil cooler behind the motor mount, pretty much in the original position on the later models. Cut the end of the box and add a piano hinge across the bottom. Makes access to the battery simple with the bottom cowling removed.

[flyboy122]

I'd rather not do the aft battery right now. I'm really just trying to get the airplane flying with a minimum of fuss at this point. But I don't see any way the oil filter adapter will fit with the battery box in the top center location, unless I'm missing something. Some pics of those that have done it may really help so that I can see how it compares to my setup. That, or suggestions on another place under the cowl to locate the stock box. Thanks!

[GAHorn]

ghostflyer, it appears he has the Avcon conversion. ...and he wants to modify that with an oil filter adapater. ...and he wants to relocate his battery.
That means he already has a wt/bal/re-weigh problem so that should be no addt'l problem.

In fact, the chances are that merely installing a Concorde battery makes a wt/bal change since that battery weighs more than one pound different than original and therefore would require a wt/bal computational change.

BTW, on a similar subject, The arguments regarding whether or not an STC is required to install a Concorde in these airplanes appears to have become moot. The Concorde battery is now FAA-PMA and so the STC is not longer req'd for most aircraft. Additionally, AC 23-27 applies to our airplanes, so the STC is not req'd per that. And, finally, GILL is making a VRLA battery in competition with Concorde and it is also FAA-PMA and therefore is only a logbook entry by the owner/pilot.

[flyboy122]

Do I have a w&b problem? Well, when I picked up the airplane I discovered two 20lb shot bags in the baggage box left there by the previous owner when he parked it. So apparently he thought there was! I have a B&C starter which will take some weight off the nose, as well as about 900lbs of antique avionics that are destined for ebay. After that we'll see where the CG lies and look at mods from there.

FWIW, I bought an expensive sealed Gill for my PA12 and it lasted 1.5 years and was wonky for half that time. I bought an expensive sealed Concorde to replace it and it's been in there 6 plus and still going strong. I know what my 170 is getting.

In the meantime I just want to get thing up and running (with shot bags if necessary). I'd still really appreciate some pics of the battery boxes and/or oil filters on Avcon 170's. I'm at that point where I need to do the work and I'd appreciate any help I can get.

Thanks,
DEM

[hilltop170]

If you are using the sealed Concord or Odessey batteries, the battery box does not have to be level, it can be rotated to clear motor mounts, etc. Many C-180/185s have angled boxes and they work very well.

[ghostflyer]

When one of the members talked about putting his old radios on Ebay , I had a very old Collins BC-6** VHF radio that came out of the 170. there was 2 units to make up the radio and a loom . it weighed a heap. one day this old fellow banged on my hangar wall and asked me if I had any old radios. I was going to dump this radio. I showed it to him and told him its serviceable. he started to tremble and his eyes sparkled. How much ? make me a offer!! $250 cash. he thought it was Christmas.So did I. Both of us were very happy with the deal. he was a collector of old aircraft avionics. Sorry to stray off the original subject.

[JohnNielsen]

F. Atley Dodge STC for micro gel battery.
See attached pic.
John

[Blue4]

A lightweight 170 with the Avcon conversion can be particularly nose heavy -- that is, it tends to be at forward CG. This can make 3-point landings more difficult. As George suggested, an aft-battery conversion can be a good idea to help balance this equation. I've been told that the weight of the long 2-guage cable, though, can be significant. Numbers I've heard mentioned are 7 or 8 pounds! If you want to carry extra weight to balance your Avcon, throw something useful like a case of oil as far aft as you can carry it.

My Avcon battery is located below the oil cooler on the left hand side. It was nicely installed, but the complaint I have with it is that I must pull the entire cowling if I want to remove the battery. A solution to all of these problems is a lightweight sealed battery mounted such that it could be removed (and warmed or charged as needed) from only the access door. Lighter weight means better performance, and less weight forward of the datum reduces the nose-heavy CG tendency. Newer battery technology is a wonderful thing.

[GAHorn]

... If you want to carry extra weight to balance your Avcon, throw something useful like a case of oil as far aft as you can carry it......

If you don't have a big oil leaker.... I consider a more useful ballast system would be a case of bottled water...especially in a survival situation. (You might need to add a bit of it to the bourbon at the end of the trip.)

(Plus if it leaks it's no big deal, and if you need to get rid of it you haven't thrown anything expensive or hazardous away.)

[flyboy122]

Hi Guys,

I bought an Odyssey battery and just made a smaller battery box. It will mount in the same location (top center) and clear the Casper labs filter just fine. I'm kinda spent out so I wasn't too keen on another $150, but the old battery was probably on it's last legs anyway, and anything to get the weight off the nose is a good thing.

Now if I can just sell my PA-12 I'll be able to order the new cylinders, put her back together, and try all this wonderful new stuff!

DEM