Recently I finished a swap on my -3 from an o290D2 to an O320 A1A. Battery stayed up in front of the rudder pedals. On the last few flights it feels much more nose heavy and my aft trim is not as affective as before (obviously it’s heavier!). I’m wondering if I am supposed to move the battery location behind the seat? Or ballast?
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RV-3 with O320 Battery placement or ballast
- Thread starter MoonDog1
- Start date
It’s up to you of course, but yes, we have our battery behind the seat in our IO-320 RV-3. We fly just aft of the center of the CG box solo with full fuel.
Would you happen to have any pics of the battery or install? Also, I used your picture of the throttle quadrant for replication in my own 3! With good success
. Had another issue today… low oil temp (116F @ 65%). I removed the shutter during the install. Looks like I need to either reinstall or tape the cooler.
Honestly, finding a picture would take a lot f time…that was a long time ago! We built a fairly complicated tray for the PC680 laying down, then a cover for it so that you don’t throw baggage directly on the battery. You might get a good result (CG-wise) putting an EarthX battery in the forward position - lighter overall, and simpler construction.
Our -3 has always cooled well, s yea - you might want a block-off in winter.
Our -3 has always cooled well, s yea - you might want a block-off in winter.
highflight42x
Well Known Member
I've got an O-320-D2G with 3 blade Catto on my RV3. Battery (PC680) has always been behind the seat, on its side, terminals fwd. No CG problems.
For the battery box, just search on "battery box for a PC680" and look at the "bevinsee" item, "Battery Box Mount Mounting Bracket For PC680 Odyssey" - looks like $35.99. That's the one I used.
I've got a #2 cable series going from the battery to the starter (sorry, no photo). It's got to be a heavier cable to carry enough current for the starter (I might have gone overboard with the #2 size cable). Master solenoid next to the battery. It's kind of a long route for the cable - from the battery to the master solenoid, through the aft cockpit bulkhead (rt side), behind the side cockpit panel, through the main spar bulkheads, fwd past the rt rudder pedal, through the firewall, to the starter solenoid and then to the starter. Ground cable is easy: just bolt from the battery to the baggage compartment floor.
Oh, and I get low oil temps as well: oil cooler about 80% blocked off in the back, Anti-Splat shutter in front fully closed: I consistently get oil temps = ground ambient + 100 (degF). I even put airflow restrictors on the front air intakes in winter - about 30% of the intake is blocked off. The vernatherm at the filter (rated to expand at 185degF) isn't closing, so very little oil is going out to the cooler. Yet I still get these mild oil temperatures. Go figure! To guard against corrosion, I put an engine dehydrator on it after every flight - replace all the hot wet air in the crankcase with cool dry air - and change oil every 25 hours or four months, whichever comes first.
Hope this helps!
- Steven
(1700 RV3 hours - another one last Thursday!)
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Thank you so much!! I feel much better reading this. It’s been doom and gloom recently with my RV. But it seems like I am not alone! Both ideas in this thread are excellent. I will experiment with both!!
Thank you so much!! I feel much better reading this. It’s been doom and gloom recently with my RV. But it seems like I am not alone! Both ideas in this thread are excellent. I will experiment with both
this seems like the quickest fix. Odyssey battery appears to be 3x the weight of an earth X. Will make the swap then go from there!
Here is my RV3A battery placement behind seat. I did not build this aircraft although I am in processing of resurrecting it.
(I have a luggage tray above this compartment that is closed off by the seat back so luggage doesn't interfere with battery or rudder cables.)
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Awesome. This helps a lot if I go this route. Will most likely try Earth X first. As this is the easiest swap.
Moondog, have you done a weight and balance? That should be your guide for this.
The plans, which are available on thumb drive I think, details a battery compartment in the baggage. Of course that's for the heavier heritage batteries, not the light weight lithium.
I am putting an EarthX 680C in the RH cowl cheek extension, just behind the cheek bulkhead. It fits but not with a lot of room. I had to make a hatch for it. The project hasn't flown yet and I haven't got a weight and balance yet.
Dave
The plans, which are available on thumb drive I think, details a battery compartment in the baggage. Of course that's for the heavier heritage batteries, not the light weight lithium.
I am putting an EarthX 680C in the RH cowl cheek extension, just behind the cheek bulkhead. It fits but not with a lot of room. I had to make a hatch for it. The project hasn't flown yet and I haven't got a weight and balance yet.
Dave
Unfortunately no I have not. That would be the smart and prudent think to do wouldn’t it? Lol. It’s in the plans just have to wait for a friend to help out. Either way I think I’m going with the earth-X. Half the weight double the cranking power. Impressive. Next problem is the Oil being way too cool. I tested probe and even used thermometer on oil and cross checked. Seems like an improperly functioning vernatherm if I was to guess. The oil cooler is taped half way.
sansoneservices
Well Known Member
If your current battery is lead, try a lithium battery in the current location
oaklandaviator
Well Known Member
When we refurbished our -3 we keep the battery in the back because the original box install was gorgeous. Still went with EarthX because of the weight savings though.
As for low oil temps, we have the same issue. I hadn’t thought about the 100• plus ambient but that seems about right. Blocking the oil cooler doesn’t seem to change anything.
As for low oil temps, we have the same issue. I hadn’t thought about the 100• plus ambient but that seems about right. Blocking the oil cooler doesn’t seem to change anything.
