Moneybox

I can carry out a load test once charged however that is not going to fix the alternator/charging problem. I have no doubt the battery may have lost some of its ability to supply a full discharge however it did fully charge after it was flattened. After I'd left the master on and found the battery flat it was fully charged. I left it at the door of Northam Air Services with a note requesting to have it charged. I picked it up a month or so later and it cranked the engine as if fully charged, not the sign of a stuffed battery.

There's no way of telling if the generator/alternator ever worked since I got the plane. It hasn't been used enough to tell and the generator light operates as if it's charging.

Yes I understand the battery may now be damaged however this is not a battery fault. I have no generator charge. I bought the battery new so about a year old but until completely flattened over several days it remained fully charged. It recharged fully after that so I'm hopeful the battery is ok. It may even improve with constant use.

Did that 9.8v same as battery voltage.

The plane has no volt meter or amp meter. I've checked it with the multimeter.

No, slight voltage decrease.

I planned on filling the tank as soon as I landed. I went down to the card operated bowser, the only 98 in town but it's out of order. It's already been reported but being out here repair might take some time. I do have 60L of fuel I changed out a month or two back, I could mix it with the half tank left.

Yes, I just came in from checking it out. 10v in the battery so I started it with the jumpstarter. The red generator light comes on with ignition as expected and goes out once started but there's absolutely no battery charge. 9.8v at 3000rpm.

Can somebody tell me how much charge I get from the 912 ULS alternator? How does that compare to the current drain to charge an iPhone 12 and a iPad series 6? I started out with a flat battery. My nice new Odyssey battery might be stuffed since I left the Master on a few weeks back. It's been charged and flown since but after standing for a couple of weeks it was too flat to crank. I took it out and put it on 6A charge for a few hours before putting it back in knowing it was not fully charged but I need to fly while the weather was in my favour and I expected the Rotax to charge it. This morning it fired up ok but after landing over 2 hrs flying when I stopped to refuel it was too flat to crank again. I'm charging the iPad and iPhone while I fly. I managed to reach up through the bottom hole on the cowl and attach a jumpstarter and flew off for another hour. Mid way the tacho shut down so I pulled the cigarette lighter plug and the tacho came good until the iPad dropped dead and I still had a long way to go so I plugged it back in. Once again the tacho dropped out so I continued on without it. I've only just arrived home so I haven't had a chance to put a meter on it but the charge light says the Rotax is charging.

I've just been in the air for a little over 3hrs and to be honest I could have done without a Manifold Pressure gauge. I used the variable pitch prop to avoid excessively high engine revs and I backed the throttle off by about a third to unload the engine. I can here the revs getting up into the yellow and I can hear it working unnecessarily hard. Variations in manifold pressure were next to nothing. I can't see the value in it.

Great document Skippy and I've worked out how reading it makes you engine last longer. The hours spent on reading are taking you away from flying therefore your engine lasts longer. 😀

My brother bought a 1970 Mazda Capella new, took it back for the first free service and never removed the drain plug after that. It lived for nearly 200,000km before it was sold. He said he saved a fortune on service costs.

If you just drive to the pub and back you should change your oil more often.

Hi Guys, help me out here. I've never had a manifold pressure gauge. I understand how it operates and I understand what it's reading but I don't know my best settings. When I'm cruising I have to adjust my propeller to a high pitch to prevent the engine running over maximum revs. What I don't understand is where my best/least fuel consumption comes from when matching RPM to Manifold Pressure while maintaining cruising speed. Lets say I want to keep the Rotax 912ULS spinning at 5000 revs while getting my best economical cruise speed. Do I control this with manifold pressure?

As long as it hasn’t been over tightened before you’ll most likely be able to reuse it. If you can’t get you hands on one and it’s solid metal it could be annealed and reused. My experience with purchasing Rotax parts is you could save a few bucks by buying an assortment box of sump plug washers from your local automotive part supply. If the washer has a neoprene seal inserted then a hydraulic parts supplier should have one.