No Power!

Paris12Man · #1 11-30-2016, 04:57 PM

Well, this evening I went out to the plane to put some fuel in for tomorrow's flight. I removed the fuel pump fuse (as I normally do) and turned on the master switch..........no power! I checked the Master Bus fuse and that is good. I cycled the switch a couple of times but to no avail.

I haven't taken anything apart yet. I wanted to get some ideas from you guys at what you think it might be.

I last flew on Saturday 11/25 and everything was fine. My battery is the original and is 5yrs 5mos old. I have been thinking of replacing, but I expected to get some warning of the battery going bad. Do they normally just die this sudden?

Thanks....

JBPILOT · #2 11-30-2016, 05:05 PM

Take top cowl off and check battery volts. If dead, charge it and see what you get. Report what this gets you.

Mich48041 · #3 11-30-2016, 05:34 PM

My PC680 developed an open circuit due to a faulty internal weld. I posted the symptoms on the AeroElectric List and Bob Nuckolls asked me to send the battery to him for analysis. He cut the battery open and found the bad weld. The battery was 6 years old, but still cranked the engine just fine up until it failed suddenly. You can read Bob Nuckolls report HERE.

Paris12Man · #4 11-30-2016, 05:49 PM

Thank you John and Joe for your suggestions....

I found the problem on my second visit to the airplane. I have added a 12 volt port in the back of the airplane for use by my ADS-B device

. It's controlled by a simple on/off switch located by the standard 12 volt outlet in the plane. Last flight my passenger was last to get out and he must have hit the switch to the "on" position therefore draining my battery

.

My battery was discharged down to 7 volts. I now have it on a charger and hopefully in the early morning it will turn over the engine

.

sblack · #5 11-30-2016, 09:22 PM

Why do you remove the fuel pump fuse?

turbo · #6 12-01-2016, 06:45 AM

the battery owes you nothing at this point. might as well replace it now or at least do a load test on it.

LettersFromFlyoverCountry · #7 12-01-2016, 08:40 AM

Quote:

Originally Posted by sblack

Why do you remove the fuel pump fuse?

This is also my question as I'm considering building an RV-12 and wondering if this is some sort of standard procedure.

snopercod · #8 12-01-2016, 08:53 AM

Considering the importance of your battery, I think you should change it now. Sure, they may last 5-7 years, but do you feel lucky? I change mine every three years regardless. It's one less thing to worry about.

JBPILOT · #9 12-01-2016, 09:04 AM

If you are use to the sound of a solid start, then you should realize the battery is losing power. Mine is now 7 years old and sounds very solid. I may get caught, but I just went thru the same thing with the wifes car. I could tell the starter was losing power, so I load tested it, and proved it was getting weak. If you want a safe test, turn on master and avionics and let it set for an hour. Then try to start it. If it sounds weak, maybe a good time to replace.

Mich48041 · #10 12-01-2016, 09:52 AM

Quote:

Why do you remove the fuel pump fuse?
This is also my question as I'm considering building an RV-12 and wondering if this is some sort of standard procedure.

Removing the fuel pump fuse is not standard procedure. There is no switch for the fuel pump (except for the master switch). Van's wants the electric pump to always run for safety reasons. It might be desired to shut off the noisy pump and avionics cooling fans, which are on the same circuit, while on the ground playing with the avionics or for some other reason.