I just got it fixed!

That sucks.
 
It always something. That really (doesn't) suck.
 
So you are at 8,000 ft, doing around 115 kts (indicated) and you are in a turn, climbing at 150 ft/minute,
and your battery is discharging, but it's not your alternator.

??
 
JOhnH said:
So you are at 8,000 ft, doing around 115 kts (indicated) and you are in a turn, climbing at 150 ft/minute,
and your battery is discharging, but it's not your alternator.

??
Click to expand...

Hint. Attitude Indicator tumbling, VAC light illuminated on annunciation panel.
 
Well that's (Atis, Landing checklist, Approach brief, Radios, Missed)-ing.
 
I had a similar experience with my Arrow this year, but on some level it was my own fault. My vacuum pump died, thankfully in VMC. I bought an overhauled one. When I called the dealer to pay for it, I made a mistake: I told him that it was the last vacuum pump that I would ever have to buy (since I'm building an RV and going with glass). The overhauled pump worked fine during ground testing including a series of high-power run-ups to balance the prop, which I had just had overhauled and put on the plane the week before the vacuum pump died.

After we buttoned the plane up from the prop balance and annual inspection, I taxied out for a test flight, did a run-up, and then pulled onto the runway and applied full power. Overheard in the cockpit: "Airspeed alive. Rotate. Seriously?!?!?" Apparently the overhauled vacuum pump was afraid of heights. I got the LOW VAC light just as I rotated. I promptly ordered a new vacuum pump, which cost something like 10% more than an overhauled one, and so far it's treated me well.

I also had to replace the right main tire tube twice in the same month this summer. I'm really hoping that the propeller and alternator do not meet a similar double-maintenance fate. These things are expensive enough to do once.
 
My dry pump had about 275 hours on it when the polyurethane shear coupling broke. It turns out those are "recommended" to replaced every three years IIRC. Put a new coupling on it and its been working great since.
 
BigBadLou said:
Look again.
This ain't no high-wing Cessna.
His charging indicator shows approx 15 amps (interpolated). *shrug*
Click to expand...
If it's charging 15A then he has a serious problem.
That's a load meter. The alternator is providing about 15A but very little of that should be going to the battery, it's mostly running the electrical system of the plane. When it hits 0 it's time to worry.
 
chartbundle said:
If it's charging 15A then he has a serious problem.
That's a load meter. The alternator is providing about 15A but very little of that should be going to the battery, it's mostly running the electrical system of the plane. When it hits 0 it's time to worry.
Click to expand...

Think all or most Cherokees show load. I demonstrate this to students by turning on something, like landing light, and watch the load increase. Yeah "0" indication would be find a runway quickly time.
 
JOhnH said:
So you are at 8,000 ft, doing around 115 kts (indicated) and you are in a turn, climbing at 150 ft/minute,
and your battery is discharging, but it's not your alternator.

??
Click to expand...

Look at the TC and the Vac annunciator. His vacuum pump isn't doing well, and according to the TC he is not turning and he is in coordinated flight.
 
As one would expect, it was the vacuum pump.

As to the electrical stuff, it's been working just fine since I replaced my defective replacement alternator. That ammeter reading is normal for this airplane, seems a completely reasonable amount of charge for position lights & beacon plus all the avionics to me.
 
cowman said:
As one would expect, it was the vacuum pump.

As to the electrical stuff, it's been working just fine since I replaced my defective replacement alternator. That ammeter reading is normal for this airplane, seems a completely reasonable amount of charge for position lights & beacon plus all the avionics to me.
Click to expand...
Might this be a good time to look to see if you can use a G5 to eliminate the need for vacuum?
(I hope this comment isn't as stupid as my last one was).
 
JOhnH said:
Might this be a good time to look to see if you can use a G5 to eliminate the need for vacuum?
(I hope this comment isn't as stupid as my last one was).
Click to expand...
It's always a good time to look at using a G5 and getting rid of the vacuum system. Those vacuum pumps really are out to get you. The upgrade is just an expensive proposition. A new vacuum pump and filters will cost you about $400 plus labor to install, and the labor is negligible if you do the knuckle-bruising and gymnastic routines yourself while the A&P watches and laughs at you. A dual G5 system, which may also require a new autopilot in some cases, will be more like $10,000 plus a whole lot of labor wiring things and working on the pitot and static systems.
 
I’m working on possibly buying a Lance in the next few months and then selling this plane so I don’t want to dump more money into the panel. Otherwise I might consider it.

As it is, this plane that’s been relatively trouble free for years sure seems to be finding expenses now that I’m looking at trading up.
 
cowman said:
I’m working on possibly buying a Lance in the next few months and then selling this plane so I don’t want to dump more money into the panel. Otherwise I might consider it.

As it is, this plane that’s been relatively trouble free for years sure seems to be finding expenses now that I’m looking at trading up.
Click to expand...
You didn't tell it you were thinking of trading up; did you? :eek2:
 
simtech said:
Where does one put a third G5?
Click to expand...
Turn Coordinator.
Although I'm not sure that meets the needs to entirely replace the Vacuum system(looks like a TC needs to be retained for IFR). Out of an abundance of caution I got a RC Allen Digital AI and battery to put in my TC spot(AC 91-75) for my eventual vacuum removal. Although I'm not sure if that meets the letter of the G5 STC either, but I'll see next year when I actually try the avionics upgrade project.
 
chartbundle said:
Turn Coordinator.
Although I'm not sure that meets the needs to entirely replace the Vacuum system(looks like a TC needs to be retained for IFR). Out of an abundance of caution I got a RC Allen Digital AI and battery to put in my TC spot(AC 91-75) for my eventual vacuum removal. Although I'm not sure if that meets the letter of the G5 STC either, but I'll see next year when I actually try the avionics upgrade project.
Click to expand...

The TC typically isn't a vacuum instrument. Electric gyro. And that level in it is needed to tell you if you are in coordinated flight or not.
 
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