leadsledfan
New member
A couple observations on my recent alternator install on my 1957 14-19-2 with the O-470k:
The Generator on my bird continually threw belts (about every 3-4 hours), somewhat obnoxious on long trips. I first thought that the bearings in the Generator were bad, checked out fine. Then I noticed the pulleys were misaligned, and that the pulley on the Generator looked fairly new. I figured the Pulled had been replaced with a non-stock part, leading to the misalignment.
Anyways, my proposed solution was to replace the Generator with a Plane Power Alternator. Saves weight, fixes the misalignment, no more brownouts on the radios, etc. The conversion kit was $756 at Aircraft Spruce. Not too Shabby in airplane money.
A couple of key things you will need:
20ft of 18AWG shielded wire, 10ft of 16AWG Shielded wire, 10ft of 8AWG shielded wire (for hot power line), a 60 Amp circuit breaker, and a new Mitchell 60-0-60 60 Amp Ammeter.
The alternator is rated to 70 amps, and that was my initial plan, but the 60 Amp Ammeter was $42, and the 80 Amp Ammeter was $230. Easy choice.
On the install: Not quite that simple.
The large nut holding the old Generator bracket can only be undone with a crows foot (Socket is blocked by the bracket), it took a crows foot, 2 12 inch extensions, and a 3 foot breaker bar to get it loose. Good luck. Luckily the new bracket does not block that nut, and it can be re-installed with a socket. (Thank you plane power)
The bolt holding on the lower brace below the accessory pulley is about 5 inches long. The distance from the Bolt head to the Firewall is about 3 inches. The only way to remove and re-install this bolt is by pulling the engine mounts and swinging the entire engine forward. I did not see this one coming.
The Lower Support bracket has two holes (For different engine set-ups). The instructions dictate using the Smaller of the two. Neither hole will line up correctly, and the hole must be elongated about 1/4 inch to fit. .
After these hurdles have been surmounted, the install is fairly simple mechanically, unbolt old bracket, bolt on new bracket. Unbolt old tensioner bracket and lower brace, bolt on new tensioner bracket and (Modified) lower brace. Bolt on alternator. Install Belt. Safety Wire.
The new regulator has a different mounting pattern, and required me to drill one hole in the firewall. No big deal.
As for Electrical :shock: :
The wiring in my bird was worthless. Shielding falling off, spliced etc. It was also undersized for 60Amp output. I started with the plan of using as much of the wiring as possible.
I ended up having to replace every single wire to or from the alternator, circuit breaker, Ammeter, Power Bus, and Battery Terminal.
But, after it was all said and done, the install is much cleaner and nicer than previous. Copious amounts of Zip-Ties, Shrink Tubing, and Ring Terminals were used. Oh Joy.
Also, I don't know how 8 Gauge wire shielding is supposed to be removed for grounding, but expect to lose some wire in failed attempts.
As a side adventure, I removed approximately 20-30 feet of old wire, much of which just simply didn't go anywhere. Wire from old gauges, old sensors, old instruments, etc. Probably saved 4-5 pounds in wire alone. I couldn't believe how much old crap was just terminated and left.
This involved being upside down, back cracked over the seat, landing gear handle in my spine, for about 8-10 hours.
Well, now it's done! Yay! I originally thought it would take 6-8 hours to install the new system. It took me roughly 25 hours to do it right. Time well spent in my opinion, but still a significant amount of time. I would NOT pay a shop to do this. The bill would be sky-high.
IF I knew then what I knew now, I would have looked for a higher output Generator option. Unless you are already planning on pulling the motor forward, and doing a ton of wiring, it just isn't worth the extra 35 amps. Power draw reduction measures like LED landing lights, LED Nav lights, an LED Rotating beacon and strobe, etc., would be much easier, and likely less costly.
Oh, and as for that Misalignment issue? The new alternator had the exact same problem! roughly 1 inch misalignment from pulley to pulley. Why, you might ask?
The main accessory pulley was INSTALLED BACKWARDS. You also cannot remove this pulley without pulling the engine forward, so this was likely done by the last shop that overhauled it. A quick google search of an O-470k revealed that the pulley was installed incorrectly (Dish was facing towards the engine, dish should be facing towards the firewall). The source of my problems all along was likely a hasty install by some mechanic. A quick fix since I already had the engine forward, but impossible to fix with the engine installed. Oh well. You live and you learn.
So that is my observations on an Alternator conversion.
Is it done? Yes.
Did it fix the brownouts? Yes.
Was it a PAIN IN THE ***? Yes.
Was it worth it? Probably. If only for the experience.
Good luck to anyone else who is undertaking this endeavor!
Oh, and I have a perfectly good Generator if anyone needs one.
-Adam
The Generator on my bird continually threw belts (about every 3-4 hours), somewhat obnoxious on long trips. I first thought that the bearings in the Generator were bad, checked out fine. Then I noticed the pulleys were misaligned, and that the pulley on the Generator looked fairly new. I figured the Pulled had been replaced with a non-stock part, leading to the misalignment.
Anyways, my proposed solution was to replace the Generator with a Plane Power Alternator. Saves weight, fixes the misalignment, no more brownouts on the radios, etc. The conversion kit was $756 at Aircraft Spruce. Not too Shabby in airplane money.
A couple of key things you will need:
20ft of 18AWG shielded wire, 10ft of 16AWG Shielded wire, 10ft of 8AWG shielded wire (for hot power line), a 60 Amp circuit breaker, and a new Mitchell 60-0-60 60 Amp Ammeter.
The alternator is rated to 70 amps, and that was my initial plan, but the 60 Amp Ammeter was $42, and the 80 Amp Ammeter was $230. Easy choice.
On the install: Not quite that simple.
The large nut holding the old Generator bracket can only be undone with a crows foot (Socket is blocked by the bracket), it took a crows foot, 2 12 inch extensions, and a 3 foot breaker bar to get it loose. Good luck. Luckily the new bracket does not block that nut, and it can be re-installed with a socket. (Thank you plane power)
The bolt holding on the lower brace below the accessory pulley is about 5 inches long. The distance from the Bolt head to the Firewall is about 3 inches. The only way to remove and re-install this bolt is by pulling the engine mounts and swinging the entire engine forward. I did not see this one coming.
The Lower Support bracket has two holes (For different engine set-ups). The instructions dictate using the Smaller of the two. Neither hole will line up correctly, and the hole must be elongated about 1/4 inch to fit. .
After these hurdles have been surmounted, the install is fairly simple mechanically, unbolt old bracket, bolt on new bracket. Unbolt old tensioner bracket and lower brace, bolt on new tensioner bracket and (Modified) lower brace. Bolt on alternator. Install Belt. Safety Wire.
The new regulator has a different mounting pattern, and required me to drill one hole in the firewall. No big deal.
As for Electrical :shock: :
The wiring in my bird was worthless. Shielding falling off, spliced etc. It was also undersized for 60Amp output. I started with the plan of using as much of the wiring as possible.
I ended up having to replace every single wire to or from the alternator, circuit breaker, Ammeter, Power Bus, and Battery Terminal.
But, after it was all said and done, the install is much cleaner and nicer than previous. Copious amounts of Zip-Ties, Shrink Tubing, and Ring Terminals were used. Oh Joy.
Also, I don't know how 8 Gauge wire shielding is supposed to be removed for grounding, but expect to lose some wire in failed attempts.
As a side adventure, I removed approximately 20-30 feet of old wire, much of which just simply didn't go anywhere. Wire from old gauges, old sensors, old instruments, etc. Probably saved 4-5 pounds in wire alone. I couldn't believe how much old crap was just terminated and left.
This involved being upside down, back cracked over the seat, landing gear handle in my spine, for about 8-10 hours.
Well, now it's done! Yay! I originally thought it would take 6-8 hours to install the new system. It took me roughly 25 hours to do it right. Time well spent in my opinion, but still a significant amount of time. I would NOT pay a shop to do this. The bill would be sky-high.
IF I knew then what I knew now, I would have looked for a higher output Generator option. Unless you are already planning on pulling the motor forward, and doing a ton of wiring, it just isn't worth the extra 35 amps. Power draw reduction measures like LED landing lights, LED Nav lights, an LED Rotating beacon and strobe, etc., would be much easier, and likely less costly.
Oh, and as for that Misalignment issue? The new alternator had the exact same problem! roughly 1 inch misalignment from pulley to pulley. Why, you might ask?
The main accessory pulley was INSTALLED BACKWARDS. You also cannot remove this pulley without pulling the engine forward, so this was likely done by the last shop that overhauled it. A quick google search of an O-470k revealed that the pulley was installed incorrectly (Dish was facing towards the engine, dish should be facing towards the firewall). The source of my problems all along was likely a hasty install by some mechanic. A quick fix since I already had the engine forward, but impossible to fix with the engine installed. Oh well. You live and you learn.
So that is my observations on an Alternator conversion.
Is it done? Yes.
Did it fix the brownouts? Yes.
Was it a PAIN IN THE ***? Yes.
Was it worth it? Probably. If only for the experience.
Good luck to anyone else who is undertaking this endeavor!
Oh, and I have a perfectly good Generator if anyone needs one.
-Adam
