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Does anyone have information on the subject kit? From the PA22 Univair parts book it appears that it included a starter button and solenoid to replace direct contact button switch in early PA22's. My original button has been disassembled a couple of times to polish the contacts. I want to upgrade it during rebuild and am trying to minimize IA paperwork. I have the Svenn STC for the battery and his master relay and starter solenoid is another option. The STC doesn't address the alternator switch that is part of the double pole master switch in the original. It would require separate field switch unless the STC Is deviated to use a separate master switch circuit breaker and a double pole master. It would be a good way to get rid of 65 year old electrical components. The only drawback I see to Svenn is a little extra current draw for the master solenoid (and a faster way to a dead battery if the master switch is left on). Info and comments of experience are appreciated.
Brian put Svenn's STC in mine and we just installed a separate switch for the field.
I did it that way when the alternator was installed so I kept it that way.
I retained the double pole master and installed a circuit breaker switch on the alternator field.
Steve,
Did you install the circuit breaker switch on the alternator field to gain independent control of the alternator or to add circuit protection to the field? Neither the original circuit diagram or my Inter Av alternator circuit uses a fuse or breaker on the field wire. The alternator installation uses an over voltage relay with a 5 amp circuit breaker.
I wanted to be able to turn the alternator off. Actually I don't turn it on until I have started the engine. My procedure is to turn on the master, start and then turn on avionics and alternator.
I installed the Sven battery master - starter solenoid STC and used a circuit breaker switch for the alternator field. I have mounted this next to the master switch \ circuit breaker. The STC works well but I have had some reliability issues with the Skytech solenoid.
I installed the Sven battery master - starter solenoid STC and used a circuit breaker switch for the alternator field. I have mounted this next to the master switch \ circuit breaker. The STC works well but I have had some reliability issues with the Skytech solenoid.
Interesting. Thanks for that. It was actually the starter solenoid that had to be replaced initially (by the time I had it fitted and tested in the aircraft it was out of its 1 year warentee, so I was out of luck), but the master has also stuck a few times.
Thanks for the good comments. I will be using Svenn's STC to add the master and starter solenoids, and add a separate circuit breaker switch for the alternator field. FYI, Spruce's stock of Sky Tec master solenoids was received the first week of this year per telephone call today. Since the Hartzell service bulletin is dated October 2017, I hope the problem is resolved and corrected.
Early last summer I replaced my starter solenoid with a skytek STS-S12 which doesn't appear to be on the list of those effected by the SB. I specifically replaced it with the skytek because the other brand one I had was sticking occasionally and everyone here said the skytek was the best. After reading above I was worried that I was back in the same boat again.
However once I got into it I discovered that my plane had the wrong one installed originally. It had a "continuous duty" on the starter solenoid where it should have had a "intermittent duty". The ID is beefier and can handle the huge current rush a starter gets. No issues since we installed it but it's not been that long ago.