Master Relay or Solenoid, Battery contactor

How to keep the Cessna 170 flying and airworthy.

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cessna170bdriver
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Joined: Mon Apr 22, 2002 5:13 pm

Re: Master Relay or Solenoid, Battery contactor

Post by cessna170bdriver »

The big load is starter current, several hundred amps. Everything else is in the noise.
Miles

“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
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pojawis
Posts: 111
Joined: Fri Aug 01, 2003 10:51 pm

Re: Master Relay or Solenoid, Battery contactor

Post by pojawis »

Very good and timely information, for me at least. THANKS. Saved a bunch of time on my part.

Found two solenoids from Wicks Aircraft. One is listed as a starter intermittent solenoid, p/n 24037, $19.95. The other as a master continuous solenoid, p/n 24115, $23.55. The descriptions cover both and indicate these are Cole Hersee solenoids. No indication of PMA. I have not verified that this is a correct replacement for the 170...
pmel22
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Joined: Sat Sep 22, 2012 12:21 am

Re: Master Relay or Solenoid, Battery contactor

Post by pmel22 »

I replaced my old relay with a sky-tec sts-m12 in June, and it has now failed. I put in a call to Hartzell lets see what they have to say.
pmel22
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Joined: Sat Sep 22, 2012 12:21 am

Re: Master Relay or Solenoid, Battery contactor

Post by pmel22 »

Caution there is a service bulletin on the STS-M12, and it requires replacement.
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lowNslow
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Re: Master Relay or Solenoid, Battery contactor

Post by lowNslow »

Here is the link to the aforementioned SB. Tried to upload it but it exceeded the 1MB limit.
http://skytec.aero/wp-content/uploads/2 ... SB-072.pdf
Karl
'53 170B N3158B SN:25400
ASW-20BL
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Ryan Smith
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Re: Master Relay or Solenoid, Battery contactor

Post by Ryan Smith »

Is there a source for the clear plastic covers, or are these unobtanium?
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Bruce Fenstermacher
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Re: Master Relay or Solenoid, Battery contactor

Post by Bruce Fenstermacher »

You can find them right next to assist straps and instrument overlay rings. Keep you eyes open I've found all three.
IMG_1213.jpg
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Ryan Smith
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Re: Master Relay or Solenoid, Battery contactor

Post by Ryan Smith »

Bruce Fenstermacher wrote:You can find them right next to assist straps and instrument overlay rings. Keep you eyes open I've found all three.
IMG_1213.jpg
Any tips would be appreciated. It doesn’t appear that it has a part number?
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cessna170bdriver
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Joined: Mon Apr 22, 2002 5:13 pm

Re: Master Relay or Solenoid, Battery contactor

Post by cessna170bdriver »

I’ve lost track of how many years my master contractor cover has been missing. It doesn’t seem to be a problem.
Miles

“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
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