Bendix or slick mags

How to keep the Cessna 170 flying and airworthy.

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daedaluscan
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Bendix or slick mags

Post by daedaluscan »

Can anyone give me the relative merits of Bendix or Slick mags.

Just replacing my high time O-300 with a 600 hour motor that has Bendix mags. I had my Slicks rebuilt about 100 hours ago and am wondering if I should put them on the new motor?
Charlie

1956 170B C-GDRG #27019
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DoubleOught
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Re: Bendix or slick mags

Post by DoubleOught »

I've heard for the last 20-25 years that Bendix was a better mag than Slick. I just had my Bendix rebuilt put them back on in Oct. 2019.
I used QAA in Oklahoma 877-833-6948 , it cost $2150.00, they work great, they were about 10 years TBO. cant remember the hours.
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cessna170bdriver
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Re: Bendix or slick mags

Post by cessna170bdriver »

In about 2000 hours of flying Bendix mags on my 170 I’ve had exactly one mag failure. It was about 25 years ago, but I’m fairly sure the pair was past the recommended 500-hour inspection interval.
Miles

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Bruce Fenstermacher
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Re: Bendix or slick mags

Post by Bruce Fenstermacher »

BOTH mags are fine. You are opening a Ford vs Chevy discussion.

Bendix is not a better mag than Slick. I would not say Slick is a better mag than Bendix either.

For the record the only mag I've personally had fail is a Bendix.

Yet now that I'm working daily on mainly Cirrus SR20/22 and other newer larger Continental powered airframes, I've seen plenty of Slick failures. The last one a 3/4 million dollar SR 22 with 7 hours since new. Thing is we don't see many Bendix mags today on new stuff cause engine manufacturers don't use them.

How many hours on the Bendix? 600? I might swap in your 100hr Slicks as they've been inspected more recently.
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GAHorn
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Re: Bendix or slick mags

Post by GAHorn »

Historically, Slick was a cheaper alternative to Bendix and the reason it was cheaper was because lower-grade materials were utilized in it’s construction. Also historically, except for the one model of engine (the O-300-C) Continental chose Bendix for the factory magneto on O-300 engines.
To accurately discuss the comparison the particular MODEL of magneto should be mentioned. Some of the Slicks were built so inexpensively that they were referred to as “Throw-Away-Slicks” because they were not rebuildable. Bendix, on the other hand has been the standard to which to be compared, have always been repairable/rebuildable.
Yes, the Bendix units have more Service Bulletins and AD notes, and that has been a selling-point for Slicks, but that is because the Bendix units last longer in service while Slicks have had to resort to discontinuation of more models, lack of parts, and lack of repair schemes/support.
Having said that, I’ve got Bendix on my 170 and Slick on my 172 both with O-300 Continentals. The magneto failures suffered by individuals are only anecdotal, not dependable data. My anecdote is one failure of Slick and one Bendix, neither of which were installed on an O-300.
Both have better reputations than Eisemann. :lol:
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mit
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Re: Bendix or slick mags

Post by mit »

Bendix...…………...
Tim
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Bruce Fenstermacher
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Re: Bendix or slick mags

Post by Bruce Fenstermacher »

Eisemann, Eisemann, Slick, Ford, Bendix, Chevy.. :? Woops.
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170C
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Re: Bendix or slick mags

Post by 170C »

Don't forget those reliable CASE mags!

Speaking of magnetos, I have had excellent success having my Bendix mags inspected and repaired as needed (IRAN I think is the military term) and my alternator at Select Aircraft Services in Lancaster, TX (KLNC). Aaron Williams has always done good work and at fair prices for me. However, Aaron has closed his shop to pursue another aviation endeavor. He has recommended a shop , Aircraft Ignition Services in Honey Grove, TX 903-378-7205). I have no experience with this business and understand it was once located at Love Field in Dallas. I thought it might be time to ask our members for recommendations for shops that do this type of work. I am just short of 100 hours before needed my third 500 hour inspection and would like to have some options.
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mit
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Re: Bendix or slick mags

Post by mit »

Bruce Fenstermacher wrote:Eisemann, Eisemann, Slick, Ford, Bendix, Chevy.. :? Woops.
Bendix :)
Tim
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GAHorn
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Re: Bendix or slick mags

Post by GAHorn »

170C wrote:Don't forget those reliable CASE mags!

.
....and Fairbanks, AmericanBosch and Scintilla (and Lucas for those old Gypsies.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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