Had an "experience" with Ole Pokey over the Labor Day weekend I won't soon forget. We, Becky & I, left Aledo, TX Friday am headed for Timberon, NM with a fuel stop in Snyder, TX (about my 6th or 8th time to stop there---really nice folks if you happen to be in the area). Left SNK and climbed up to 9500 ft between Hobbs, NM & Timberon. Noticed a little roughness a few times, but attributed it to being over desolate country & about to go over the mountains. Then noticed I was having to use full throttle to maintain 2500 rpm. Checked my mags & BEHOLD, left mag was dead. Now I am in the foothills with about 40 miles to go so decided to go on as I was able to coax Ole Pokey up to 10.5 & later to 11.0 (I like a lot of space between me & those rocks!). Made it into Alamogordo, NM only to find no one willing to lend assistance until Tuesday. I then began a frantic call to numerous of you to see what help I could find. Thanks to Tom Benedict in Roswell I made contact with two fellows, one in Sandia, NM & one in Deming, NM, both of whom were willing to help, but neither had but a few Bendix parts. Called Joe Harris in GP,TX and he did yomans service enlisting the help of George Horn, Wayne & Jody and others. Joe finally put his freshly overhauled mag on the Greyhound and it arrived on Sunday morning. Took it to the mechanic on Monday,but he wouldn't do anything until Tuesday am. THEN when he pulled the mag he discovered that the spring (p# 10-51324) in the impulse coupling had broken. Still not sure why the disabled impulse coupling kept the mag from working after the engine was started on the right mag, but it didn't anyway. Fortunately he had a new one (he had told me he didn't have coils, points, condenser, etc as he had converted all his planes to Slick mags), but as I said I got lucky & he had the spring. Installed it and fixed the problem. Lost an extra day + quite a bit of sleep, but neither is permanent. Don't know what caused the spring to break, but sure makes one think about getting some spare magneto parts to carry along on trips. That gurantees you won't need them!
Many thanks to all who assisted in trying to find parts, etc and especially to Joe Harris who interrupted his weekend to assist me. Thanks Joe! This 170 Assn has sure resulted in my meeting and making a lot of good friends.
Ole Pokey
Magneto Failure
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
You are VERY welcome Frank, it was a pleasure!
The aviation community - 170 part of it in particular - are amazing and wonderful people.
Right off the bat, we had a part number conflict given to us by the mechanic in NM. Called George to see if the two different part number mags were interchangeable and he said that he had a house guest and the book he needed was in the room they were sleeping in. He asked me to hold on, heard him open a door and then - loud female screaming what are you doing lifting my covers up? Just kidding, George gave us the info we needed. Then it was just amazing all of the help that was volunteered. Wayne and Jodi who are avid 170 fans volunteered an airline ticket if I wanted to fly the mag to El Paso. Billie, a hangar neighbor who built an RV6 volunteered to quickly fly us and the mag to NM, etc, etc, etc. Many people wanted to, did, and offered to help.
As fun as the flying is, it is difficult to say that it is more fun than the people associated with aviation.
The aviation community - 170 part of it in particular - are amazing and wonderful people.
Right off the bat, we had a part number conflict given to us by the mechanic in NM. Called George to see if the two different part number mags were interchangeable and he said that he had a house guest and the book he needed was in the room they were sleeping in. He asked me to hold on, heard him open a door and then - loud female screaming what are you doing lifting my covers up? Just kidding, George gave us the info we needed. Then it was just amazing all of the help that was volunteered. Wayne and Jodi who are avid 170 fans volunteered an airline ticket if I wanted to fly the mag to El Paso. Billie, a hangar neighbor who built an RV6 volunteered to quickly fly us and the mag to NM, etc, etc, etc. Many people wanted to, did, and offered to help.
As fun as the flying is, it is difficult to say that it is more fun than the people associated with aviation.
Joe
51 C170A
Grand Prairie, TX
51 C170A
Grand Prairie, TX
Magento's
With my recent experinece, now seems a good time to open the question of which mags are the best--Bendix or Slick---both from the cost, reliability and repairability aspects?
Don't know for sure how old my Bendix ones are as they were on my plane when purchased in 1989 & were tagged "Rebuilt". I had the coils, points, condenser, etc all replaced quite a number of years ago when the AD was out to ck on the coils, et al. Each has passed the impulse coupling checks thus far.
Give me some input. I don't know if mine need replacing, repairing or just continue using these old "tractor" ignition systems.
Ole Pokey
Don't know for sure how old my Bendix ones are as they were on my plane when purchased in 1989 & were tagged "Rebuilt". I had the coils, points, condenser, etc all replaced quite a number of years ago when the AD was out to ck on the coils, et al. Each has passed the impulse coupling checks thus far.
Give me some input. I don't know if mine need replacing, repairing or just continue using these old "tractor" ignition systems.
Ole Pokey
I do not have experience with Slicks, so others will have to inform us.
Recently built a Mag Maintenance binder. Researched AD's and Service Info. Only one recurring AD applies to my P/N 10-51365-39 Bendix mags and it is well documented in the Service Bulletin. In fact, there is a wealth of information available in Service Letters and Bulletins to help maintain the Bendix mags. Aircraft Spruce sells the parts.
Both Bendix and Slick manufacturers have documented several defects that can lead to magneto failure. Capacitor failure on the Bendix addressed in SB651 and bearing spinning in the end cap in Slicks addressed in AD/ELECT/46 as examples. There are many more for both brands.
Both Bendix and Slick manufactures reccommend internal inspection and repair at 500 hours.
The reputation I am hearing is that Bendix are more expensive and last longer. Slick is cheaper and has more of the market share. Slicks can effectively only be overhauled 2 or 3 times before replacement.
On both brands there is a decision of buying parts and repairing, or buying refurbished units at $400 - $500. Or, the expensive route of buying new.
Apparently on Frank's earlier question, if the impulse coupling rotates it causes the mag to fail. Still not clear exactly and doing further research.
Recently built a Mag Maintenance binder. Researched AD's and Service Info. Only one recurring AD applies to my P/N 10-51365-39 Bendix mags and it is well documented in the Service Bulletin. In fact, there is a wealth of information available in Service Letters and Bulletins to help maintain the Bendix mags. Aircraft Spruce sells the parts.
Both Bendix and Slick manufacturers have documented several defects that can lead to magneto failure. Capacitor failure on the Bendix addressed in SB651 and bearing spinning in the end cap in Slicks addressed in AD/ELECT/46 as examples. There are many more for both brands.
Both Bendix and Slick manufactures reccommend internal inspection and repair at 500 hours.
The reputation I am hearing is that Bendix are more expensive and last longer. Slick is cheaper and has more of the market share. Slicks can effectively only be overhauled 2 or 3 times before replacement.
On both brands there is a decision of buying parts and repairing, or buying refurbished units at $400 - $500. Or, the expensive route of buying new.
Apparently on Frank's earlier question, if the impulse coupling rotates it causes the mag to fail. Still not clear exactly and doing further research.
Joe
51 C170A
Grand Prairie, TX
51 C170A
Grand Prairie, TX