carusoam Posted October 8, 2021 Report Share Posted October 8, 2021 The nylon gears start out bright white… and turn brown as if they have been baked… This is the side effects of ozone generated in the mag… oxidation over time… as the gear teeth brown and darken they get brittle and easily break off… then the ignition timing challenges begin to occur… So… toss out the brown ones… while you are in there… If you are not expecting white gears… They will look really nice too… they just aren’t. PP thoughts only, not a mechanic… Best regards, -a- Quote Link to comment Share on other sites More sharing options...
Bartman Posted October 8, 2021 Report Share Posted October 8, 2021 In 2009 my AI did the 500 hr dual magneto inspection at annual. It was an inexpensive and worked great until about 100 hours later when one of the gears shed some teeth in flight and I landed on one mag. Had to rent a car and leave the plane at an airport out of state and enjoyed worrying about that. The guy on the field was helpful and knew about the dual mag but we had to get one off the shelf for $ 2,100 to get me back in the air ASAP. I learned from that experience… 1 Quote Link to comment Share on other sites More sharing options...
mhrivnak Posted November 7, 2021 Report Share Posted November 7, 2021 I sent my Bendix 3000 series dual mag for its 500 hour IRAN a couple of weeks ago. I talked with two shops that my IA has good experiences with and recommended. They both service our dual mags, and they were both very helpful on the phone. They each estimated about $1k in parts and labor assuming no surprises. I picked the one with the shorter backlog, and it happened that they also are the shop who IRAN'd it last time when the plane had a different owner. Aircraft Systems Inc in Rockford IL. They charged me $625 in labor plus parts, for a total of $1115. That included replacing one of the two capacitors at $208. They turned it around in two days and were easy to work with. No website. (815) 399-0225 G&N Aircraft in Griffith IN. They had about a 2-week backlog. 2 Quote Link to comment Share on other sites More sharing options...
jetdriven Posted November 7, 2021 Report Share Posted November 7, 2021 On 9/16/2021 at 11:13 AM, EricJ said: I just sent mine to Kelly this past spring and have been happy with the results. Removing the vacuum pump makes it a reasonably easy job by Mooney standards. I sent the lid and harness in at the same time with the mag and it all came back essentially new, even though it was a 500-hour inspection. No complaints here. As far as I can tell only Kelly (and maybe QAA?) service the dual mags. Everybody who used to seems to not do them any more. If you are looking at somebody else, verify that they'll service dual mags before sending it, and then please pirep the results. Aero accessories of Van Nuys will do the 500 hour inspection on the dual mag. Do yourself a favor, however, and just get new capacitors with it. We had one fail 30 hours later and had to take the mag back back out and send it back off to get checked again. 1 Quote Link to comment Share on other sites More sharing options...
RobertGary1 Posted November 7, 2021 Report Share Posted November 7, 2021 From what I’ve read the problem with the dual mags seem to come from installation. Most NTSB reports read that they backed off the engine, loose bolts etc. Quote Link to comment Share on other sites More sharing options...
toto Posted November 7, 2021 Report Share Posted November 7, 2021 Since Kelly makes all of the components and even now the casing under PMA, I would think that a lot of the smaller shops could do the dual mag IRANs again. Assuming they can buy all of the parts from Kelly. Quote Link to comment Share on other sites More sharing options...
EricJ Posted November 7, 2021 Report Share Posted November 7, 2021 3 hours ago, jetdriven said: Aero accessories of Van Nuys will do the 500 hour inspection on the dual mag. Do yourself a favor, however, and just get new capacitors with it. We had one fail 30 hours later and had to take the mag back back out and send it back off to get checked again. And the gears. They can fail suddenly due to age. Kelly includes new caps/condensers in their 500-hour cost, so that's nice. Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted November 7, 2021 Report Share Posted November 7, 2021 The last mine failed, it was a gear, but not what y’all are saying. On mine the distributor arm slipped. The shop said they have been seeing a rash of slipping arms. When I asked why, he said he has no clue. Quote Link to comment Share on other sites More sharing options...
jetdriven Posted November 7, 2021 Report Share Posted November 7, 2021 whats a distributor arm Quote Link to comment Share on other sites More sharing options...
EricJ Posted November 7, 2021 Report Share Posted November 7, 2021 (edited) 1 hour ago, jetdriven said: whats a distributor arm Here's a pertinent article with some pics that show the gear with the arm. The gear rotates so that the arm reaches the lead of the appropriate spark plug wire when it fires. If the gear teeth break or the arm slips, the arm won't be in the right location when the spark fires and either won't conduct the spark or send it to the wrong lead or to the wrong place. http://crossfiremagneto.com/Crossfire_Magneto_Service/Welcome_5.html Edited November 7, 2021 by EricJ 1 1 Quote Link to comment Share on other sites More sharing options...
FLYFST Posted November 23, 2021 Report Share Posted November 23, 2021 Someone mentioned Crossfire Magneto Service in Florida. Anyone tried them yet? ClarenceThey overhauled my D3000 in 2019 and I was very pleased with the results and with their communications before and after, as well as the detailed instructions provided to my maintenance shop for installation and check out.HankSent from my iPhone using Tapatalk Quote Link to comment Share on other sites More sharing options...
laytonl Posted November 24, 2021 Report Share Posted November 24, 2021 I used Kelly a couple of years ago. Good service and turn around time. No issues with the mag. Lee Quote Link to comment Share on other sites More sharing options...
larrynimmo Posted November 24, 2021 Author Report Share Posted November 24, 2021 Just for the record, Kelly was much more expensive than I expected, mainly because they condemned both coils as “cracked”. They were very quick getting the mag back to me….however, while they replaced the points, the two mags were not synchronized so, it had to be removed again after install. previous mag went for 450hrs on a Lycomming factory rebuilt engine… with rebuilt mag, I am getting about 50 degrees cooler EGTs, better lean of peak power and MPg…. with the old mag, we checked timing every annual and it was good…not sure what factor is producing the engine performance changes. spark plugs were not changed (tempest fine wire) only cleaned. Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted November 24, 2021 Report Share Posted November 24, 2021 2 hours ago, larrynimmo said: Just for the record, Kelly was much more expensive than I expected, mainly because they condemned both coils as “cracked”. They were very quick getting the mag back to me….however, while they replaced the points, the two mags were not synchronized so, it had to be removed again after install. previous mag went for 450hrs on a Lycomming factory rebuilt engine… with rebuilt mag, I am getting about 50 degrees cooler EGTs, better lean of peak power and MPg…. with the old mag, we checked timing every annual and it was good…not sure what factor is producing the engine performance changes. spark plugs were not changed (tempest fine wire) only cleaned. I’ve never gotten a dual mag back from service that was synchronized to my standards. I always reset the points so they both fire right at the E-Gap mark +- nothing. It takes a while to do it, that’s probably why they don’t. You end up with slightly different point gaps, but there is an allowable range. As long as you are in the range you are good to go. The engine runs better when they are synced. 1 Quote Link to comment Share on other sites More sharing options...
flyboy0681 Posted November 24, 2021 Report Share Posted November 24, 2021 Our shop sent it out to T&W (http://www.twaircraftelectrical.com/) for the 500 hour. Total was $1,900. Quote Link to comment Share on other sites More sharing options...
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