TWinter Posted March 3, 2018 Report Posted March 3, 2018 Been a maintenance month for 7741M. Seems like lately every trip I've been scrubbed for one reason or another. I've searched some for the part number and I'm seeing various threads and not sure I'm finding the right answer. I went up last night and lost a alternator belt about 10 miles from home. I thought I would get one ordered and headed this way so my IA can get started next week, but want to make sure I'm getting the correct one. These pics are what was left of the one I had on it. I think the correct one is: 37A19773-376 LYCOMING ALTERNATOR DRIVE BELT .380 WID Part #: 08-00249 Spruce Am I looking at the correct one? Here are pics for reference I also notice some movement in the alternator when I move it my hand..about a quarter to half inch movement when pushing around near the bottom. Bottom looks tight and safety wire is still instact...normal or possible broke upper mount? Just inquiring out my own curiosity, I'm sure we will see the cause when he takes the front cowl off. You cant see it in the pictures, but the alternator is Electrosystems Inc. From what I can tell doing some cross-referencing it should be ALY-8420L S Really just checking if this is the right belt? Thanks much in advance.. -Tom Quote
TWinter Posted March 4, 2018 Author Report Posted March 4, 2018 53 minutes ago, Cyril Gibb said: is that safety wire on backwards? Don't know, but I asked about info on the correct belt? Quote
Yetti Posted March 4, 2018 Report Posted March 4, 2018 Search for Gates. I think you find that Gates number is also available at NAPA 1 Quote
TWinter Posted March 4, 2018 Author Report Posted March 4, 2018 1 minute ago, Yetti said: Search for Gates. I think you find that Gates number is also available at NAPA Thank you sir!! -Tom Quote
Yetti Posted March 4, 2018 Report Posted March 4, 2018 Looks like we have the same alternator. My Belt number. 1 Quote
flyboy0681 Posted March 4, 2018 Report Posted March 4, 2018 4 hours ago, TWinter said: I'm sure our European and Australian friends are laughing their asses off looking at those numbers, 1/8, 1/4, 7/8... Quote
Mjknick@gmail.com Posted March 4, 2018 Report Posted March 4, 2018 Sent from my iPhone using Tapatalk Quote
Mjknick@gmail.com Posted March 4, 2018 Report Posted March 4, 2018 -376 is oneSent from my iPhone using Tapatalk Quote
carusoam Posted March 5, 2018 Report Posted March 5, 2018 TW, Do you have a logged record of what was put on when the alternator was installed? There is probably a p/n in the log. I like the Yetti method of sharing p/n data. Right there mounted in place! The Gates number and other manufacturers’ numbers probably need to be crossreferenced via the Internet.... Best regards, -a- Quote
Yetti Posted March 5, 2018 Report Posted March 5, 2018 1973 E probably came from the factory with an alternator 1 Quote
TWinter Posted March 5, 2018 Author Report Posted March 5, 2018 E had alternator.. I was able to locate the overhaul date for the alternator in the logs 92'. Still no reference to a belt. I've poured through 2 service manuals and found nearly every part and manufacturer #. I'm sure I'm just overlooking, but thanks to Yetti progress is moving forward. Thanks for the info. -Tom 1 Quote
Stephen Skinner Posted March 5, 2018 Report Posted March 5, 2018 On 3/3/2018 at 3:15 PM, TWinter said: I also notice some movement in the alternator when I move it my hand..about a quarter to half inch movement when pushing around near the bottom. Bottom looks tight and safety wire is still instact...normal or possible broke upper mount? Just inquiring out my own curiosity, I'm sure we will see the cause when he takes the front cowl off. Hi Tom, if your alternator is moving around, check the upper mounts. My upper mount broke in-flight due to being loose for too long. In the end it was due to the wrong type of hardware being used. I posted pictures last April if you look under my profile you will see the results. The root cause was old Teflon locking style nuts. In my Journey logbook was 3 entry's of this being tightened over 10 years at annual inspections. It was overlooked on the annual before. The warn alternator belt may be linked to the movement of the alternator causing a miss alignment. 1 1 Quote
cliffy Posted March 5, 2018 Report Posted March 5, 2018 If the alternator is loose, something is wrong. It should be tight. Upper mount on the crankcase may possibly be broken. Mine was! 1 Quote
Guest Posted March 5, 2018 Report Posted March 5, 2018 A broken Lycoming mount, or loose bushings in the Prestolite alternator mounting tabs are quite common. Clarence Quote
TWinter Posted March 6, 2018 Author Report Posted March 6, 2018 Shop got to it today. I have not seen it, but apparently was missing a bolt and other was loose. I'm sure all the repeated cranking starts during my SOS issues did not help. They said the adjustment bracket was worn as well from the excessive play. Went ahead and replaced all of the components. Preventative maintenance. Replacing alternator (last alternator overhaul was in 92), brackets, belts, mounting hardware and a fresh O-ring when they put the prop back on. I like the idea of attaching a spare belt behind. I purchased two belts. Overkill, but maybe this will last a while. Thanks for all the input and advice. -Tom 1 Quote
Yetti Posted March 6, 2018 Report Posted March 6, 2018 Mine had a through bolt on the bracket side. And then a castle nut. It was not shimmed correctly at all and loose so it was running at a wrong angle causing wear against the front baffle. The castle nut was a big pain to get cotter pinned. Not sure the through bolt is the proper way. Found lots of not proper things on the plane. 1 Quote
TWinter Posted March 9, 2018 Author Report Posted March 9, 2018 My local shop should be wrapping things up today and hopefully 41M will be back in the air this weekend with new alternator and belt. The shop had a little (well a lot) of trouble getting the prop bolts to break loose, not a uncommon problem. So in effort to not to run the bolts, nuts and thread they suggested I take it to Cody Stallings Prop Shop. It was about an hour and half drive to their shop in Arkansas, but well worth it. I called them ahead and they were waiting for me at the door. Felt like a doctor wheeling a patient in for surgery. Immediately they took the prop in and went to work on it.. Within an hour they had all new hardware installed, ADs updated, wrapped up and ready to take back to my home shop. Just wanted to give a shout out of thanks to Cody and his team for getting me in and out. It helped that Cody is a fellow Mooniac F owner and forum member here, but I really do think these guys are a first class prop shop going over and beyond. I highly recommend them.. -Tom Quote
MARZ Posted July 5, 2018 Report Posted July 5, 2018 On 3/4/2018 at 7:08 PM, Yetti said: For reference the 7375 shows the length of the belt (37.5) inches, the belt width is 1/2" I just replaced mine with assistance of an A&P / IA, and the measurement on the old belt came up to 36", but I have the Interav alternator. I found that the Gates XL 9360 (36") is the correct application for me, I also safety wired a spare for the next go round..... Quote
Yetti Posted July 6, 2018 Report Posted July 6, 2018 Looks like I have the ALY-8420 Alternator. I have tried to remember to keep a photo parts tag documentation when things are apart. I could probably run a shorter belt as I am at the end of the adjusting arm. a 36 inch belt would move it 3/4 of an inch. I carry one of these in the hat rack for friends. https://www.harborfreight.com/vibration-free-link-belt-43771.html Quote
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