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The pit falls of not following directions. Metal in the Engine

Kahuna

Moderatoring
There I was, listening to my engine idle with a rat a tat tat noise. Sounded much like an impulse coupler, which if I had any, I would have thought it was and never done a thing. But since I don't have any, time to figure out my new noise.
Im fortunate to have on my field, a retired 30 year NASCAR crew chief who has heard and seen it all when it comes to engines. He brought is handy noise tools and most importantly, his finely tuned ear. 'Hmmmm. Not heard that frequency before. Its in the accy case.' I dont like it when the expert is listening to my engine with a scowl and twisted face in confusion.:confused:
OK pull the filter and cut. Nothing too disturbing. A few fine flakes and with a magnifying glass, magnets, lights n things, we are not convinced there is a problem. But there is enough head scratching going on to warrant further inspection.
Next remove the finger screen. As the fitting comes off, metal parts start dropping out. AHHH! Thats not good.
OK engine comes off. Sump off, accy case off. All on the bench in 1.5 hours. Found the culprit. A Magneto Bearing.
If you were a right side up only flyer, this bearing would just drop in the sump and sit there for many years to come without much fan fare. Me, well, not so much. So the bearing had the opportunity to traverse the sump and accy case enough to smash it to pieces. Enough to break a tooth off the idler gear for the right mag. These gears are $800. AHH!. A call to Lycoming confirmed that if you dont have a right mag, then you dont need this gear. WHEW!.
The rat a tat tat in the motor at idle was the idler gear with the missing tooth. With no load on it, ie no mag, it had the opportunity to make noise.
So we accounted for all bearing parts, broken tooth, magnafluxed a few things, checked this and that, and put her back together.
So how the heck did a mag bearing get loose in my case? Pretty simple. The guy who installed his electronic ignition(ME) did NOT read, understand, and follow the instructions. From the LSE manual....
====
** Note- Magneto removal-
If you are removing a magneto that has a pilot bearing on the engine side of the magneto, be sure to remove the entire bearing with the magneto.
====
Seems this was an important piece of information.
Here is a picture.
MagBearingBusted.jpg
 
Hey mike

Lots of nasty looking stuff there.......

What can be said were like kids at Christmas sometimes and just skim the
directions,and can not wait to get the new toy installed.

Buddy, you know I am thankful that the destructions stayed in place, mostly, and that this did not self destruct the engine.


Smilin Jack
Cumming, Ga
 
** Note- Magneto removal-
If you are removing a magneto that has a pilot bearing on the engine side of the magneto, be sure to remove the entire bearing with the magneto.


Which magnetos would fall into this category?
 
** Note- Magneto removal-
If you are removing a magneto that has a pilot bearing on the engine side of the magneto, be sure to remove the entire bearing with the magneto.


Which magnetos would fall into this category?

My question exactly. I'm getting ready to install a second LSE. I'll be removing my left mag. The right one was never installed.
 
According to the parts catalogs, the 67542 bearing is on all 540's A,B,C,D,E and G series engines. I was not able to find any on the 360 series engines.
 
Me too!

First thing I did when I started my engine swap was pull the mags off and install the cover plate on one side and the pickup on the other. Do I need to yank them off and take a look???
 
According to the parts catalogs, the 67542 bearing is on all 540's A,B,C,D,E and G series engines. I was not able to find any on the 360 series engines.

Thanks... that makes sense. I forgot you were talking about a 6 cylinder Lycoming.
 
Kahuna I have personally seen these bearing failures damage three engines. If the balls get knocked around by the crank the case will look like it got hit with a shotgun. They're only $21 apiece and I think should be replaced at the 500hr check or sooner. Thats if they're being used with a mag install. The thing you have to worry about now is when the bearing seized, how bad did it damage the bore in the case. Might warrant a weld/machining repair on the case. Usually they can fill the bore with weld and re-drill the big hole. edit: duh you're no longer using that hole.

There are some 360 engines that use the mag support bearing. Whatever is in the Cherokee 180, I think its the A4M.
 
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Kahuna I have personally seen these bearing failures damage three engines. If the balls get knocked around by the crank the case will look like it got hit with a shotgun. They're only $21 apiece and I think should be replaced at the 500hr check or sooner. Thats if they're being used with a mag install. The thing you have to worry about now is when the bearing seized, how bad did it damage the bore in the case. Might warrant a weld/machining repair on the case. Usually they can fill the bore with weld and re-drill the big hole. edit: duh you're no longer using that hole.

There are some 360 engines that use the mag support bearing. Whatever is in the Cherokee 180, I think its the A4M.

The 360 A4M does not show the bearing.
Mine didnt seize. It fell out of its bore in the case. I failed to remove it when I removed the left mag a couple hundred hours ago when I went dual EI. When I removed the right mag on initial assembly for my single EI, I removed the bearing. Its pressed in, or at least a very tight fit. Mine required a bearing removal too to remove the first one. It should not fall out but it certainly can if there is no mag to retain it in there. I put the original one in a plastic bag and kept it(as seen in the photo). I have installed many 4 banger LSE EI's and never had a bearing to remove. Its why I failed to remove this one. Seen too many w/o them and I forget to check.
Case is fine. no sign of anything getting banged up.
Good to know that there is a failure mode of them seizing and causing havoc.
 
I had one case where this bearing wore a groove in the bore and the outer remnant of the bearing could not be pulled out without further damage. Sent the case to Chuck Ney and he literally ground the whole thing down to nothing, and built up a new one at the same spot with a couple of hours of welding. Like building an ant hill with tig rod, one dab at a time. This was after align boring since on these engines when the align bore occurs these two mag bearing supports are drawn closer together. Too close and the gears won't mesh properly in the accy case. Then the bore was redrilled and the outside shaped with a die grinder. Good as new after that.
 
Apologies to Mel Brooks

Instructions? We don't need no stinkin' instructions! [Parphrased from BLAZING SADDLES "Badges? We don't need no stinkin' badges!] Mechanics have a saying:
"When all else fails, read the instructions!"
Been there, done that, got the Tee shirt. :eek: Sorry to hear about your bad luck Mike. Thanks for giving us the benefit of your bad luck. Greatly appreciated.
Charlie
 
Badges, we don't need no stinking badges

OK nnot to be nit picky, but this is one of my favorite quotes.. ask my kids. anyways quote was originally from "The Treasure of the Sierra Madre" Mel Brooks stole it for Blazing Saddles.
 
Sorry to hear about your bad luck Mike. Thanks for giving us the benefit of your bad luck. Greatly appreciated.
Charlie

Charlie. Bad Luck? Man I feel lucky as all get out.
Sure it cost me some time. But I learned a lot, got to share some good times with friends messing with engines, lightened up my plane a little(took out the gear and tach drive), and have a new story to tell. I can live with that. Life is good. Learning plane stuff makes it all worth while.
 
I'm resurrecting this thread. My RV-8 turned into an RV-10 somehow and it's fixing to get dual lightspeed ignitions instead of the existing Bendix mags. Hoping Kahuna can re-post the photos. I'm also hoping for tips for removing the bearings and wondering how easy they are to drop into the case.

Guy
 
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