Flywheel rubbing ignition coil

Destroyer

Destroyer

God
Ok... I've got a problem. My engine (1991 Johnson 200hp Looper) wasn't dropping back to idle properly so I decided to pull the flywheel and look inside the stator to see if there was any tar gumming it up. First thing I noticed was that 2 of the magnets on the flywheel were out of position. They were loose. Next thing I noticed was that the inside bottom of the flywheel had some grooves worn into it. So I looked at the stator and saw that the coil in the front of the engine (the one associated with the magnito-ignition...one of the spark ignition coils) had wear marks on it that matched the groves in the flywheel. Either it's high or the flywheel is low. Both sit properly with no junk or crud under them... none of the other coils have any scuff marks on them, so that tells me that the one coil is high. How is that possible? Anyone got any ideas?

(I thought about pics as I was writing this, but it's dark and all my tools are put away for the night. I'll take some tomorrow and post them so you can see what I'm talking about)
 
when the magnets break loose like that, it throws the flywheel out of balance, I've seen it bend the crank snout, causing damage like you've found. Put a dial indicator on the crank snout an check it for run out.
 
spareparts said:
when the magnets break loose like that, it throws the flywheel out of balance, I've seen it bend the crank snout, causing damage like you've found. Put a dial indicator on the crank snout an check it for run out.
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Makes sense... I'll throw an indicator on it tonight when I get home from work. Can I epoxy the 2 magnets back into their proper position on the flywheel? They are ok, no damage to them, and they hold with great force on the flywheel anyways from the magnitizm, so thinking they should be ok. How do I disolve/remove the tar on the stator and whatever it is inside the stator. (The thing that is supposed to move to advance or retard the spark as the engine changes speed)
 
break clean will dissolve a lot of that stuff, just epoxy teh magnets back in plae, if you have to use a spacer, cut some out of wood to keep the magnets in their proper place
 
spareparts said:
see if you can move the crank side to side, it can damage an upper crank bearing as well
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Crank was solid.. tried moving it last night. I did notice that the groove for the keyway in the crankshaft looked very shallow. (meaning that the key looked like it was thinner than the keyway in the flyway). Is that usual? I'll take some depth readings tonight of the keyways.
 
spareparts said:
it aint much of a key way
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No, and the keyway is pretty soft as well. Make ABSOLUTELY certain that the crank and flywheel are as clean as possible before you torque the flywheel down or else it will shear the keyway off first time you get on plane(don't ask how I know).
 
THEFERMANATOR said:
No, and the keyway is pretty soft as well. Make ABSOLUTELY certain that the crank and flywheel are as clean as possible before you torque the flywheel down or else it will shear the keyway off first time you get on plane(don't ask how I know).
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Good to know..thanks for the info. It looked a little thin to me.. I'm used to seeing industrial keyways with half the key in each slot.. This one didn't look right at all.
 
Ok...got to thinking... the score marks on the inside of the flywheel are even all the way around... no mark is deeper than any other mark...and the groove is the same depth all around. If the crankshaft snout was bent so there was runout then one side of the marks on the flywheel would be deeper than the opposite side from hi-low flutter. That's not the case here. So then I put an indicator on the snout, put the engine in gear and using the prop turned the engine a few revolutions. No detectable runout on the stub.

Only one of the coils has rub marks on it. The spark coil closest to the boat hull. (There are 3 spark coils, 1 in the front of the engine and 2 that are 180 degrees from the first one at the back of the engine). Is it possible that the front coil is somehow high?? Is that even possible? :head:

Although the groove and marks in the flywheel appear to be bright metal, it's possible that this damage is old. Upon inspecting the flywheel I can see that a few of the magnets have been re-glued, so there was obviously a problem some time in the past. Only thing I can think of to do next is put Dykem on the top of the coil, remount the flywheel and spin the engine a few times, then take the flywheel back off and see if the Dykem was rubbed off. If it was then I know that it's hitting. If it's not then maybe this is all from the PO and it's a non issue. I'm totally stumped on this one. Aside from the gumming issue the engine runs strong. I just want to keep it that way.
 
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This are a few pics of the coils and the inside of the flywheel. They're not the greatest, but you can see the rub marks across the top face of the coil, and the matching rub marks in the flywheel. Since the pic is 2D and not 3D you can't really see the groove in the flywheel, but the outside wear mark closest to the magnets is not proud, it's actually a deeper groove, caused by the metal frontplate of the spark coil. Didn't have time last night to do the Dykem thing, so will be doing that tonight or first thing in the morning tomorrow. If nothing else, the stator will be getting a thorough cleaning before being put back into service. :cen:

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Um, where are your stator bolts at? there should be 4 5/16" headed bolts that hold teh stator down to the upper bearing carrier. I see the bolt holes, but no bolts in them.
 
THEFERMANATOR said:
Um, where are your stator bolts at? there should be 4 5/16" headed bolts that hold teh stator down to the upper bearing carrier. I see the bolt holes, but no bolts in them.
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LOL Correct... (Good eye Ferm) :) I should have included an explaination. I have them, they were where they were supposed to be. I took them out so I could lift up the stator to see if any junk was under it keeping the stator from sitting down properly and making it higher so the coil would hit the flywheel. Just didn't put them back in yet since I'm still doing a cleaning of some of the black tar that dripped down from the coils.
 
Looks to me like your SLOW coil is shot. That front coil with the black tar leaking out of it is for the SLOW system(rev limiter when the overheat trips it and such as well as the fast idle on start-up. I would gamble to say that it is seperating from the metal support ring at the bottom jusging from the rub marks in your picture. You see a small gap in your pics that would point to this. Looks like you may be due for a new stator.
 
Well, I pushed the coil down manually, then measured it in relation to the other 2 coils that were not rubbing. (It's about .007" lower) Then used epoxy, put it behind the coil and clamped it back in place until the epoxy set up. Waited a day and then started the engine. Everything seems to run ok and the engine now drops back to idle smoothly since the tar has been removed from around that area. But truthfully it worried me a little, so I ordered this
http://www.ebay.com/itm/200776406723?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
from eBay. They had it on a 12 hour sale, so I actually got it for $79 + shipping. According to the UPS shipping tracker I should have it by this Friday, so I can put in in over the weekend and keep the repaired one as a backup.
 
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