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OMC Timing fixtures

Jogin

New member
Hey everybody, I am new here and would like to say first off this looks like a great forum with a lot of knowledgeable techs on here and I hope I can offer my experiences and knowledge at some point also. The main reason I am posting today though is because I am looking for a set of Timing fixtures for setting OMC's Breaker points. I believe the part numbers on them are

383601
383602
383603
378966
386635
386636

I believe there were only six in total, but there may be one more. If anybody has these and is interested in selling them please let me know, or if you know where a guy could get them I would also appreciate it.

Thanks and I cannot wait to learn from you all and also hope you can learn some from me.
 
These are nothing but ---" dummy flywheels "-------------u can use the flywheel marks and the marks on the magplate !!--------------Visit the------------- AOMCI -----website I bellieve one contributor makes new ones.
 
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Yeh, and if you have a dial gauge with adapter for spark plug offset (Or take the head off) , a felt tip marking pen, a degree wheel and a battery powered inductive timing light, multimeter and some thought with all that.......... you can actually get things as you want. Running on the fuel available to you as well.

Just a note, always best to mark up and deal with your own flywheel as above.

Under Our Sun?

Nothing New

Regards

B
 
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Next time you run an older OMC , aim a timing light at the two vertical marks on the magplate.-----------You will then see the timing marks on the flywheel as well.----------These can also be used for setting the points correctly------------------------And I have been doing this since 1968-----You are busted !!!
 
I never really thought of using the timing marks on the flywheel and corresponding them with the timing marks on the mag plate. I guess the only issue I have with that is having to remove the flywheel each time to adjust the point set screw. This bothers me since Removing the flywheel I am sure it will turn the crank a bit. Thanks for the input and help, and I will check out AOMCI to see if they have them for a reasonable price.
 
If you lock the magplate some how and carefully remove the " loose " flywheel , then nothing goes out of position.------------I have the fixtures , have used them many times.--------Sometimes when I can't find them in a hurry I set the points the other way.--------------I never use feelers to set points !
 
(Point Setting Of Magneto Models)
(J. Reeves)

Set the points as follows. Have the flywheel key aligned with the fiber rubbing portion of the ignition points. Adjust the gap so that a .020 gauge will pass thru but a .022 will not. Should there be any question of the points being dirty (touching the contact with your finger would cause them to be dirty), clean them with a small brush and acetone or lacquer thinner.


NOTE: Should the operating cam have a small portion on it with the word "SET" imprinted, align this portion with the fiber rubbing portion instead of the flywheel key.
 
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(Point Setting Of Magneto Models)
(J. Reeves)

Set the points as follows. Have the flywheel key aligned with the fiber rubbing portion of the ignition points. Adjust the gap so that a .020 gauge will pass thru but a .022 will not. Should there be any question of the points being dirty (touching the contact with your finger would cause them to be dirty), clean them with a small brush and acetone or lacquer thinner.


NOTE: Should the operating cam have a small portion on it with the word "SET" imprinted, align this portion with the fiber rubbing portion instead of the flywheel key.

Thanks for this post. I purchased an OMC manual and the procedure shown in it required special tools and using marks and such. So I tried your procedure. It was easy and it seemed to fix the last of my problems (which was poor performance when accelerating from slow). The points were only off by a few thousandths but it made a difference.
 
I would think that using a timing fixture set part set to the midway point between the two timing marks on the armature plate then adjusting the points with a 20 thousands feeler gauge would be way more accurate than any light or eyeballing the lobe or the flywheel key on the drive shaft, then you are ensuring that the points open at exactly the right spacing perfectly opposite from each other.
 
?????--------------No , using those fixtures or the actual flywheel and a light or buzzer is more accurate than using feeler gauges !!!!
 
?????--------------No , using those fixtures or the actual flywheel and a light or buzzer is more accurate than using feeler gauges !!!!

I understand the fixtures and timing marks on the armature or flywheel, not getting how a light or buzzer can be more accurate than the feeler Guage at measuring 20 thousands gap between point contacts.
 
NOTE: This post is over four (4) years old..... Start a new post.

However,,, ignore the light and buzzer thing. The gauge at .020/.022 setup gets you within factory specifications.
 
The light or buzzer detects where the points open and that is the critical thing on a magneto.-------The actual gap is of no consequence.
 
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