How to change coils, set points on Old OMC's-with pics

[coolguy147]

Re: How to change coils, set points on Old OMC's-with pics

lol i remember this post it really helped me a lot

 

[turtles11756]

Re: How to change coils, set points on Old OMC's-with pics

thanks for posting. big help starting with flat side (harmonic balancer) up. setting the points in my 74' corvette was easy compared to this but that's been awhile too

 

[diann1]

Re: How to change coils, set points on Old OMC's-with pics

Were is the throttle to be set when setting the points
Thaks for you help

 

[rjezuit]

Re: How to change coils, set points on Old OMC's-with pics

Does not matter, rotate until one set is fully open and gauge .020" rotate until the other set is fully open and gauge .020".

 

[tallcar]

Re: How to change coils, set points on Old OMC's-with pics

Also note that there is a dimension that the coils need to be, that can be set with a simple tool called a ring gage, or possibly a dial caliper. OMC used to make them but not sure if they do now, as a plug for iboats, I do not know if they or any other business makes them but I do know of an individual that does make such a ring. Very inexpensive, but generally you can feel a ridge around the underside of where the coil heel sits. This is a machined area for a purpose, it is where the coil heel should be, not out past this point. One trick is to use a small six inch scale to ensure the heel does not protrude past that point. I have and still do repair many older outboards, and this is what is called a universal magneto, I believe is is used on motors ranging from 3-40 hp, from the mid 50's thru the 70's. These coils can be found for around $14, but unfortunately not on iboats for that price

If you wish I can get you the actual OMC part number for this setting ring, and or the actual decimal dimension that the coils should be, as their spacing in reference to the flywheel as it passes determines the quality of the spark, too far away weak spark, too close and it will hit the flywheel causing serious damage.

I am a member of the AOMCI, cuz we love the older outboards.

Richard White
1914 Evinrude 2 hp Rowboat motor, oldest toy
40 different motors between here
1974 55 Evinrude 25hp Bigtwin Electric newest toy

 

[ezeke]

Re: How to change coils, set points on Old OMC's-with pics

Also note that there is a dimension that the coils need to be, that can be set with a simple tool called a ring gage, or possibly a dial caliper. OMC used to make them but not sure if they do now, as a plug for iboats, I do not know if they or any other business makes them but I do know of an individual that does make such a ring. Very inexpensive, but generally you can feel a ridge around the underside of where the coil heel sits. This is a machined area for a purpose, it is where the coil heel should be, not out past this point. One trick is to use a small six inch scale to ensure the heel does not protrude past that point. I have and still do repair many older outboards, and this is what is called a universal magneto, I believe is is used on motors ranging from 3-40 hp, from the mid 50's thru the 70's. These coils can be found for around $14, but unfortunately not on iboats for that price

If you wish I can get you the actual OMC part number for this setting ring, and or the actual decimal dimension that the coils should be, as their spacing in reference to the flywheel as it passes determines the quality of the spark, too far away weak spark, too close and it will hit the flywheel causing serious damage.

..........

Iboats sells a CDI coil locating ring: http://www.iboats.com/Johnson-Evinr...4296561--**********.028004085--view_id.336097

The OE part was 317001, now superseded by 0334994.

 

[phineas]

Re: How to change coils, set points on Old OMC's-with pics

great info , read it a million times, over the last couple years, it ll it easy thanks to tips on here and doing it a few times, thanks to all the fellows who know

 

[hdman97]

Re: How to change coils, set points on Old OMC's-with pics

Hi Guys,
Great info here,can anyone tell me where new coils can be found?
and what is the proper Torque for the johnson 5 1/2hp 1955?
Thanks......

 

[1946Zephyr]

Re: How to change coils, set points on Old OMC's-with pics

Hi Guys,
Great info here,can anyone tell me where new coils can be found?
and what is the proper Torque for the johnson 5 1/2hp 1955?
Thanks......

Any marine dealor sells the coils for your motor. If you don't have a dealor close by, try Napa.

 

[F_R]

Re: How to change coils, set points on Old OMC's-with pics

Aside from obvious cracked coils, the most common problem you will find are dirty or worn points. They simply cannot be worn out or greasy and expected to work right. The points are the ground circuit for the coil primary and must make a perfect "connection" to ground as the magnets start past the coil laminations. There is zero voltage to begin with, quickly rising to around 6 volts. Not a whole lot of voltage to break through a bunch of resistance from grease & corrosion.

Already mentioned, but worthy of repeat is the proper reinstallation of the flywheel. The tapers MUST be clean and dry, and you MUST use a torque wrench to tighten the nut to specs. Failure to heed will result in a sheared key at the least, and very often destruction of the flywheel and/or crankshaft. When that happens you might as well put it out at the curb for the trash pickup.

 

[ezeke]

Re: How to change coils, set points on Old OMC's-with pics

Hi Guys,
Great info here,can anyone tell me where new coils can be found?
and what is the proper Torque for the johnson 5 1/2hp 1955?
Thanks......

5.5 Flywheel nut torque = 40 to 45 Foot Pounds (480 to 540 Inch Pounds).

 

[F_R]

Re: How to change coils, set points on Old OMC's-with pics

Support out host. Coils, points & condensers can all be found right here at iboats.

 

[hdman97]

Re: How to change coils, set points on Old OMC's-with pics

Many thanks guys!

 

[phoodieman]

Re: How to change coils, set points on Old OMC's-with pics

1967 RSDL 40HP Johnson Super Sea Horse

I've been trying to get at the points to inspect them, but my fly wheel is stuck. I broke a couple of regular 1/4 20 bolts on the puller and now I will move on to some grade 8's , but my concern is that the fly wheel is on so tight that I will pull the aluminum mating holes out when the grade 8's don't give up. Can I soak the taper to loosen it up?

Phoodieman

 

[asdasc]

Re: How to change coils, set points on Old OMC's-with pics

I have always used the grade 8's and never had an issue. They are on very tight, and should be. I wouldn't worry about ruining the threaded holes, they can take a lot if they are in good condition. I haven't ever needed any solvent either. Just use the good bolts, tighten up the puller and let it set overnight. Give it another 1/4 or 1/2 turn every day, and it will probably let loose with a loud bang in the middle of the night. Good luck and let us know how it turns out.

 

[samo_ott]

Re: How to change coils, set points on Old OMC's-with pics

There is a small steel plate inside the flywheel where the threaded holes are which make it pretty strong. Don't ask me how I know....

 

[1oldmaster]

Re: How to change coils, set points on Old OMC's-with pics

Am I correct in assuming the flywheel torque spec for a 1973 Johnson 6 hp would also be 40 to 45 foot pounds? Also what gear lube is recommended for the lower unit? Any idea on the quantity? 1 quart or less?

 

[nwcove]

Re: How to change coils, set points on Old OMC's-with pics

cant comment on torque specs, but marine grade 80w90 should be ok for the gear case (i use automotive 80w90, but others dont like using it). as far as quantity goes, mount your motor upright, as it would be on the transom, remove both the drain and fill plug (get new nylon washers ) and fill from the bottom untill it comes out the top hole. a quart should give you two fills,one,after a day of running, and another fill to see your gearcase is leaking.

 

[jamesh1120]

Re: How to change coils, set points on Old OMC's-with pics

did you diagnose your issue? I have the same motor and same problem. I have a 1964 9.5 Johnson. I am not getting a spark on the top plug. Please let me know what you did to correct.

 

[crackburglar]

Re: How to change coils, set points on Old OMC's-with pics

I know this thread has been idle for a long time, but I have an observation to make about some points that I recently set. Relay to readers that when setting the .020 point gap, make sure that the opposite set of points is CLOSED.

The motor I was working on would only fire on 1 cylinder, no matter how many times I set the gap, OHM Meter tested all the particular coils, condensers, and checked good connection and continuity on the high tension spark plug wire and end pins, the motor just would not fire on both cylinders.

THEN after pulling the flywheel for the umpteenth time, I set the one gap, and just happened to notice the other gap was also open. A few minor adjustments, and re-checked gaps, Engine fired on both and now runs strong.

I had followed the guide down to precise detail, and until I made the discovery by accident, I kept getting the same result.

I'm not sure if this tip will help anyone, but it definitely would not hurt. Happy boating!