Sears/McCulloch 7.5 hp outboard replacement of coils riveted not screwed

[DickS]

I just got a 1966 Ted Williams/McCulloch 7.5 hp outboard on Craigslist Atlanta.  No spark so Coils checked dead.  Then I saw riveted laminates not screwed like Johnson, Mercury, Evanrude.  How have you dealt with this condition.  The motor is nice except for the cowl that will require fiberglass major restoration.  I have been able to find most of the parts by searching for Ted Williams, McCulloch, and Elgin 1960’s 7.5 HP on EBAY.  If you can help this newbe would appreciate the info.  Can I use coils for a Johnson or Evanrude?

[crosbyman]

how did you determine coils were dead….did you  do ohms  testing on primary and HV wires ..did you check the boot clip  connections

clean the points   check condensers for shorts or wide opens …or replace them

etc…

did you check compression before deciding to invest $$$$   post results !

easy stuff first  !!

 

Joining AOMCI has priviledges 🙂

[seakaye12]

It’s a bit unusual for both coils to be bad.  Possible of course.  You should thoroughly check other possible causes for no spark;  condensors, dirty points, bad wire to plug etc.

The coils themselves can be removed from the laminates.  The laminates are riveted on your particular motor but you can still swap the coils themselves.

LOTS of part motors around;  you should be able to find replacement ignition parts.

Can you post a picture of your mag plate?

[seakaye12]

Websites like this will help you determine which other outboards/mowers/etc share the same ignition components.

https://standardmagneto.com/Marine/outboard.html

From what I can tell….your coil is a 5-5074.  But I can’t be sure whether your magneto is a WICO or a Phelon.  Search through the pages and you will see numerous other applications for the same coil.  Armed with that you can look for parts motors.

Look over the mag plate carefully for a model number/Manufacturer ID.  If you post a picture we can probably tell you from that as well.

 

[DickS]

Crosbyman,

Right on point…I cut off boot and checked new cut wire to coil and got 6K ohms on each coil.  I can’t check for spark right now as I have everything disassembled to access carb for new kit.  The engineering on this McCulloch motor is unconventional but uncomplicated yet quirky.  I had already cleaned the points and the condensors seem to function buy my analog meter is not working so I get dc volts on my digital meter.  You have to remove the power head to remove the carb…not ideal as the carb needs more maintenance.

Thanks to all who answered…nice to not be walking this path alone!

DickS from Buford, GA

p.s. compression 70 psi top, 68 psi bottom.

 

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