1977 4.5 Merc - No spark

accord_guy

Seaman
Joined
Aug 31, 2004
Messages
68
I have a 1977 4.5 merc (1-cyl) that has no spark <br />at the plug. I do have spark at the leads coming from under the flywheel. I replaced the coil, but still no spark at the plug. I'm thinking of replacing the condenser, but at $70, I thought I'd look to outside help. My question is, would I still have spark coming from the stator (under flywheel), even if the condenser was bad? Like I'm not getting a strong enough voltage to fire the coil. Any advice would be greatly appreciated.
 

kelwendee

Seaman Apprentice
Joined
Jul 29, 2004
Messages
38
Re: 1977 4.5 Merc - No spark

can you check the wire for resistence? you said no spark at plug, do you mean at spark plug or wire plug? could be bad plug? condensers on a car i have experinced two diffrent problems when they have gone out, once they went out slowley like work sometimes then not, and the second failed all at once.<br />did you have your old coil checked to confirm it was shot? not sure if autoparts house can check a marine outboard coil or not but worth a check. <br />sorry not much help.
 

camo521

Recruit
Joined
Sep 2, 2004
Messages
5
Re: 1977 4.5 Merc - No spark

Hi, did you ever find out whats wrong with the 4.5hp motor? I have a 1972 4hp that has the same problem. thanks Bob my e-mail is bobd@rochester.rr.com
 

camo521

Recruit
Joined
Sep 2, 2004
Messages
5
Re: 1977 4.5 Merc - No spark

Hi, did you ever find out whats wrong with the 4.5hp motor? I have a 1972 4hp that has the same problem. thanks Bob my e-mail is bobd@rochester.rr.com
 

accord_guy

Seaman
Joined
Aug 31, 2004
Messages
68
Re: 1977 4.5 Merc - No spark

I'm in the process of replacing all the wiring<br /> Finally have spark to the plug after <br /> discovering the kill switch was grounding to<br /> the cowl. Now that I have spark, fuel system <br /> is next. If your coil is outside the flywheel, <br /> check the small ground wire underneath. <br /> Good luck. These are great motors to restore. <br /> The hard part is paying thru the nose for <br /> parts.
 
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