1976 65hp merc NO SPARK

[catmotorhead]

I have a 1976 65 hp merc i ran it in the lake and the impeller was bad so i pulled it out and put a new impeller on it. I started it in the drive way it pumped water and ran great i drove it 10 miles to the lake and it hasn't had spark since. Ive have to much invested into it to scrap it out. I think i can fix it my self. Ive checked most everything im down to the switch box or cdi or the stator. a mechanic said he was getting spark on 2 plugs then it stopped. i didn't trust him so i got my boat back. I JUST WANT TO GO FISHING
Thanks
Charley

 

[Laddies]

Re: 1976 65hp merc NO SPARK

Disconnect the black/yellow wire from the switchbox and recheck for spark, here's the CDI system test

 

[catmotorhead]

Re: 1976 65hp merc NO SPARK

Thank you for responding this thing is killing me. I have a pretty good diagram of the electrical system and it seems i do not have an orange wire and the reason is, according to this diagram i have the later model that is equipped with a distributor. The other diagram has an orange wire it goes up to the mercury switch. I have tested my mercury switch and it seems to be functioning properly.

 

[Laddies]

Re: 1976 65hp merc NO SPARK

With a dist the engine is not a 76 that's why you can't find the right info, right info in = right info out.

 

[Laddies]

Re: 1976 65hp merc NO SPARK

With a dist the engine is not a 76 that's why you can't find the right info, right info in = right info out.

 

[oldman570]

Re: 1976 65hp merc NO SPARK

Check the kill switch on the throtal control to make sure it has not gotten triped at some point in time. also check all the fuses on the motor.

 

[catmotorhead]

Re: 1976 65hp merc NO SPARK

well it may not be a 76 the manual i have is for a 72-76. i checked the key switch for continuity and it seems to be working properly. and now heading out to the garage to use the troubleshooting info above.
thanks
charley

 

[catmotorhead]

Re: 1976 65hp merc NO SPARK

Is there a way to check the stator and a way to check the switch box?

 

[Laddies]

Re: 1976 65hp merc NO SPARK

The stator is not part of the ign system on that engine but if you ring test it end to end and have continuity it's OK. It's very simple yo test the ign system if you would read the test you have already been sent in post #5. If you don't want or need help just say so and I will quit wasteing our time.

 

[catmotorhead]

Re: 1976 65hp merc NO SPARK

You know its a lot easier said then done i appreciate and want the help. i bought a spark gap tester. I attempted the no spark on any cylinder test and was unable to get spark however when i jumpered the wires and aligned the rotar to the plug wire i got the spark only on the plug i was trying for like it said. It worked on all three plug wires. i dont know what that means but i was super happy to see that bright blue spark no matter how fast it came and went.

 

[Laddies]

Re: 1976 65hp merc NO SPARK

If you have fire jumping the system with the key on and the drive belt is not broken then the trigger is bad.

 

[catmotorhead]

Re: 1976 65hp merc NO SPARK

bad trigger. thank you very much i will replace this and post my outcome.any tips or tricks to this?

 

[catmotorhead]

Re: 1976 65hp merc NO SPARK

Do i have to replace the whole assembly or can i just replace the part with the wires attached. I live in midland MI, Finding parts is going to be a challenge unless i want to pay $465

 

[Laddies]

Re: 1976 65hp merc NO SPARK

Unfortunitly it's one piece the merc part # is 332-4797 and Rapair will rebuilt last I knew part # R332-4797 try to google the #