1973 Mercury 7.5 Hp starting problems...

Hello all, I had enough trouble with this motor last year that I decided to let you guys help me out right from the start. I have a 1973 Mercury 7.5 Hp Outboard motor. I would love to get it going because my 40 Hp Johnson guzzles the gas, and at $1.14 per litre here in Canada at the moment, I would still like to get out and fish.<br /> <br /> So where to begin...I tried starting the motor last summer and after pulling my arm off it started and ran beautifully. I let it run for like ten minutes and turned it off. I tried starting it again twenty minutes later and nothing. Pulled and pulled and pulled and nothing. After a really great local mercury dealer told me to replace the stator coils, I did. I pulled and pulled for a while more before deciding that the stator coils were not the problem. I removed the carbeuretor and cleaned it right out. Checked the points and they are in great shape. This motor ran beautifully the last time it was used and now I can't get it going. Does anyone have any insight as to what I should be trying to do? I tested the ignition module and it is great. I tested the capacitor and it is great. I checked the stator coils and they are great. Is there anything I could be missing? I check and found that the carbeuretor gets gas. Spraying into the carb does nothing for starting it. I am sure it is electrical. What should I try to get this beast moving.....LOL! Please help fishing season is here soon and I don't want to miss it again. Serial number 7009691. It is a Canadian model.

Re: 1973 Mercury 7.5 Hp starting problems...

So I went online to ebay.ca and purchased a new capacitor and a new ignition module. Hoping that will solve the problem, any other ideas I should try to get this motor running?

Re: 1973 Mercury 7.5 Hp starting problems...

I have a '73 merc 7.5 motor and had similar troubles starting. I took a look around and found that the ignition wires which are very old were cracked. So I taped them up and it worked for a while. Then I began to have problems with motor not starting when cold. So I pulled the flywheel and found the wire under the flywheel that goes to the points was corroded. I tried to match the type of wire and replaced it. I then filed the points which were bad and put it all together. Runs good in barrel but still won't start without putting fuel into carb. So now I have to try to replace all carb gaskets even though the carb is very clean. Hope this will help you and I'll keep working on mine.
Cornell thecruiseguy

Re: 1973 Mercury 7.5 Hp starting problems...

The insulator blocks on the point studs crack and the engine will still have spark but will start very hard. Have you changed them?

Re: 1973 Mercury 7.5 Hp starting problems...

Laddies said:

The insulator blocks on the point studs crack and the engine will still have spark but will start very hard. Have you changed them?

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Hi Laddies, thanks for your help in the past. I read your answer to Sascatuon??My 7.5 Merc will start but only when I squirt gas into carb or spark plugs. Do you think that would be my problem as answered above regarding bad insulator blocks on points. My carb is clean and gaskets appear very good by looks and impressions on seal. Runs good in barrel once primed.
Cornell email; thecruiseguy@comcast.net

Re: 1973 Mercury 7.5 Hp starting problems...

STOP throwing parts at it. Parts replacement is the most used, most expensive and least effective troubleshooting method known to man.

Go to the Engine FAQs Forum and do "Outboard won't start". That will tell you what system is not working. Then tell us what you found.

We can go from there.