Problem with 1974 Mercury 402

[hotpickle]

Hey guys, I got a 1974 mercury 402 (40 hp) with electric start and controls. When I bought it last summer, it ran no problem. When I tried to start it this year, all that happened was a *click* (pinion gear). The flywheel doesnt crank, nothing happens. Things I’ve tried:

-replacing (some, not all) old wires
-testing battery
-new starter solenoid
-jumped negative terminals on neutral safety
-tried to jump starter solenoid

I tested it in a few places with a multimeter, following the test procedure in the Clyne’s manual…. Nothing out of the ordinary. I dont know whats going on. Anyone got any ideas?

[hotpickle]

I’ve also spun the flywheel and moved the throttle, it moves in and out of gear, and sits in neutral no problem

[retiredoz]

Try jumping the negative battery terminal to the block. If you’re REALLY lucky, your problem may be a bad ground..

[billw]

I’m not a fast typist; so I will just go one or two steps at a time.

Remember the golden rule (in my feeble mind) for electricity: In order for it to accomplish anything, it has to be able to get there, and to get back. Think about it. If you use a volt meter (the old analog type is better for starter things, I think; but digital is fine.) and you see you have 12 volts going into a wire and only 7 coming out, then the problem lies between those two points. This is just a generalization for what is to follow.

Also, starter circuits can’t be tested with an ohm meter or even a volt meter, if not under load. So you will either need an assistant at the key switch or clips to hold your meter wires at various test points.

So. Take your volt meter and connect it across the battery terminals. Try to crank the engine. If you have 9.5 volt or more at the battery, (Preferably more) your battery is probably okay. Move your meter leads to the negative and positive posts on the engine. Try to crank it again. Again, you’re looking for 9.5 or higher. If you have that, then go from the negative engine terminal to the starter input terminal. Crank again. Still got 9.5 or higher? That would mean your system has the capability to get electricity to the starter and back and you have a starter problem. If you fail any of these tests, you have a problem BEFORE the starter. Either the electricity can’t get there, or it can’t get back. Now you go back and find where, in between these points, you’re loosing it, by moving first your positive, then if need be, your negative meter lead, from point to point along the circuit. There is, of course, potentially more to it than this; but let’s start simple. Report back.

Long live American manufacturing!

[donsmarine]

take starter out,put on hard surface,hold it down well,connect it directly to battery with jumper cables,+ positive clamped on,-negative touching quickly,on starter not battery,it should spin,good place to start.known as bench testing.

[Author]

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