ignition problems Merc 50 - 3 cyl.

[upwindskipper]

I have a 2002 50hp - ELO. Light use, summer only. Starting was intermittant this spring, once started, she ran beautifully.

I replaced the ignition switch with no difference in symptoms. Today I replaced the solenoid and she has refused to crank at all. I can jump the solenoid and spin the starter.

The 20 amp fuse is OK. Is there any other part between the battery and starter that i need to inspect? Thanks in advance for any advice.

 

[Faztbullet]

Re: ignition problems Merc 50 - 3 cyl.

Neutral safety switch...............

 

[upwindskipper]

Re: ignition problems Merc 50 - 3 cyl.

Thanks Fatzbullet: Is there a separate "switch" inside the Merc controls ? (I am operating without a manual...)

 

[achris]

Re: ignition problems Merc 50 - 3 cyl.

Neutral safety switch is inside the control box, yes. Download a service manual HERE

Chris..

 

[upwindskipper]

Re: ignition problems Merc 50 - 3 cyl.

Thanks Chris. That's the only place I have not looked for the problem.

 

[upwindskipper]

Re: ignition problems Merc 50 - 3 cyl.

No luck with the neutral safety switch, I opened the control / shift module and it looked just fine. Taking no chances, I disconnected it entirely so now yellow/red runs from the (new) ignition to the (new) solenoid.

With the motor tilted up, I get a dry alarm with the key switch on. I also get a barely audible choke "click" with the key pushed it - but no cranking with the key over. I can jump the solenoid and get the starter to engage so I expect the starter is fine.

Weekend fast approaching - family wants to go boating. any help appreciated.

 

[achris]

Re: ignition problems Merc 50 - 3 cyl.

You're now going to have to diagnose it the old way, with a meter. Put the meter red lead on the small solenoid terminal with the yellow/red wire on it and the black lead to the block lead on the solenoid, now get someone to turn the key to START. You should get 12volts. If you don't, then move the black lead to the engine block and check again (looking for a bad ground). If you now get 12 volts, then the ground wire to the solenoid is bad. If you don't have 12 volts, then you need to check at that junction where the safety switch was (that you removed from the circuit). If you get it there, then you need to be looking for a break in the wire between the control box and the solenoid.

Chris..........