25 mercury electric starter issue

[goblerblaster]

My 1987 25 Mercury will start and run fine using the rope pull. When I use the electric start button, I can hear the solenoid click and the starter gear will engage the flywheel but most times will not turn the flywheel. I have replaced the solenoid and starter but same problem exists. The battery is fully charged and holds a charge. Sometimes when I hit the button the gear on the starter does not engage -or even move, but the solenoid clicks. In messing with it, I have noticed that the flywheel stops in the same location in its revolution- nearly every time. I can move the flywheel manually an inch forward or backwards and then -when I hit the starter button- the starter will engage and turn the motor over like it is supposed to.

I have swapped the battery from my other boat-that has a 115 Evinrude- and when I put that battery on the 25 Merc- same issue continues. Again, no internal engine problems that I can determine, since it runs, idles, accelerates, great when started with the rope.

Any suggestions will be most appreciated.

 

[achris]

Re: 25 mercury electric starter issue

Is the starter grounded to the engine block with the right cable? Is the battery negative cable secured to the engine block clean and tight?

 

[goblerblaster]

Re: 25 mercury electric starter issue

Is the starter grounded to the engine block with the right cable? Is the battery negative cable secured to the engine block clean and tight?

There is no negatigve ( ground) wire from the starter to the engine block. The starter bolts tight to the block itself, so I assume that is a good ground. There is only a yellow wire running from the solenoid to the starter. The hot wire from the battery to the solenoid and the black wire from the baqttery to the engine block ground have new ring connectors and are tight to the block. Thanks.

Any other suggestions?

 

[VAfan]

Re: 25 mercury electric starter issue

Sounds like the same low voltage issue I just had on my 99 - 25hp.

After replacing/cleaning connections and the solenoid the main problem was the battery cables. Not sure which one or both…..replacing both cables solved the problem. A local boat shop told me it’s a common problem on older boats. On mine….the ground wire from the battery goes on the starter right mounting bolt.

 

[MH Hawker]

Re: 25 mercury electric starter issue

Before you do any thing else take apart ever connection no mater how good it looks and clean and polish each one. That will cure 70 % of starter problems.

 

[goblerblaster]

Re: 25 mercury electric starter issue

Before you do any thing else take apart ever connection no mater how good it looks and clean and polish each one. That will cure 70 % of starter problems.

OK, I have replaced both battery cables and the wire running from the solenoid to the starter. I have checked to make sure I have a good ground from the battery to the engine block using the right side bolt that holds on the starter. I get 12 volts from engine block to positive battery cable connection at the input side of the solenoid. I get 12 volts from ground to the output side of the solenoid when the start button is pushed. The battery is fully charged. I ran new wires from the starter button to the rectifier and solenoid. Same problem still exists. Sometimes the starter will turn over the engine fine, sometimes the solenoid "clicks" but bendix does not move up, sometimes bendix moves up but will not turn the engine. If the bendix does not spin up, I can spin it by hand backwards and it will almost always engage the flywheel the next time I hit the starter button- but may not turn over the engine. If the bendix engages the flywheel but won't turn it- I
I can turn the flywheel by hand a little and then the starter will turn the engine over.

ANy other ideas? Are the aftermarket starters on ebay worth anything, coz I have tried two of them and am beginning to wonder if they are just crap. Both have tested good and spin when not hooked to the motor. Who makes "factory" starters for the 1987 25 HP Merc? Thanks.

 

[achris]

Re: 25 mercury electric starter issue

Almost sounds like the starter lacks torque, or is 'polling' on start-up... But you've tried 2 different starters.. ??? How is the alignment of the starter? If you turn it by hand and 'feel' the bendix into the starter gear, a good engagement?

Chris.....

 

[goblerblaster]

Re: 25 mercury electric starter issue

Almost sounds like the starter lacks torque, or is 'polling' on start-up... But you've tried 2 different starters.. ??? How is the alignment of the starter? If you turn it by hand and 'feel' the bendix into the starter gear, a good engagement?

Chris.....

Bendix gear engagement is fine- when it engages. Liewk I said above, sometimes it works perfect, sometimes the solenoid clicks and bendix doesn't move. Its almost like it doesn't have enough power to turn the flywheel when it engages and I hold the starter button - it will do nothing but knid of whine for a couple of seconds, then may suddenly start turning over. I have noticed that the flywheel stops in almost the same place every time I stop the engine. I can manually turn the fly whell from this "normal" stop location and it will turn over when the button is pushed- most times.