M25 - Strange but Consistent "starting" behavior

Happy sailing season, all!

I have a strange but repeatable engine starting behavior that has me concerned (E-35, 1984, M25). First noticed this behavior mid-last season: when I would hit the start button I would get a very brief crank from the starter motor and an abrupt starter motor stop (this brief starter motor crank is very short, like < 1/4 second or less). After this abrupt starter motor stop, I release the start button, repress the start button and the everything will crank normal and start the engine just fine. My batteries were at end of life last season and I suspected failing batteries ... just changed them out for new a few weekends ago and have the same starting behavior.

This happens both first fresh start of the day and after hours of sailing and subsequent restarting returning to the marina. If, after a fresh start, I shut down the engine and then reseat right away, it will turn over normally without the abrupt pause.

Any thoughts on what could be causing this or other checks I can perform to find root cause? Do you think I have a problem (slowly failing starter motor)?

I have a 1983, 35.

Check the inline fuse that goes to starter celinod (did not spell it correct). If any rust on there.... could be the problem.
Mine on Sketcher did this in the past.

Hilco on Sketcher.

Starter solenoid. Sounds like the contacts might be dirty or burned.

And after checking the solenoid, consider rebuilding the starter motor.

The motor has been working 30 years without thanks and is often the cause of intermittent issues. It is especially likely to cause
questions about battery health when the engine turns over unenthusiastically. Diesels reward a vigorous spin by the starter motor.

Lots of us have done this. Just a matter of taking the motor off and dropping it by an alternator shop.

On my M25 the engine spun twice as fast after a $25 starter overhaul.

Start message #3 at http://www.ericsonyachts.org/infoex...drometer-plus-potential-starter-motor-isssues

EMKoper said:

Happy sailing season, all!

I have a strange but repeatable engine starting behavior that has me concerned (E-35, 1984, M25). First noticed this behavior mid-last season: when I would hit the start button I would get a very brief crank from the starter motor and an abrupt starter motor stop (this brief starter motor crank is very short, like < 1/4 second or less). After this abrupt starter motor stop, I release the start button, repress the start button and the everything will crank normal and start the engine just fine. My batteries were at end of life last season and I suspected failing batteries ... just changed them out for new a few weekends ago and have the same starting behavior.

This happens both first fresh start of the day and after hours of sailing and subsequent restarting returning to the marina. If, after a fresh start, I shut down the engine and then reseat right away, it will turn over normally without the abrupt pause.

Any thoughts on what could be causing this or other checks I can perform to find root cause? Do you think I have a problem (slowly failing starter motor)?

Click to expand...

I had a problem just like what you describe on my last boat. (The engine was an M25XP.) The starter and solenoid checked out OK. Though the electrical connections appeared good, it turned out that in fact the ground was not making good enough contact. (As I recall it, the ground relied on the bolts affixing the starter to the engine and the physical connection of the starter to the engine itself.) Make sure you have an excellent ground and see if that doesn't fix it. You could even add an additional ground cable to the starter just to make sure.

I'm having similar issues. Towards the end of last season, I would get a single click from the starter solenoid when I pressed the starter switch. After 4-5 attempts (each with a single click) the solenoid would eventually catch and crank the engine to start.

A few weeks ago, the solenoid quit catching altogether-just a single click with the start switch depressed.

Troubleshooting is in progress as follows:

1. Suspected the batteries, but problem persisted after a full charge, and all 3 battts selcted while still hooked to the charger.

2. Tried the Metzger "orange wire mod," connecting the heavier gauge orange wire to the starter solenoid's yellow-red lead.

3. Replaced the starter switch. The brass casing on the old switch was cracked in two places--probably had moisture damage.

Result: The clicking noise is gone completely, but about 2\3 of the time, I hear the starter motor spinning without engaging the gear. The other 1/3 of the time, it cranks smartly and fires right up.

Starter motor was rebuilt last season. New fuses in both the yellow-red solenoid wire and the engine-panel in-line fuse to the key-switch. Still wondering wether it's a solenoid issue or a high-resistance/low current issue in one of the wires or connections I haven't replaced yet.

Thanks Allan--I had been focusing on the supply lines, but not the grounds. Definitely worth a look...

Thanks all, great advice ... I'll do the checks and let everyone know how it goes.

I will be happy, Christian, if I can get the starter off without too much trouble -- I looked closely at it while I was changing the transmission fluid last weekend and was wondering if I'd have to do any "engine or personal gymnastics" to remove it (while I was stretching my body beyond my typical limits to change the transmission fluid).

As I recall the trick was an extension on a ratchet and dealing with tight quarters and awkward access. There are only two bolts, but it helps to know some human has successfuly done it before.