Intermittent start on 21EC

[bjp447]

We have run this question around the Technical chat and I could use some factory advice.
On a 2012 12Ec with a 30HP yanmar, when turning the key to start the engine may or may not turn over.
When I turn the key the engine may immediately start or nothing. I have metered to the start solenoid
and when I click the key to start I appear to get 12 v but nothing happens. I know the 12 v are there but I don't know
the amps. I can start the engine every time with a remote starter with one lead on the solenoid and the other
on a 12 v post on the battery, hit the trigger and I am running. I can't find a schematic that shows the path between the
start switch and the starter solenoid. In one of the posts someone mentioned a safety relay(no mention of it anywhere)
I found 3 relays that appear to relate to starting in the parts manual in figure 33 in the parts manual. I am thinking of ordering them, but again I don't know where they fit in the starting system. Figure 34 shows the switch but still no path.
Any thoughts?
Thanks
Bruce
Marietta GA

 

[Capt’nKarl]

Bruce, I've had the same issue more than once with my Yanmar and the solution may be simple. Before you go buy anything try this. Jiggle the throtttle handle a little. You may find,as I did, when the handle is in NEUTRAL there is a sweet spot where the engine will crank OR it is in that little spot (wrong) position to keep the engine from starting. Jiggle it a little.
Cheers,
Karl

 

[Brian B]

If the neutral safety switch is similar to the Yanmar 150 or 180 HP this thread may help.
viewtopic.php?f=5&t=7329&p=51968&hilit=Neutral+safety+switch#p51968

 

[bjp447]

One point I forgot to add
When you put the key in the on position before moving to start there are 2 lights
that should lite. I don't recall if it is battery & temp or oil & Temp. The left lite does not light
and the right lite appears dim, Batteries are good. And the alarm does not go on. This happens
when the boat will start. When the 2 lights do come on and the alarm goes off the engine does not start
(I think). I will try the switch jiggle. Thanks

 

[bjp447]

Finally just threw money at the problem, new starter fixed it.
It would start with a remote starter hooked between the Solenoid
and the Positive battery post, but not with the key. Who knows why!
I am just glad it now works