[C38] Yanmar starting problem

[Les]

On Sat, 2007-07-14 at 22:14 +0000, eyriepg at comcast.net wrote:
> While few of you have Yanmar engines, my symptoms are probably not
> unique to this engine.  Sometimes when I press the engine start
> button, nothing happens.  Most of the time that this is an issue,
> there is no sound at all.  The second or third press of the button
> works every time.  I think..??....that I can hear the starter start to
> engage some of the time that it doesn't start.  This has been a
> problem off and on for about 2 years.  Last week when I was about 50
> miles from anything, the radar/chartplotter consistently dropped off
> when the engine failed to start.  Now that I'm contemplating a longer
> cruise I think that I should fix it.  Another fact is that it almost
> always starts first thing in the morning leaving the dock and it is
> more likely not to start after I have been out sailing for a couple of
> hours.  I had my batteries checked and they are excellent.
>  
> Any wisdom would be appreciated.
>  
> Phil Gay
> C38 049 Que Linda
> Everett, WA
Hi, Phil,
	Since you say the chartplotter consistantly dropped off when you tried
to start the engine, there are a few places to look.  I don't have a
yanmar, but this sounds like an electrical issue. 
	In most cases, the positive lead of the battery(s) goes to the
switch(s) that controll your selection of house and starting.  From
there the output of the switch goes to the panel for your power
distribution and to the engine for starting.  Your switch could be going
bad, dropping too much voltage so the starter tries to draw more
current, forcing more voltage loss, and when volts drop below about 10,
most electronics will drop off line.  So one place to check is the
switch.  Try just bolting the switch wiring together so that the battery
goes directly to the output terminal (the same one that goes to the
panel for distribution.  IF the engine starts OK, then the switch has
gone south, and replace that.  If you still have the symptom, then you
may have a bad cable to the engine or from the battery negative to the
engine block.  The end at the engine is invariably buried behind some
stuff on the engine, but you can just use a jumper cable from the
battery negative to the engine block and see if things improve.  If not,
now you have eliminated the path from the battery to the block negative
side and the wiring to the solenoid.  About all that is left is the
soleniod and starter.  You can take both off the engine and have them
checked.  Since the current drain seems good (the dropping voltage says
you have current flow) and if the wires are good and not the source of
the droop in voltage, I would suspect the starter, so that is the piece
I would check first.

Regards,
Les H