Yanmar starting hiccup?

[SeacretSailor]

Quick question - Should I be concerned?

About 20% of the time, when I go to start my Yanmar 2QM15, I'll push the start button and hear the starter spin, but won't hear the engine/flywheel turnover. It's a quiet non-starting action. I'll stop, re-press the start button and then it'll engage and start perfectly.

Normal, or the beginning of a starter issue since it's only every 1 out of 5 starts?

Thanks
Kev

 

[Ed Schenck]

That problem is related to one that I and many others have fixed. Because of the long run on smallish wire the solenoid is just barely getting enough amps. There are just two many connections between the battery and the solenoid. And the wire is too small. I tried a new 900CCA start battery, a new ignition switch, a new start button, replaced some wire, and added new connectors. The problem remained. The solution was to add a relay, actually a second solenoid. All who have done it had no further issues: http://hunter.sailboatowners.com/in...&cat_id=38&aid=7175&page=article&mn=37-cutter .

P.S. that was a 2QM20 by the way. And also had starter rebuilt, forgot that above.

 

[Ray Bowles]

We did the same thing on VW's using a Ford starter relay. It's a cheap and easy fix. Ed's web link explains how to do it.
Good Luck, Ray

 

[RichH]

VERY common problem on QMs and QM control panels --- HIGh resistance in the primary circuit wiring ... including the primary circuit's engine mounted FUSE holder (normally located on the port side rear of the engine on the flywheel housing).

The fuse is the most common high resistance culprit - corroded connectors on the fuse holder. Corrosion in any of the connectors along the whole primary circuit can cause the HIGH resistance, hence voltage drop. Other 'famous' sites: the starting push button - build up of carbon deposits on the contact surfaces - clean or replace. Any high resistance will develop low voltage and HIGH amperage requirements and the high amperage will 'char' the contacts of the keyswitch and panel start 'push button'.

Suggest you first clean or replace the fuse holder assembly. Then starting with the key switch check the resistance / voltage drop across each component, and wire until you get to the solenoid primary connection - replacing or cleaning each component as necessary. You will probably have to do this checking/cleaning/replacing on a regular basis as the WHOLE control panel and primary circuit is NON-tinned wiring. For 'emergency starting' to deliver correct voltage to the solenoid install a jumper + push button between the (+) HOT terminal on the starter and the primary connection to the solenoid ... and when the Yanmar control panel (yet again in the future) corrodes and develops high resistance, simply locate the emergency starter button and energize to start because in an emergency you dont have the time to 'futz around' tinkering with corroded and high resistance components or even cobbling together a 'jumper' (or screwdrive) across the solenoid terminals to engage the starter.

For best results .... Rebuild the WHOLE control panel with tinned wiring and tinned connectors, etc. if you want to completely remedy the situation on notorious Yanmar control panels .... and put a remote 'push button jumper', all set and ready, to 'energize' the solenoid + starter as 'extra insurance'.

 

[Bill Roosa]

Solenoid issues

Well I have to disagree guys. The standard solenoid "wires-connectors making too much voltage drop" problem has the following symptoms:
Hit the start button and you get a click but no starter turning.
SeacratSailor has a hit the start button and the starter turns but the bendix does not engage the starter pinion (little gear) with the flywheel gears. AKA spin but no click
A totally different problem.

FOR THE RECORD the solenoid does two things then the starter button is pressed
1) The voltage applied at the "S" terminal (starter button wire) energizes the solenoid coil and makes a magnetic field which draws the bindix into the flywheel. This mechanically connects the two
2) The bindix continues to move and completes the high current connection between its battery terminal and the starter motor causing the starter motor to turn and the engine to turn and hopefully start.
The problem with the normal "Hunter starter problem" is the bendix has two different spring rates for the two items above. A weak one that allow the gears to engage and a strong one for the electrical connectors to make contact. There are several engineering reasons for this which I will not go into here. Suffice it to say that the low volts on the solenoid "S" terminal can only draw the gears together but are not strong enough to compress the bindex to make the electrical connection to the starter motor. Hence the click and no spin.

SeacretSailor has the opposite the bendix is not moving the pinion gear into the flywheel but the high amp contacts are being made. This is an indication of a bindex/solenoid failure as the gears HAVE to engage FIRST and then the motor turned on. Something is broken inside the solenoid.
I'd try pulling the starter and with an thought that you are going to have to put it back together take the bendix apart. It may be that something is just warn and it needs replaced or it may just be gummed up with dirt. I'd say the starter motor is fine since it turns over the engine when the bendix does engage.

 

[Tim R.]

Sounds more like a faulty Bendix gear.

 

[bria46]

I agree, but in addition have your starter motor checked out by a qualified automotive tech.

 

[shemandr]

And ... you should be concerned. Murphy's Law clearly states it will fail to start as a ferry is bearing down on you and the wind suddenly dies. Or when you're transiting an inlet with swift current and being dragged into the jetty. These have happened to me and there are a few more.

 

[Scup]

All who have done it had no further issues: http://hunter.sailboatowners.com/in...&cat_id=38&aid=7175&page=article&mn=37-cutter .

Ed:
What size Cole Hersee solenoid did you use for your fix (that is, how did you size it?)
Thanks.