SailNet Community - Reply to Topic
Thread: Yanmar 1GM10 won't start Reply to Thread
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

  Additional Options
Miscellaneous Options

Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below

  Topic Review (Newest First)
08-01-2014 06:00 PM
Re: Yanmar 1GM10 won't start

also check if you have battery selector switch could be bad and only letting enough current through to kick solenoid in had that happen to mine make sure you have continuos 12v to starter side when trying to crank
07-31-2014 11:26 AM
Re: Yanmar 1GM10 won't start

Yanmar engines are NOTORIOUS for failing to start ... usually caused by corrosion in the primary circuit wiring of the starter solenoid circuit and most often corrosion in the wiring of the in-line FUSE holder that protects this circuit; but, can also be carbon build-up in the starter button switch, etc.

How to test: find/identify the battery lead from the battery that connects to the STARTER. Take an old screwdriver and 'short'/jump the Batt terminal on the starter to the center connection on the solenoid. Make sure your necktie and clothing dont get 'wrapped up' in the engine vee belts when youre leaning over the engine when 'jumping' the starter/solenoid!!!! If this engages the solenoid and the starter turns freely and with power .... repair the solenoid primary wiring circuit - keyswitch, starter button, FUSE holder, and all the connections between the starter switch and the solenoid.

Yanmar still uses non-tinned wire, non-tinned connectors and non-tinned switching components in their engine control panels, which are readily subject to corrosion (corrosion leads to high resistance and HIGH amperage draw) .... best is to 'rip it all out' and replace with TINNED wiring and components.
07-31-2014 08:02 AM
Re: Yanmar 1GM10 won't start

had similar problem on ysm8 yanmar after rebuild still same problem put new head on running like a champ
good luck
07-31-2014 07:56 AM
Re: Yanmar 1GM10 won't start

same thing happen to my ysm8 rebuilt didn't fix turned out head had rusted through replace running like a champ now
good luck
05-10-2008 03:48 PM
Conclusion... ?

As per bubb2's suggestion I read through the thread at:

There was a lot of discussion about the ability of the power cable leading from the control panel back to the solenoid to provide enough current to operate the solenoid.

What a few people suggested was putting a solenoid in place between the start circuit and the starter solenoid. Whoa... wait, huh? Yeah, a solenoid to power a solenoid. Crazy I thought. I still think it is crazy, but I think it will work. Rather than spending a good chunk of change on the solenoid I figured I would first confirm or disprove this solution. I ran a 10ga wire direct from the battery, through a properly sized fuse, to a properly sized off/on toggle switch (momentary would have been better, but this is just for testing) and then 10ga to the solenoid where the start button would normally feed to.

Well what do you know? The starter spun up with no problem!! I repeated the test a couple of times (allowing proper time during test of course). Yep. it works. Unreal!

So now I'm torn between re-wiring back to the control panel or going the "stepper solenoid" route. I'll probably go the re-wiring route first since it would not cost anything to try.

Thanks again for everyone's assistance! You guys (and gals) rock!

05-09-2008 09:31 PM
Check the plugs

No' not the spark plugs.
Until about three years ago , I had a Yanmar 1GM, the earlier version of your engine, I fought a yearly battle with the control harnes that ran to the engine. It wasn't a very weather tight connection. When the plug that connects the starter switch to the started selenoid would come loose, it would do nothing. Even if it looked good, I sometimes had to clean it before I could get a response from the starter.
05-09-2008 09:04 PM
bubb2 This thread may be of help to you. For those of us that have Yammar's your problem is not unheard of.
05-09-2008 08:54 PM
Originally Posted by rperret View Post
hopefully you're engine is not hydrolocked - i hydrolocked my Saab 9-3 when i drove thru a shallow puddle - the air intake in the Saab is low. what a fiasco that was.
Nope not hydolocked. Still working on it. Ugh! It's no wonder we refer to these boats as "her" and "she" ;-)

05-09-2008 08:20 AM
rperret hopefully you're engine is not hydrolocked - i hydrolocked my Saab 9-3 when i drove thru a shallow puddle - the air intake in the Saab is low. what a fiasco that was.
05-08-2008 11:22 AM
It just might be

The battery cables. It is not uncommon for the battery cable to be bad at the terminal itself. Remove the cables from the batteries and ohm them out. We had one at the marina that would make contact and show good 12 VDC. but when you tried to start the engine the mechanical connection between the battery cable and terminal would break down.
It can drive you crazy.

Fair Winds
Cap'n Dave
This thread has more than 10 replies. Click here to review the whole thread.

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

For the best viewing experience please update your browser to Google Chrome