Intermittent starting

[jimtraskos]

Thanks Scott,
Where would that positive bus bar be located, about? I tore everything apart but never saw anything like that. Last night I ran a new #10 wire directly from the ignition switch to the solenoid. I left the old wire connected as well. Starts fine, but most times it does at the dock. Started fine before I ran the new wire. Won't be able to "test' it until the weekend, after sailing.
Also do you guys think that I have to have a relay? or will the new wire be enough? Too much amperage through the ignition switch without the relay?

 

[cajon409]

had same concern several years ago, the problem is that the size of wire going to the starter solenoid is to small, and over the years due to high resistance the voltage is to weak to work the starter. To find this you will need to perform a voltage drop when the engine,starter is hot. You could run a larger wire to the solenoid , but then you put a extra load on the starter switch. What I have done as well as several others is to install a aux starter solenoid (early Ford) or get a marine type at boat parts store and hook up to your starter. did this 3-4 years ago, no concern since. Was told to do this by several other hunter owners and have had no other concerns.

 

[mz4wheeler]

had same concern several years ago, the problem is that the size of wire going to the starter solenoid is to small, and over the years due to high resistance the voltage is to weak to work the starter. To find this you will need to perform a voltage drop when the engine,starter is hot. You could run a larger wire to the solenoid , but then you put a extra load on the starter switch. What I have done as well as several others is to install a aux starter solenoid (early Ford) or get a marine type at boat parts store and hook up to your starter. did this 3-4 years ago, no concern since. Was told to do this by several other hunter owners and have had no other concerns.

I had the same problem, and also installed the new starter relay. Here is a good diagram:

The relay I used was this one, which looks identical to the early ford:

Starting has been fine ever since.

 

[artboas]

I agree 100%

I had the same problem, and also installed the new starter relay. Here is a good diagram:

The relay I used was this one, which looks identical to the early ford:

Starting has been fine ever since.

The relay solved the problem on my 40.5. Had one interesting observation.
The engine only refused to start when there was a large ferry, cruise ship, etc. About to ram into us. Not exactly sure how Yanmar senses that, but it was a sure fire thing

 

[jimtraskos]

Re: I agree 100%

Well here we go again. I ran a dedicated #10 wire directly to the starting solenoid last week. After a weekend of sailing all was well until last evening. Both sails down just outside the channel home and no engine. (My bad for not trying it sooner.) After a couple of attempts she started and was ok after with one more stop she started fine.
I am definitely going to put in the aux. contactor like the drawings, and maybe a new ignition switch. Does it matter what size the contactor is? Amps?

 

[mz4wheeler]

Well here we go again. I ran a dedicated #10 wire directly to the starting solenoid last week. After a weekend of sailing all was well until last evening. Both sails down just outside the channel home and no engine. (My bad for not trying it sooner.) After a couple of attempts she started and was ok after with one more stop she started fine.
I am definitely going to put in the aux. contactor like the drawings, and maybe a new ignition switch. Does it matter what size the contactor is? Amps?

Takes quite a bit of current to energize the solenoid on that starter. The resistance of the primary coil is about 1 ohm, and since ohms law says:

Current = Voltage/Resistance

That is a current draw of at least 12AMPS (12/1=12), so size the wire accordingly (10AWG).

That is why using the starting switch on the console was always a bad idea. Your switch is probably OK.