Solenoid on Starter overheating Hunter 40, 1985

[Michelle D]

We are in a full-service marina who said it is having difficulty hiring a mechanic. Despite having a survey done before buying our boat a few months ago, we’ve only been able to sail a handful of days this summer due to problems with the boat. Anticipating a problem or two with a newly purchased boat we agreed to pay for an expensive marina. Despite this, they have not been able to help with any repairs. Our most recent problem occurred when a hot/smoky smell started spewing from our engine. The smaller wiring to the starter was melted and boat couldn’t be restarted. We put in a new starter ourselves after much research and difficulty. Sailed two times, everything seemed fine, engine purred along. Planned a 10 day trip, then same thing happened on day two, thankfully right BEFORE sailing into the East River in NY. Were towed back to marina, and here we sit, calling mechanics who already have full schedules. Any thoughts on the cause? Engine is a Yanmar 4JHE 44 HP.

[RocketScott]

What did you do to fix the melted wires the first time?

Buy a new harness or patch what you had?

[Michelle D]

Replaced entire starter.

[Jammer]

Originally Posted by Michelle D

We are in a full-service marina who said it is having difficulty hiring a mechanic. Despite having a survey done before buying our boat a few months ago, we’ve only been able to sail a handful of days this summer due to problems with the boat. Anticipating a problem or two with a newly purchased boat we agreed to pay for an expensive marina. Despite this, they have not been able to help with any repairs.

Sadly, this is common.

Our most recent problem occurred when a hot/smoky smell started spewing from our engine. The smaller wiring to the starter was melted and boat couldn’t be restarted. We put in a new starter ourselves after much research and difficulty. Sailed two times, everything seemed fine, engine purred along. Planned a 10 day trip, then same thing happened on day two, thankfully right BEFORE sailing into the East River in NY. Were towed back to marina, and here we sit, calling mechanics who already have full schedules. Any thoughts on the cause? Engine is a Yanmar 4JHE 44 HP.

There are lots of possible reasons. As a rule I don't provide electrical troubleshooting advice online, but I'll make an exception here.


1) It is possible that the terminal on the end of the wire is failing and can just be replaced.


2) It is likely that the wiring to the solenoid is undersized. It is common on Yanmar installations for a relay to be added to reduce the load on the wiring. The relay would be operated by the existing wiring and would switch power from a fused battery connection to the solenoid.


3) It is possible but unlikely that the starter solenoid is operating after the engine is started.


4) Mechanic's remote start switches, that attach temporarily to the solenoid terminals, are available. Like this: https://www.summitracing.com/parts/otc-3650 You could consider using that as a temporary measure, so you can use your boat until permanent repairs can be made.

[Michelle D]

Your input is greatly appreciated. They all sound like very good explanations which we can now look into. Thank you so much!!!