Yanmar 30GM30F Non-Start Issue

[lorenzo123]

My 210 hour 1995 Yanmar runs fine first time; but after running for awhile and shutting down, it won't start. Lights and alarm come on, but no starter. If I let it sit for awhile, no problem. Is there a auto shutdown when hot from running perhpas? Lorenzo

[galynd]

by no starter, do you mean the starter isn't engaging? If yes, I'd clean the battery cable terminals. sometimes my 3gm30f will not engage the starter, all comes on, etc. It's generally the + cable at the starter. I clean all cable terminals at least once per year. I forget to clean that one, at the starter in the process, for some reason. Be carefull and disconnect the cables at the batteries before you start cleaning.

[DeepFrz]

Check to make sure the diesel tank vent is clear. A plugged vent can cause that type of symptom.

You don't give much information about the problem. Do you have to bleed the fuel system, etc. so that's about the best I can do.

[bljones]

This is a common complaint with yanmars. As suggested, clean all connections and then treat them to a coating of dielectric grease.

[perchance]

If it is a wiring/connection problem the resistance will increase with a temperature rise.

[DeepFrz]

Sorry, I misread your post. I thought that the engine stopped on its own but I now see you shut it down.

[senormechanico]

If it's like my old boat's 3HM35F, there is a plug and socket in the wiring harness of the engine. I believe it's near the transmission.
The pins are slotted and can be spread slightly.
Clean, spread them a little bit and Bob's yer uncle.

[MSN-Travelers]

I had this same problem on our new-to-us `99 Beneteau with a Yanmar 30GM30F. My internet research found that this is a common problem. It doesn’t matter who built the boat, the engine wiring is supplied by Yanmar. It seems the circuit that feeds the starter solenoid has a very long run and uses a marginally sized wire gauge. The current drop at the starter solenoid is so high that it will not engage, and keep the starter engaged, if there is any corrosion at any connector in the circuit.

I may have the wire size numbers wrong but I seem to remember . . . The wire that feeds the pedestal (i.e.: key switch) is something like 10-12 gauge and the wire that goes from the starter button/switch to the starter solenoid is something like 14-16 gauge. Sometimes, this light weight wire has trouble passing enough current to power up the starter solenoid and engage the starter.

A number of us have resolved the problem by putting a starter relay (momentary contact type like those used on Ford & Chrysler vehicles) between the battery and the starter solenoid. The wire that leads from the starter button to the solenoid is routed to the relay. The relay is installed so that relay feeds the starter solenoid direct from the battery.

With the installation of the starter relay, the old starter button part of the circuit only has to trip the relay and the relay energizes the starter solenoid direct from the battery.

We haven’t had a “push-the-button and nothing happens” incident since installing the relay.

Hope this helps.