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Yamaha Outboard Electrical Problem

1572 Views 7 Replies 5 Participants Last post by  Glyndoree
Hello, I am hoping someone may be able to shed some light on a problem I have with a 2 stroke 1983 70HP Yamaha Outboard, I am a complete technical numpty so please forgive some of my descriptions:

I decided to recharge and install the battery so that I could use my boat. However, when I tried to start the engine the solenoid just makes a clicking noise and the starter motor does not turn over. I also smelled burning which turned out to be a wire coming from a block located just above the gear box and which runs to the engine mounting. The wire is obviously some sort of earth. My first thought was that there must be a bad earth somewhere in the system. I re made and cleaned all the connections from the batteryand isolater switch to the engine. I then checked with a voltmeter.

When running the volt meter from the live in and the earth on the starter motor I get 12.50 volts therefore there is definetly enough power going into the solenoid and the earth back to the battery through the isolater is also sound. The trim and tilt also hardly works and again sets the wire from the block thingy on fire. I feel that the problem must therefore be with the engine wiring somehow?

All was fine the last time the boat was used back in September. Any ideas gratefully received. Thanks in advance.
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Check out and clean every negative/ black connection from the battery to the starter. Check that the terminal ends are still connected to clean wiring along the wires. Sounds to me like an earth fault, a corroded terminal or connection will pass a voltage but not handle the high current that the starter demands.
Hi ChrisP,

Thanks for your reply. I have already re made and checked with a voltmeter, all connections from the battery to the isolater and isolater to engine. I am pretty certain that the problem is not in the wiring in the boat e.g. from the battery to engine and engine to battery.
I`m with ChrisP.
A clicking solenoid and the starter not turning is a classic case of a bad connection from the battery to the starter. Had it the other week on my friends boat, first place i looked was the battery, cleaned and refited the terminal connectors and the engine started.

Alan
Thank you for the advice. I have now remade every connection with new crimps / terminals including trimming back and stripping all cables to reveal new shiny metal and now everything is as it should be.:)
Glad you are sorted, it could only have been a corroded/poor connection with the symptoms you described.

Do yourself a big favour now and get a tub of vasseline and pop it in a pan of water until it is liquid. Dip each one of your crimps in it and about 6mm up the insulation. I will seep into the crimps and strands of wire and stop the corrosion in the future.
Glad you are sorted, it could only have been a corroded/poor connection with the symptoms you described.

Do yourself a big favour now and get a tub of vasseline and pop it in a pan of water until it is liquid. Dip each one of your crimps in it and about 6mm up the insulation. I will seep into the crimps and strands of wire and stop the corrosion in the future.
just to add,you can get HEAT SRINK crimps that are designed just for this purpose,but they are expensive,
I had this same problem last year. Turned out that the actual leads had deteriorated. Replaced the leads with an old set of jump leads, soldered new connections on the ends and vasselined, it now starts perfect every time.
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