Jump start of Yanmar 3YM20

[Charlotte14150]

I have a 2006 Yanmar 3YM20 in my Catalina 309. It did not start twice. After the first failure in June 209, I replaced both 3 year old batteries, but it still did not start immediately, only after I pushed the starter switch couple of times. Since then, as a safety measurement I carry a thick automotive jumper cable on the boat. The second starting failure occurred 2 days ago. I thought that it was no problem, I had a jumper cable. I got out it and connected one end of the black cable to the negative terminal of the starter battery and the other end to a metal part of the Yanmar motor. Then, I connected one end of the red cable to the positive terminal of the battery and I touched the other end to the screw where a red cable is tied to the starter motor. Nothing happened, not even a click. I even tried to connect the black cable to the ground connector of the starter motor with the same result. After all of these, I accidently touched the red cable to the body of the Yanmar motor creating big sparks. But the motor started. I also lubricate the red cable coming to the starter regularly without taking it off.
Could anybody please give me some ideas how to jump start my Yanmar in emergency situations?
Thank you.
Tibor Gyires
2006 C309 #30 "Charlotte" St. Pete Beach FL.

 

[tahomathundr]

Tibor, You may want to take the red cable off at the starter and use some emery cloth to rough up the contact surface then reinstall your cable. You could have some corrosion under that lube on that contact area. I would check the black cable also. Another possibility to check is the cables themselves. Check the cable ends for corrosion also. Another slight possibility could be if the cables are stretched too tight or too loose and flexing with too much movement they can breakdown inside the cover. Starter cables need alot of juice to start that engine, so if there is corrosion or some strands are broken on the cable it doesn't get enough. When you touched the red cable too the block it may have burned through corrosion or welded some broken strands giving you a temporary electrical connection but this can damage other electrical components such as alternators. Make sure you disconnect the battery before checking for corrosion. This is something you can check before you call in the pros. I hope this helps. Bob P. C309 #20 "Big Luv" Seattle WA

 

[Charlotte14150]

Bob,

Thank you for the tips. They are very useful.

Tibor