Yamaha outboard c115 tlrr v4

[hurricane34]

First of all when you turn the key over to start it the rpm gauge jumps to 7 thousand rpms. It wont start then when it does start the tach jump back and forth and then settles down and then read right.I have had it cut off on me in the middle of running like it just lost voltage.But with the battery charger hooked up and let it set for a min it will start right up and run great.I take it to the lake with a fully charged battery and will turn over but will not start.I was think that the rectifier/voltage regulator was the problem.Any help would be greatly appreciate.

[VectorPat]

Your regulator will effect charging and tach operation but the engine should be able to run. That engine has a mag cd ignition. It is possible for the engine to crank over too slow and not start but once started the battery could be taken out and still remain running. You may be fighting 2 different issues.

[Jason Johnson]

run it on a diff control box, no need to transfer shift cables, just to check electrical, sounds like a switch or harness problem

[hurricane34]

I have tried it on a different control box and never got it to start the first time i had the problem.It sat for awhile until I could get to it and take it to the shop.But when I took it in they were checking everything over and their was no voltage and then all of a sudden they said it just fired right up everytime after that.I took it home did the same think but it died once right in the middle of running like the spark just died but it is getting fuel.

[flabum1017]

Check the battery cables for bulges,,, bulges can mean an internally corroded cable. Check the connections for cleansliness and tightness.

[hurricane34]

The negative battery cable was about to fall off the terminal I changed that the first time I was having the problem.The boat is a salt water boat from florida.The negative cables are not the shine copper color as the positive cables.I am going to buy new ones just to have a piece mind on the cables.