25hp Yamaha 4 stroke 1999/forward reverse issues/starting issues

[pd]

Was out in the skiff this weekend. It's an electric start.
When I pushed the button I could hear an electrical pop from where the positive battery cable joins the motor. Very faint pop. Couldn't hear it until I had the cover off. I pushed it for maybe the fifth or sixth time and it started right up. Basically had the same problem all day. Five to six tries then it would start no problem. Nothing like it before.

Getting ready to leave for the day, same problem, and this could be totally unrelated, but this time after it started and I put it in forward the boat went nowhere. I thought I was grassed so I put it in reverse to clear the prop and there was a crunching sound and then the prop started spinning. By that time I'd taken it out of gear and shut the motor down. Decided to give it another whirl, but this time the motor started right up without the hesitation. When I put it in Fwd it acted normal but as re putted down river I'd occasionally hear a slight grinding sound as if it were being shoved into reverse even though there was never any loss of power. Each of the times I stopped when it did that the motor restarted fine.

I think I have two problems here.

 

[robert graham]

Re: 25hp Yamaha 4 stroke 1999/forward reverse issues/starting issues

I believe one of your problems is corroded or loose electrical cables/connections. Best to take each cable/connection off from the battery, side of starter, etc., one at a time, clean it with a 3M Scotchbrite pad or similar, then just a touch of grease to keep out moisture , then tighten them down good. The other "grinding sound" sounds like something wrapped around your prop, or a shifter/gearbox issue. Fix the electrical part first then do the other...hard to troubleshoot 2 problems at same time. Good Luck!

 

[pd]

Re: 25hp Yamaha 4 stroke 1999/forward reverse issues/starting issues

Figured out the problem with starting. Loose nut where the battery cable comes in. I swear I wiggled that on the water and it was tight. In fact that was the first place I looked.

 

[pd]

Re: 25hp Yamaha 4 stroke 1999/forward reverse issues/starting issues

Starting issue back.
Any ideas how to test the starter relay? I'm getting 12V where the wires come in but the relay just makes a loud click when I push the starter.

OK, I put a meter on the ground and the little post on the relay that has the red wire. When I push the start button I get 12V.

So maybe not the starter relay...

 

[4x4xEric]

Re: 25hp Yamaha 4 stroke 1999/forward reverse issues/starting issues

Starting issue back.
Any ideas how to test the starter relay? I'm getting 12V where the wires come in but the relay just makes a loud click when I push the starter.

OK, I put a meter on the ground and the little post on the relay that has the red wire. When I push the start button I get 12V.

So maybe not the starter relay...

You maybe getting enough voltage but not enough amps, you might have a short somewhere that is "stealing " away the amps needed to work your solinoid. the intermitant operation could be cos its getting warm and moving the short apart.
Good luck.

 

[pd]

Re: 25hp Yamaha 4 stroke 1999/forward reverse issues/starting issues

Thanks, Eric.

Turns out it was a faulty solenoid/starter relay (for those like me, in this case--those mean the same thing.)

Attached to the relay are two large wires, red & black. The red goes straight to the battery's positive terminal, the black goes to the bottom of the starter motor.

The black/negative wire from the battery goes straight to the top of the starter motor, thus the starter motor only has two wires attached to it, both black.

Here's where I got a little confused. The black wire running from the relay to the bottom of the starter is designed to carry current when the relay is operational i.e., the starter button is being pushed. I was thinking "red&black" and when I held my meter leads on the red & black wires on the relay I got 12v--just what I thought it should be...Not realizing that that black wire when the starter button is engaged acts like a red wire normally would.

I'm sure the color coding makes sense to the electricians in the group.

As for the shifting. A friend had me look at the linkage nut that's visible without taking apart the motor (the one you'd loosen to take your foot off and replace your water pump). It was quite loose. tightened it and gave it a cursory run with the water hose attached last night (after replacing the relay). Seems to be OK. I hope to get it out on the water this weekend. If I run into any problems I'll post back.

(hopeful) Conclusion:

Starting problem was the starter relay/solenoid. As it was dying it provided me with a few starts but eventually went completely dead. To test your solenoid: Put your positive meter lead on the large black wire on the solenoid and your negative meter lead on a grounded area, push the starter button, you should read 12v if everything in the chain is good to this point.

Shifting problem seems to be the linkage connection nut that is visible (front of the motor) where the foot meets the rest of the motor. This linkage is best viewed with the motor in reverse. There are two nuts, one for linking the upper and lower linkage and another used as a stop nut to keep the former in place. Seems my nut connecting the linkages was not tight. Adjusted and the "slight grinding sound" was not heard.