40HP Big Twin will not start

[CATransplant]

Re: 40HP Big Twin will not start

Wierd. OK, where's the old solenoid? Did you replace it on principal or was the old one bad? If it was OK, put it back on and try again.<br /><br />I don't have as late an engine as you have, so I have to ask this: Mine has its solenoid in a separate box off the engine. I'm assuming yours is mounted inside the engine cowling, right?

 

[Paul Moir]

Re: 40HP Big Twin will not start

Sorry, I overlooked that.<br />The reason why your bendix doesn't fly up and hit the flywheel is the battery is not charged enough. That's what will happen when they're low - the starter just spins. At this point, even if it did engage it wouldn't be able to spin the engine.<br /><br />But that isn't what's causing the problem. The little terminal on the solenoid that leads to the engine should be 0v when you crank it. This means there's some trouble along that wire, the wire between the vaccum switch and the cutout switch, or the cutout switch itself. If at all possible, measure the voltage on the base of the vaccum cutout switch when the engine is cranked. If it reads +12v, then there's something wrong with the throttle cutout switch. Take it off, clean it up, click it a few times.

 

[jchrans]

Re: 40HP Big Twin will not start

I believe that the old seleniod was bad, as it died on me ... was doing the same exact thing as this one .. nothing. My selenoid is inside the motor cowling.

 

[CATransplant]

Re: 40HP Big Twin will not start

OK, then Paul's your guy. I haven't seen that setup, so I can't really advise you properly. I'm sure you're going to get this sorted out shortly.<br /><br />I'm just so glad that the major problem is solved now. Your engine runs again! Whee!

 

[Paul Moir]

Re: 40HP Big Twin will not start

If you want to see the solenoid work, run a wire from the little terminal that goes to the outboard to ground. The problem is with the throttle cutout switch or the wiring in between. Both the solenoids are still likely good.

 

[jchrans]

Re: 40HP Big Twin will not start

Paul, you are correct. Connected a wire as instructed and the starter got power. The bendix still just spins, but now I know the seleniod is good. I measured the voltage coming out the side of the seleniod that goes to the starter after having grounded the terminal as instructed and it read only 1.83V coming out. No wonder it's only spinning.<br /><br />Now, since you say it is the throttle cut off switch and that I must "take it off, clean it, click it a few times". This means I have to remove the flywheel again ... doesn't it???

 

[Paul Moir]

Re: 40HP Big Twin will not start

No it doesn't. There's only one bolt that hold the bracket the switch sits on to the block, which is easily accesable from the side. <br /><br />To test if the switch is working when you have it out, set your meter to resistance/ohms, and measure between the wire terminal and the mounting bracket. It should be infinity ohms when the switch isn't pushed, and 0 ohms (or close to it) when the switch is pushed in.<br /><br />Yeah, that battery is currently dead. Fully charged a car type battery will read 12.6v. Almost fully discharged it'll read 12.0v (with nothing connected).

 

[jchrans]

Re: 40HP Big Twin will not start

Okay, I took the flywheel off anyway and removed the switch, cleaned it, filed the bottom of it and the mounting brakent it sites on, tested it with my GB "GDT-185A" ... only I don't really know how to read ohms. with power on and it set to ohms, I get a "1" to the far left. with the swtich in or out (same reading for both) it starts out a negative number but works down to a positive 004.

 

[jchrans]

Re: 40HP Big Twin will not start

I think the switch is broken. I replaced the wire, so I know that isn't it. Does anyone know where I can find a new one?

 

[jchrans]

Re: 40HP Big Twin will not start

I replaced the switch ... and IT WORKS!!!! Purrs like a kitten! Starts every time (charged the battery too... obviously).<br /><br />I can't thank you gentlemen enough for all of your help! I would never in a million years have ever found or fixed these problems without you! You are super, wonderful people and I thank you with all my heart!

 

[jchrans]

Re: 40HP Big Twin will not start

 

[daveswaves]

Re: 40HP Big Twin will not start

Thats the ground I was talking about