81 starter switch

Hello all!
You guys have been absolutely helpful with my last post on here regarding my 81 ski nautique not turning over. Turns out it was a bad starter and bad terminals at the battery. I recently had to replace a part of the floor which took some time getting back together. Pretty much all summer. Now I have a new problem, and I am hoping you guys can help me out yet again. I recently tried taking the boat out and the starter switch on the dash seemed to not work. I went out and bought a new starter switch and replaced it. Matching all the terminals together the way I took it off. It started to crank but then stopped, I though I might have not tightened then down and one may have worked loose. I turned the switch to off and took the key out. When I went to place the screwdriver on the screws in the back to make sure they were tight the boat started to turn over and crank. I did not slip in the screwdriver at all potentially jumping the ign and starter terminals. I tried doing it with all three terminal ends individually and it did the same same thing with exception of the battery end of the starter switch. I am thinking I have a wiring issue and I am open to all suggestions if anyone is willing to help.

I never did find a voltage drop from the last time. I know I have not posted from my last post on here, which I apologize for. I ended up getting super busy working on the floor and also traveling for my job. I ended up changing the battery terminal ends on the wires, the battery itself and also the starter and it seemed to work as advertised. This is a new issue that arised yesterday. I will have to go and find that diagram and follow some wires. I am still baffled as to why when I place a screwdriver on the screwhead, on the ignition prong, the motor starts to turn over and crank. I have a three prong starter switch and I am wondering if the wires are crossed somewhere causeing it to be hot. But I don't know why my screwdriver is the thing that's causeing to complete the circuit. Again I am only touching one screwhead.

Maybe the switch's internal contacts are loose & when you pushed on the wire lug it moved & made contact.

Jon,
Check your wiring since it sounds like you may have the switch wired wrong or there's a cross connection between the switch and relay. When it's in the on/run position you should not have power to the start relay coil. Disconnect the battery and use the Ohm setting.

Also, I haven't asked or mentioned the battery. Hopefully you are using a starting type and not a deep cycle.

Highflyin504 wrote: I am thinking I may have it crossed somewhere. Like I mentioned before I took off the old terminals off the old switch and placed them on the new switch one by one. .

Jon,
Did the new switch have the terminals marked "B", "I" and "S"? Has the distributor been converted with an EI pointless requiring bypassing the ballast resistor?

Jon,
I was more or less thinking out loud regarding the EI conversion trying to give you an idea of were to look for wiring that's causing the start relay to energize. I have seen were wiring between the relay and ballast resistor has been mixed up when EI conversions are done. Since it sounds like you haven't done the conversion, so don't worry about it too much but, do follow that wiring diagram and check.

Have you done any other wiring changes/additions? Have you Ohm'd out the new switch to make sure it's not defective?

Out of the three prongs in the back of the switch should any of them be hot? And what should the voltage be on the back of the starter relay? I am going to assume that it should be 24v and when the key is on it should be zero until you turn the key over to start cranking the motor.. am I correct on that?

Highflyin504 wrote: And I have not tested the new switch yet. The weird thing to me was that it was working as it should when I first replaced the switch.

I've said it before, I'll say it again:
If it was working, and then you've changed something, and now it doesn't work, chances are very high that the problem has to do with something that was changed.