82 evinrude ignition problem (blowing fuse)

Red Rover · #1 August 26th, 2006, 05:14 PM

The other day I went to start my boat. And the ignition just fell apart, the back fell off. So I got a new one with 6 terminals, S C B M M and I, the only dif. is the old one had an A where the new has an I. So I hooked it up
S - yellow w/ red stripe
C - purple w/ white stripe
B - red w/ purple stripe
M - black w/ yellow stripe
I - purple
M - black

This was matching the old ingition except for the dif. between a and i . So I turn the ignition and click then the fuse blows. Any help would be greatly appreciated.

F_R · #2 August 26th, 2006, 05:44 PM

Sounds good. You are going to have to get an ohmeter and check out the switch and/or other wiring. The continuity readings on the switch should be:
Switch off: M to M. only
Switch on: B to I (A) only
Switch to start: B to I and B to S only
Switch to choke: Same as on and start, plus B to C. only

If the switch checks out, you have a short somewhere else.

Red Rover · #3 August 26th, 2006, 05:55 PM

F R, I do have an ohmeter, but what exactly do I need to do to check continuity. Thanks

F_R · #4 August 26th, 2006, 08:12 PM

Disconnect all the wires from the switch. With meter set at some mid-range scale, touch the leads to the specified terminals with key in specified position. Continuity will show as near zero ohms, no-continuity as near infinity.

I forgot to mention, there should NEVER be any continuity between either M terminal and any other terminal except the other M. That includes momentary contact when turning or pushing the key. I have a sneaking suspicion that it might have this fault, which would blow the fuse.

Red Rover · #5 August 27th, 2006, 03:05 PM

ok, so I checked out all the terminals and they all checked out. So I guess it's back to the drawing board, where else would be a problem area for a short?

ezeke · #6 August 27th, 2006, 04:00 PM

Isolate the short. It is either the choke solenoid [C], the starter solenoid [S] or something connected off the A [i] terminal.

The positive red w/purple is OK or it would blow the fuse before you turned the key.

F_R · #7 August 27th, 2006, 04:23 PM

Considering how tightly those wires are crammed into a small space, I would consider maybe the problem could be right in there someplace. Any wire that may have the insulation mashed would be suspect. Even adjacent wires where they connect to the switch if they lie tightly side-by-side. Another prime suspect would be where the purple wire connects to the hot horn; if it is bent down, the terminal could be contacting the horn body.

There really isn't much to go wrong other than bare wires. The switch feeds the hot horn, choke solenoid, tachometer plug, and starter solenoid. None of those are famous for shorting out in themselves. Resistance tests on each wire are necessary to isolate problems in those areas.

F_R · #8 August 27th, 2006, 04:26 PM

Well, I'd have to think about the comment concerning the horn. Hm-m-m-m

Red Rover · #9 August 27th, 2006, 05:23 PM

so, I changed the C, S, and I wires and the fuse is still blowing. I checked the continuity with the wires attached but the battery disconnected and there was continuity between M and C. Is that normal, or is there not supposed to be continuity between M and C even with the wires own.

ezeke · #10 August 27th, 2006, 05:45 PM

No continuity between M and C is correct.

M is the kill wire. When closed by turning the switch to OFF, it grounds out the power pack. Nothing else except your emergency cutoff switch should be on that circuit.

Red Rover · #11 August 27th, 2006, 05:56 PM

I'm sorry this is confusing to me, bet when the wires are attached to the ignition, and it is off, I have continuity between M and M, and M and C. If I take the wires off then there is no continuity between M and C, but stiil between the M's.

ezeke · #12 August 27th, 2006, 06:01 PM

Neither M should have continuity with anything when the switch is in on, start or choke, and only with each other when off.

Disconnect the choke wire from C and see if the problem stops.

Red Rover · #13 August 27th, 2006, 06:46 PM

alright good news, I disconnected C and it worked. So does that mean the choke solenoid is bad?

ezeke · #14 August 27th, 2006, 06:54 PM

Maybe. Could be the wiring. You could isolate that by reconnecting the C and disconnecting the choke solenoid wire at the motor.

I am a little concerned that you could get power to the power pack and damage it.

Check the choke solenoid wiring carefully at the engine.

F_R · #15 August 27th, 2006, 08:37 PM

You are confusing yourself and everybody else with invalid continuity checks. With the switch off and all wires disconnected, there should be continuity between M and M (not C). With the two M wires connected, they are both connected to ground with the switch off. But here's the rub: The choke wire is also connected to ground via the electro-magnet coil in the solenoid, albeit there would be a few ohms resistance....whatever the coil is. So, to make a long story short, what you are doing is connecting one ohmmeter lead to ground (M), and the other one also to ground through the choke solenoid. Result: a continuity reading. But it's an invalid test.

Tom Scully · #16 August 27th, 2006, 08:38 PM

"I have continuity between M and M, and M and C. If I take the wires off then there is no continuity between M and C, but stiil between the M's."
With the wires on the switch you will see the resistance of the choke coil between C and M because one of the M's is ground. So by reading the switch with the wires on you are essentially checking the choke soleniod and wiring by measuring arcoss M and C.

"alright good news, I disconnected C and it worked. So does that mean the choke solenoid is bad?"

Could be the solenoid or the choke wire is shorted to ground. The terminal on the choke solenoid is mounted in very close quarters, make sure it's not touching the block.