94 Evinrude 112hp still shutting down? HELP

[tbull]

Re: 94 Evinrude 112hp still shutting down? HELP

Also one more thing, upon further inspection I was testing out my warning horn that is hooked up to the 2 tan temp wires that come out of the 3 and 4 cylinders I believe. I disconnected the wires from the #4 cylinder, and grounded it to see I got a horn and I did, I attempted the other wire on the #3 cylinder and the connection was so badly corroded that it would not even sound the horn when grounded, I had to snip off the two leads on each connector, and put new connectors on and then I got a horn when I grounded the lead this time. I guess my question is, would something like that cause any kind of problem while running if the connection was that badly corroded? Maybe sending a false overheat warning or something?

 

[tbull]

Re: 94 Evinrude 112hp still shutting down? HELP

Dont want this to get lost, any info guys?

 

[ezeke]

Re: 94 Evinrude 112hp still shutting down? HELP

The tan wire is a ground wire for the warning circuit. The corrosion is a concern in that you may have more of it in other wiring connections and I would suggest that you make a full examination of the connectors throughout the system.

The sacrificial anodes on the motor are critical to reducing corrosion and should be carefully inspected and tested with an ohmmeter for continuity. Whenever possible, the battery switch should be turned to "off" when the boat is not in use. Generally, the only device that should bypass the battery switch would be the bilge pump.

Your fuel tank may be aluminum and may have contact with a ground, especially if the boat is aluminum. It is hard to completely isolate the aluminum boats from the battery ground since the motor is grounded and clamped to the boat.

 

[tbull]

Re: 94 Evinrude 112hp still shutting down? HELP

That ground makes sense, it is an aluminum boat, I guess the jumping around on the gauge when I move the main power wire probably indicates a bad wire correct? The wires on the harness looked ok, given they were covered in a black mess from the electrical tape they used going to crap over time. We removed the tape from the entire harness and wiped the wires clean looking for shorts in the wire. How would I test each wire with an OHM meter? what should I be looking for as far as readings? Would it be one of those deals where one guy holds a lead at the ignition switch and another at the end of the wires?

 

[ezeke]

Re: 94 Evinrude 112hp still shutting down? HELP

You can buy small, insulated alligator clips at radio shack and use them for longer runs of new wire. The clips are usually in the drawers where they keep the small electric contacts, fuses etc. Make up a pair of wires with clips at each end so that you can snap them in place and control the ohmmeter.

Then disconnect the battery and connect your negative ohmmeter lead to the negative battery cable (not the battery); you can then test all of the negative circuits including the ignition switch and the anodes for continuity. Each wire in the main harness big red plug can be checked in either direction.

If you are experiencing erratic actions on your tachometer or on your voltmeter, I would strongly suggest disconnecting the rectifier and taping off the leads until you finish troubleshooting.

Finally, the Troubleshooting Guide available for free download from CDI Electronics is a great help and has sections for each type of engine. http://cdielectronics.com/portals/0/downloads/Troubleshooting Guide 2006.pdf

This is a large pdf file so be patient and be sure to save it to disk so that you can refer to it when needed. If it is too large for your system to open online, right mouse the link and choose "save target as", to save it directly to your computer. Be sure to read "Tricks to Testing with Minimal Test Equipment" on page 4.

 

[tbull]

Re: 94 Evinrude 112hp still shutting down? HELP

If I check for continuity, would I get no continuity on wires that have a short somewhere? Also on pretty much any ground on the engine should have continuity or no? I would guess that if there is no continuity there is a short in the ground somewhere correct? Should I be taking specific ohm readings on the wires also? Am I looking for somthing similar in a rectifier where I should only get ohm readings in one direction? Also I just replaced this rectifier, but my tach still is not working. Even if the batteries are charging, could it still be a faulty rectifier if the tach still does not work?

 

[ezeke]

Re: 94 Evinrude 112hp still shutting down? HELP

When you turn the ohmmeter on, with nothing connected, you have no continuity. Any reading then would indicate continuity between the two probes. If you start at the battery cables and test the various wires, you can find most shorts.

For example, there are many wires that should not have continuity with the negative ground, but should always have continuity with the positive cable. The black and yellow kill wire should not have continuity with anything unless the ignition is off or the emergency kill lanyard is pulled.

If you connect the unregulated rectifier's yellow lead and the metal base, you should get no reading in one direction and a reading in the other direction and so on.

If you have a water cooled regulated rectifier, you can't really test it with an ohmmeter, so you should connect the gray tachometer wire to one of the yellow wires coming from the stator at the terminal block and see if the tachometer works. If the tachometer then works, the rectifier is probably bad.

 

[tbull]

Re: 94 Evinrude 112hp still shutting down? HELP

Right on thanks for all your help ezeke...