Re: 1999 Evinrude 50hp 4 stroke No start, need t/s guide and controls wiring schem
Rick. You are aware this engine was made by Suzuki? So, some Suzuki literature will also be of help. But, til then, I have a possible answer to your wiring harness questions. You will have to start with the fact that The Suzuki wiring is "adapted" in the harness at the engine. If you have a Deutsch connector from the boat to the engine, you will notice immediately that the boat side of the Deutsch 6 pin plug is normal Evinrude wiring colors (red/purple = +12v source to key, purple = key on switched 12v, blk/white = ground, blk/yellow = kill, yellow/red = starter solenoid pick, and purple/white = choke.) Notice on the other side of that plug, the colors change to Suzuki colors. White = +12v source to key, grey = key on switched 12v, blk = gnd, blue/red = kill to EMM, brown = starter solenoid pick, and orange = "choke" even tho there is not one. OK....the only two wires you need to make it run are the first two, white and grey. Pull the Deutsch apart, and short the white to the grey with a jumper wire. The engine is now powered up enough to start, if nothing else is wrong. To kill the engine, simply remove that jumper. Now to your problem. When you jump those two wires at the harness, you should hear and feel the main relay click. If not, debug that grey wire back to the main relay to determine if the relay is bad, or if you have a wiring problem. Probe all white wires for +12v. The fuses are located in various places around the motor...there is more than one fuse. After the main relay picks, that supplies +12v to the ignition coil grey wires, and the fuel pump grey wire. The ground for the fuel pump is supplied thru the EMM. I hope this gets you started, and don't kill the messenger if this info is not accurate, as I am not using an Evinrude manual. A couple of other thoughts....you cannot use a normal 7/16 spark gap tester, because the spark simply will not jump that gap. Test for spark with the old plug in the boot and grounded to the engine method, or use an inductive timing light on one of the plug wires. The other sensors you mention will never cause the HP fuel pump not to operate. It is EMM controlled, and those sensors will not cause the EMM to refuse to run the pump for 10 secs at key ON time. You can always jump the "other" wire (color probably is black/white to ground at the fuel pump to see if the pump will turn ON then. White to grey jumper in place, of course. I have also removed the fuel rail, injectors in place in the rail, pointed the entire rail away from the motor, and cranked it to see/check for fuel shooting out each injector. Also, you can rig a fuel pressure gauge to the fuel rail, and look for 40 PSI at the fuel rail. These anr some minimum needs to get it to run. You can also squirt raw gas into the intake (really load it up) and see if it starts then. If so, you DO have spark, and the HP fuel pump is down. Got a tach? The tach should be blinking error codes at you at key ON time if the EMM has hard errors from any of those sensors you mentioned. I can give you the error codes if needed. Good luck.
