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Mercury 50 EFI Electical Problem

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gdaniel

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"I have a Merc 50ELPT EFI, &#3

"I have a Merc 50ELPT EFI, '05 model, that blows the 20amp main relay fuse as soon as I turn the key. Trim works fine until I turn the key. Still under warranty but would rather not have to take it in and wait a week if there is an obvious/easy fix. Would greatly appreciate any help.

Greg."
 
"disconect all gauges and acce

"disconect all gauges and accesories and see what happens, reconnect them one at a time"
 
"Ok guys I hope someone can he

"Ok guys I hope someone can help me out. I have a 2005 Mercery 50 HP model 50ELPTO. I took the boat out two weeks ago, and tried to start it off the trailor and all is a wizzing sound when I turned the key. So me and my buddy trolled around the lake all dayyyy. When got it home turned the key and what i saw was the starter pineon gear was 1: was not ingaging the fly wheel and 2: spinning in the wrong direction. The was some chattering come from the starter silenode. So thinking that it was bad I changed it out, but it is still doing the same thing. Also to rule out the starter I used jumper cables from the battery that I have used all along to the starter directly, the starter then spun up and ingaged the fly wheel, and tried to crank the motor. Voltage checks that I have done where at the starter rely and I have 12 volts from the battery lead to the silenode. When I turn the key on I have 12 volts on the other side of the silenode(starter lead). So im getting 12 volts to the battery. When I checked the volts on the neg. side of the starter my voltage dropped to 5 volts, when the key is turned. I also disconnected the ground wire from the starter at the anchoring bolt to the voltage reg. and then took another reading on the loose end of the same wire then the voltage dropped off to zero. So i assumed that at the anchoring bolt of the voltage reg. there is another wire lug that has two black wires(ground). one of the wires goes to the oil tank sensor/swtich. and the other looked to me to go all the way under the console to the ignition swtich. I broke the connection at the igntion swtich wire connector and checked the continuity of that wire from the wire harness to the loose wire lug at the reg. anchor bolt. and read 0 resistance. Now just today I had a fellow tell me that with thw starter spinning backwards it looked as though the starter was wired backwards. as far as i know when i removed the starter silenode and replaced i wired everything up correctly. Remember the starter is doing exactly what it was before i messed with it. Please help me please. fishing season is here the crappie are hittin. Hopefully i've given you guys enough info. I'm really hoping that this is an easy fix. I'm not really wanting to spend an arm and a leg going to a dealer/TECH. Any info would be greatly appriected(im not a speller)."
 
"Do you say that it spins the

"Do you say that it spins the right direction with jumper cables, and wrong dir with key start?
If so, you have to check the polarity on your wiring between the motor and battery.

If the spinning is just "weak" with key start, you should look for voltage drop along the course wiring (use the negative reference directly on battery pole and move around the positive lead on your meter). The starter takes a lot of current, and only the course wires are feeding the starter (the key switch is just feeding the solenoid with much lower current).
On the negative side of the starter, you should read close to zero when cranking. If the voltage goes up (when cranking), you have a bad connection on the negative side of the starter.

The battery can also happen to be charged with reversed polarity. Check. If so you would have the same rotation also with jumper cables.

Robert"
 
"Hey Rob, first thank you for

"Hey Rob, first thank you for chiming in so fast. I thank you again. Now, I Just finished using the jumpers again on the starter and it's spinning in the same direction as it is with the key start the only difference is the starter engaged the fly-wheel and cranked the motor. I'm also using the exact same battery. So Rob, does that rule out a bad battery and starter? Help... What's next?
Ken"
 
"Engaging the flywheel means i

"Engaging the flywheel means it is spinning the right direction.
If it is cranking fast enough with jumpers, you got a good battery and starter motor.
Look for voltage drop in the course wiring, clean terminals etc (don't forget the negative side, good metal contact grounding to the motor etc). Have you got a main breaker switch? Look for hot spots (high resistance makes heat).
Next time I would advise to start your own new subject. Now, you kind of hijacked someone elses.
Robert"
 
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