Logo
FULL SITE MENU

electric start problem on mercury 20

J

jet drive

New member
new member here with a problem. i recently bought a super clean 96 mercury 20 horse motor. tested it on the water before buying. owner said electric start works but starter is slow. it pull starts just fine. i decided to fix the electric start and here is the problem. old starter on hot battery would barely turn flywheel. crossed the syleniod and same thing happens. got a new starter and it still wont hardly turn the flywheel. its real slow. i can turn it by hand and it pull starts fine. checked all connections. so i hooked the starter up direct bypassing everything else to a hot battery and neither starter will turn the the flywheel very fast.
i am no mechanic but this isnt my first mercury to own either. what could be wrong? please help
 
Those starters are hard to find and $$$, so try this: Pull the starter apart, clean the armature until it's shiny, oil the bearings, and put her back together. That usually makes then run like new.

Jeff
 
i got a new starter and hooked it up direct to my running truck battery. it just barely turns the flywheel. very slow a little at a time, both starters do the same thing. i thought that hooking the old one up direct that it was the problem, but the new starter does the same thing, even hooked up direct. i cant figure this out. i cant see the new starter being bad, it does exactly the same thing as the old one. is there anything else it could be? why would both starters do the same thing? is there something i am missing?
 
The grounding cable to the starter may be corroded internally. Try cleaning the connections before replacing it. Use a set of quality jumper cables to substitute the starter cables to see if it will turn over.
 
Take the old starter apart and inspect / test it !!!-------Always inspect / test before running out to buy new parts.
 
Look for an automotive electrical store near you they specialize in starters and alternators. Take it in there and ask them to test it. You can buy bad starters. But in your case I doubt both of them would be doing it. Agree with above. Bypass the cables and go directly to the battery with jumper cables. Try jumping from a battery in your running vehicle.
 
hook a multimeter on 20 volt dc scale directly across battery and turn key to start and record reading...then move positive lead to pos term on starter...key to start and record reading...should be same reading unless you have a drop in connection or bad cable to battery...you can do the same thing on the ground side by moving negative lead from battery to a unpainted bolt or something on the block...you are checking for a bad ground or a bad lead from negative post on battery...
 
all of your voltage drop should be across starter....one thing to remember..you will not read a voltage drop without drawing current...you must be turning(or trying to) starter to troubleshoot this...
 
as stated in my first post, i did all that already. i hooked the old one up to my running tacoma bypassing everything but starter, it barely turns it, just a little at a time in short bursts. that why i got a new starter. then the new one did exactly the same, even hooked up direct to my running truck. thats what i dont understand, why both do exactly the same thing, ran direct to a running truck. both just turn it a few inches at a time in "bursts". but it pull starts and runs fine. any other ideas. all info is appreciated.
 
i am not a fan of jumper cables to troubleshoot...if you use a meter you will be able to pinpoint the problem either to the starter or a connection or cable etc..its possible you have two defective starters or two good ones...troubleshooting is the way to go...
 
Pull the plugs and see (by hand and on the starter) how easily it spins over. If it does not spin fast, the lower unit could be bad, or the crank bearings are dragging.

Jeff
 
fast jeff== I pulled both plugs out and I can turn it easily by hand and the old starter will spin it fast, a constant smooth spin.
I can turn it by hand with the plugs in and it pull starts fine also.
Any others ideas?
Its fixing to go to a mechanic and let him worry with it. I cant figure it out.
 
Back
Top