Starter Motor spins but won't engage

Mustang1500

Recruit
Joined
Jan 22, 2005
Messages
3
Hello everyone! Thanks for the great forums which have answered some of my questions already but I am stuck on this one. Recently the starter motor on my early 1970's evinrude stopped working all of a sudden so after investigation I found a broken wire from the negative? brush to the windings?. After soldering this I re-assembled starter but cracked the fibre washer? that holds the brush housings. I finally put it all together and fitted starter to O/B abd it was good as gold. Today I decided to do a better repair so I stripped down starter, did repair and re-assembled but when I fitted starter to O/B it seems to be spinning in wrong direction and the Bendix won't engage even though it is free on the shaft. The battery is new before Christmas. What could I have done wrong? Something inside starter or reconnected wires wrong?<br />Greetings from Australia <br />Regards Peter
 

llfish

Senior Chief Petty Officer
Joined
May 2, 2003
Messages
695
Re: Starter Motor spins but won't engage

Did you remove the gear that engages with the flywheel. If so could you have put in on up side down. Check and make sure that you have the correct polarity.
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: Starter Motor spins but won't engage

G'Day Peter.<br /><br />Welcome to iboats. :) <br /><br />If you accidentally got the wiring of the brushes (to the armature) reversed it would make the motor turn in the opposite direction. That is what fish means by polarity.<br /><br />Easy mistake to make.<br /><br />Good luck. :)
 

Mustang1500

Recruit
Joined
Jan 22, 2005
Messages
3
Re: Starter Motor spins but won't engage

Thanks for your prompt reply. It is just after 11.00pm so I will check out your suggestion tomorrow and let you know what I find.<br />Tight Lines.<br />Peter
 

agitator

Petty Officer 2nd Class
Joined
Sep 29, 2004
Messages
194
Re: Starter Motor spins but won't engage

Be sure you haven,t got your battery cables reversed.
 

Mustang1500

Recruit
Joined
Jan 22, 2005
Messages
3
Re: Starter Motor spins but won't engage

Thanks for all the help, I got the motor running today.<br />I'll address each suggestion in order.<br />No I didn't take bendix off.<br />The type of starter could not be put back with the brushes wired wrong.<br />No the batery leads were not reversed.<br /><br />Now for the solution: Firstly I hot wired the starter and it ran backwards so I knew it had to be inside the starter. I pulled the starter apart several times and always got the same result - everything seemed OK. After a short test of the starter I noticed that the body of the starter was quite warm which got me to wondering so I pulled it apart again and carefully checked everything. What I eventually found was a small split in the insulation of the +ve wire to the brush which was allowing current to ground out. I have no idea why this caused starter to run backwards but after taping over the split, assembling, fitting and trying to start O/B it worked!!!!!<br />I only have one more question: Does this mean that I am demoted from my newly aquired rank of Cadet?<br />Going fishing next W/End so hope for a feed.<br />Thanks again and regards from Peter
 

ob

Admiral
Joined
Aug 16, 2002
Messages
6,992
Re: Starter Motor spins but won't engage

If the positive brush lead of the starter motor was arching to ground it may have reversed the polarity or limited the motor speed below sufficient to thrust the bendix..This is DC voltage and one leg is grounded.Otherwise I'd say you could retain your Cadet ranking.Carry on. :)
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: Starter Motor spins but won't engage

A grounding of the positive line between the brush and the armature would cause the motor to run backward as a shunt wound, rather than a series wound, motor.<br /><br />Running as a shunt motor, it would not develop enough torque to start your engine anyway.<br /><br />Nice troubleshooting, Mustang. :)
 
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