1991 Mercury 40 HP Outboard - Starter turning backwards.

[hpnme]

1991 Mercury 40 HP Outboard - Starter turning backwards won't start. Removed the battery for winter storage, no work done on motor over the winter. Installed the battery and tried to start and starter is turning backwards (counter clockwise). Can anyone help?

 

[Chinewalker]

Did you install the battery backwards? Red to positive, black to negative...

 

[hpnme]

The cable ends are black and white. The white cable end will only fit on the positive terminal.

 

[StarTed]

I'm with Chinewalker on this one. The only way the starter will run backwards is if the battery voltage is reversed.

1. The battery is wired in backwards.
2. The battery ran down and was charged backwards

 

[Chris1956]

Well, there is another way the starter will turn the wrong way. That can happen if you have a permanent magnet starter, and you filp the magnet over, when the starter is apart.

 

[StarTed]

Good point Chris1956. I am not familiar with that starter but the OP said that no work was done over the winter.

Maybe the night shift did something. :laugh:

 

[hpnme]

The positive cable will only fit on the positive terminal so it is impossible to connect the cables backwards especially since the cables were never removed or repaired. They are exactly as they were when they were disconnected. This battery started the motor last season and was not charged before or after it was disconnected. Can low voltage cause this issue? I haven't tested the battery voltage. No work was done on the motor at all so the starter was not taken apart. I'm really new at this so I appreciate all the help and yes Ted, I am leaning toward a disgruntled neighbor!

 

[lmuss53]

The only way this thing can spin backwards is if the battery cables are backwards. I have done this before on a 1995 Merc 90, I'm not sure why you say the positive cable won't go on the wrong post, mine bolted right up.

Trace the wire from the negaqtive lead to the engine if it goes to a ground you are OK, if it goes to the solenoid it is backwards.

I lucked out but I have heard of folks frying the CDI box making this mistake,

I have seen the bendix hang up on starters making folks think it is not spinning in the right direction, a couple shots of PB blaster and a 5 minute wait help that.

 

[60sboater]

I'm with them...any DC motor can turn either direction,depending on how the pos and neg leads are connected to it. Low charge on the battery should not cause this. If you have a volt meter,test the battery (or take it to a place that will do it). Make sure the meter leads are red to + and Black to - then connect to the batt terminals and see if the battery shows show +12 volts or higher. I don't know if a battery can goof-up internally but give it a try.

Is your starter motor well grounded to the engine(shooting in the dark here)?

 

[lmuss53]

Can you post a picture of your battery with the cables on it, and possibly one of the connections under the motor hood?

Does the radio work?

 

[hpnme]

The positive cable will only fit on the positive terminal so it is impossible to connect the cables backwards especially since the cables were never removed or repaired. They are exactly as they were when they were disconnected. This battery started the motor last season and was not charged before or after it was disconnected. Can low voltage cause this issue? I haven't tested the battery voltage. No work was done on the motor at all so the starter was not taken apart. I'm really new at this so I appreciate all the help and yes Ted, I am leaning toward a disgruntled neighbor!

 

[CharlieB]

You still need to do the simpple + and _ tests. I have seen a few batteries that did reverse polarity while sitting for long storage. Neither was dead. My clue was the dead short when connecting the two batteries in parallel in the rig. Had to totally discharge the one battery using a fixed load headlamp. Only once stone dead could I put it on a battery charger and straighten out the polarity.

 

[lmuss53]

Does the radio work?

If you are serious about a disgruntled neighbor keep in mind that this would involve the person being able to spend a few hours behind your boat doing some pretty extensive disassembly and rewiring.

The only way for the starter to spin backwards is if the polarity is reversed, it may be impossible, but trust me it has happened.

 

[Silvertip]

The motor is not turning backwards. Why??? Because the Bendix would not engage the flywheel if it was!!

 

[hpnme]

Red lead from meter to positive terminal on battery and black lead to negative terminal 11.29 vdc. Continuity check from positive terminal to red starter motor connection on motor 0.....to motor ground infinity. Same check from negative terminal to motor ground 0......positive terminal infinity.

​How do I post pictures?

The starter motor is turning backwards. Why Because the Bendix does not engage the flywheel. That is my problem. When I turn the starter motor clockwise by hand the Bendix does lift to engage. When I spin it counterclockwise by hand it does not lift.

I don't have a radio.

 

[sam am I]

Perhaps it's starter is in fact cranking in the proper direction BUT, when it fires, it reverses!!

Story time!!!

I recall in my model airplane days, the "cox .049" engines etc (although reedless 2 strokes) that you'd have to hand/finger start (unless you have once of those fancy manual electric rotation thingies that spun it for you) could sometimes jump into running backwards although you were spinning them forwards when starting them.

I recall this quite vividly because when it happened, I was like WTH and my dad said it happened sometimes and just throw a rag into the prop to stop it and try again........

End Story...

Back to the merc and timing, I'd think before TDC should become after TDC if it used a trigger setup but it would still run, poorly, but it'd still run. Now, I'f it were points however, I'd think it'd run quite happy in reverse as points would run symmetrically either way.

I guess IF it's actually doing this, runnign backwards after the starter was turing forwards that is, I'd be asking why now? Perhaps a particularly specific type of failure or wear or mouse in the engine or something has occurred and is allowing this ...IDK. If my motor did this, I'd be a bit perplexed but since my airplane's ran backwards, I wouldn't claim Aliens are involved......not yet anyway.

Just my .02

 

[flyingscott]

Make a video of your motor turning with the starter and put it up. A pic is worth a 1000 words

 

[Silvertip]

Physics 101!!!!! Starter must turn counter clockwise to make engine turn clockwise. If it was a belt and pulley arrangement then both would turn same direction.

 

[sam am I]

Ooops, I jumped ahead, I thought it actually had started and the engine's rotation reversed....geeesh, nevermind. I missed something, not the first time.

Yes, Silver is correct, if the OP is just cranking it and seeing the two gears running each other.....This shouldn't be a mystery, should it?

 

[racerone]

????---You say the starter is turning---COUNTERCLOCKWISE-------Well that is correct for turning / starting the motor running in the ---CLOCKWISE----direction.---Please review what you have written and understand on this situation !!---Please review your understanding of how the bendix rises to engage the flywheel !!----Try this , hold the pinion gear steady.---Now turn the starter armature with a wrench in a counterclockwise direction.----What do you observe ?