Slow rotating starter 78' Johnson:

Jayb123

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Hey all....
I was wondering if anyone might have an idea why my starter is rotating too slow to start the motor. Seems as if the motor turns over better with plugs out ......and it spins like a champ when not engaged to the flywheel The wires also seem to be very warm to the touch. I jumped the starter from my car battery. I am pretty sure the ground is good and the battery from my car is good. So what gives?

I have this evening taken apart my starter to clean it out and inspect it. Did some cleaning etc.... I will try it tomorrow and update.

Thanks for the help :D
 

Daviet

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Re: Slow rotating starter 78' Johnson:

Sounds like your starter needs some TLC.
 

wilde1j

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Re: Slow rotating starter 78' Johnson:

The wire getting hot should tell you something. (High resistance causes hot wires). Most slow startewrs are caused by corroded wiring, bad terminations, etc. Try jumping around the solenoid to eliminate that as as possible cause, but I'll put my money on wiring/terminations. Voltage drop measurement would confirm this.
 

samo_ott

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Re: Slow rotating starter 78' Johnson:

If the wires are warm there's probably some resistance somewhere. Remove all heavy gauge wires and clean n connections well and try again. Also try using jumoer cables directly to the starter to bypass all the wiring to see if it works then. If so it's the wiring, if not it's the starter.
 

Jayb123

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Re: Slow rotating starter 78' Johnson:

After reading some threads.... its ok to put a little grease on the top and bottom of the spindle of the starter but none inside correct?
 

Daviet

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Re: Slow rotating starter 78' Johnson:

Yes, very little grease.
 

Jayb123

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Re: Slow rotating starter 78' Johnson:

Update.... I give up. I cleaned out the starter.. got the inside with some sandpaper. put a lil grease on the spindle. It spins at the same speed. Not sure whats going on... and the wires keep getting hot. Resistance from where though. I have bypassed the solenoid and have jumped it straight to the starter from the battery.
 

JB

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Re: Slow rotating starter 78' Johnson:

You didn't do the easiest part, Jay. Take both battery cables off at both ends. Scrub them shiny and reconnect.

Let us know what happens, and good luck. :)
 

samo_ott

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Re: Slow rotating starter 78' Johnson:

If you have done everything including jumping it right to the starter, then I would recommend taking it to a starter/generator shop for proper load testing.
 

bob johnson

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Re: Slow rotating starter 78' Johnson:

Id buy some short battery cables add some terminals, and charge your battery and set it near the motor and hook it up... if the motor starts now, then you had some seriously corroded battery cables( inside where you cant see!!)

if the cables still get hot and or you cant turn the starter over very fast, then Id say the trouble is the starter most likely..

you could also have some drag on the crank and pistons....

with the plugs out can you turn the motor over by hand???

if not, id be looking into mechanical problems in the crank-pistonsd assembly


good luck

bob
 

clemsonfor

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Re: Slow rotating starter 78' Johnson:

You didn't do the easiest part, Jay. Take both battery cables off at both ends. Scrub them shiny and reconnect.

Let us know what happens, and good luck. :)

This would be good to do but if he hooked his cables directly to the starter and it was still slow this wont help a thing as its the starter. He eliminated this as a problem.
 

Jayb123

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Re: Slow rotating starter 78' Johnson:

WOOHOO...
I want to thank everyone for thier help and support and especially JB. After reading his post I went outside literally and took a wire wheel to the ends of the wires (I didnt know they were copper btw :facepalm:). Then it struck me...I needed the best possible contact. I removed the jumper cables from the equation (since I was jumping from my car battery) and connected my cables directly to the battery itself the ground to my OB block and the touched the Positive to the starter and rooma-zoom-zoom. Turned over perfectly... the motor took some coaxing but I finally got it running.
 

clemsonfor

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Re: Slow rotating starter 78' Johnson:

I dont see how this worked, If you were jumping with the hot wire from jumper cables hooked to the starter then grounding the other one on the block and it was still turning slowly with the jumper wires than the CABLE ends have nothing to do with the current flowing to your starter as its all in the jumper wires and the boat wires are not in the equation.

But glad you got it!
 

bob johnson

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Re: Slow rotating starter 78' Johnson:

I think he was just getting a poor connection from the jumper cables, as well asa poor connection through the battery cable terminals

bob
 

JB

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Re: Slow rotating starter 78' Johnson:

This would be good to do but if he hooked his cables directly to the starter and it was still slow this wont help a thing as its the starter. He eliminated this as a problem.

I would wager that he did not jump the battery ground directly to the starter. That is where 90% of corrosion happens, where there is a tin plated copper tab bolted with steel bolt to an alloy block. Really needs to be serviced at least annually, yet everyone ignores it, buys solenoids, starters and batteries. . . . .then fixes the real trouble.
 

Jayb123

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Re: Slow rotating starter 78' Johnson:

I would wager that he did not jump the battery ground directly to the starter......

You are correct JB.. I was clipping the ground (black) wire from the jumper cables onto the block of the OB...same location the marine cable ground is bolted.... but not the starter itself. I did however touch/jump the (red) wire onto the starter post of the starter itself. I think the solution to the equation was:

1. Cleaning the cable ends.
2. Removing the jumper cables totally which were of a smaller gauge.

Either way thanks again guys :D

(now back to working on the boat)
 
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