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peterdee

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Discussion starter · #1 ·
we have an MTD Cub Cadet with Command OHV 16 engine fitted with Kohler 25 098 08 starter motor.Suddenly refused to start, starter not engaging with the fly wheel. dismounted starter and checked performance; running lazily. Checked wiring, A OK, fitted slave solenoid. Starter now runs fine but still does not engage with fly wheel.
There was a thread on here in 2005 about this problem with the Kohler starter, and Kohler's refusal to recognise the fact, apart from publishing an alternate wiring diagram to prevent the starter motor running on. What was not discussed was a solution to the situation. Is there a solution? I'm thinking of touching up the teeth on the starter dog; doing the same to the fly wheel, machining the fly wheel and rotating it?? But they don't seem badly damaged. With this starter motor doing what it is supposed to do, apart from engaging, I can't see any benefit in fitting a new starter.
Any thoughts from you guys out there would be appreciated.
 
#2 ·
Can you perform a test ?

Put a multimeter black lead to ground and red lead on the small solenoid activation wire, Turn the key and post the voltage on this wire while trying to crank.....
 
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#4 ·
John Deere for one of a couple other equipment makers had starter engagement problems, They came out with a starter relay kit that solved the issue.

You can install a relay which would give the solenoid full battery voltage (12.6), That should cause the bendix drive gear to engage the flywheel ring gear harder.

You can pick up a 30 amp relay at any auto parts store and wire as below and see if that solves your issue, I've done it on a few machines...... Mount the relay to the frame near the starter......

 
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#6 ·
Resistance in wiring/switches and connections can rise over time......It's quicker/easier and less cost to add a relay to see if that solves the issue rather than replacing a starter/harness or any switches......
 
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Discussion starter · #7 ·
I've put in a slave relay, which is essentially the same thing as a relay. The wiring is the same. That has not cured the problem. I wonder if the resistance lies in the braided wire between the starter solenoid and the motor?
 
#8 ·
I need the full engine model AND spec numbers to go any further at this point.....
 
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Discussion starter · #9 ·
when I said slave relay, I meant slave solenoid! I'm not sure where the engine no is? I guess on the carburetor side of the engine, but everything is covered up; don't want to take the whole machine apart! I have lots of other numbers relating to MTD but I guess the key is the engine no.
 
#10 · (Edited)
OK, I see your in England so lets get on the same page here.....


You have a 25 098 08 solenoid shift starter, Did you replace the solenoid on the starter it's self ?

Or did you just add a "slave" solenoid wired to the solenoid on the starter ?

Does the starter spin but just not engage the flywheel ?

BTW, There's only three plastic wing nuts holding the side panels on and you don't even have to fully remove them to get the panel off.......
 
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Discussion starter · #11 ·
added slave solenoid in case there was a problem with the high amperage connection in original solenoid.

the starter spins and hits the the flywheel with a good clunck.

the side panel is easy. It is the panels for the air cooling that cover where I think the engine # is that seem to need some extensive dismantling. That's why I would like to know where to go looking for the engine #.

When the starter is unmounted and just lying on the wheel, it should leap as it is energised. It doesn't. That must mean that there is a voltage loss somewhere? I still suspect the braided cable between the solenoid and the motor.
 
#13 ·
peterdee said:
When the starter is unmounted and just lying on the wheel, it should leap as it is energised. It doesn't. That must mean that there is a voltage loss somewhere?
Click to expand...
With that ^^^^^^^^ and the fact it clunks into the flywheel, Sounds like the issue is within the starter it's self. A tear-down inspection is needed checking the brush and brush lead condition/rotor windings and bushing condition, Also check the plastic engagement fork for wear.

If all looks/checks good, Clean- lube and reassemble then replace the starter mounted solenoid. There's a plunger inside the solenoid that when power is applied the plunger lowers raising the drive assembly, At the same time it lowers it makes contact with the two large cable post on the bottom. Over time these plunger contacts burn up and cause a voltage loss to the starter motor.....
 
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Discussion starter · #14 ·
stripped down starter, again. no sign of any wear or damage. Motor only done 250 hours. There is no resistance anywhere. Possible problem with cable posts in solenoid has been by passed by installing slave solenoid.
We are talking MTD Cub Cadet Series 2000, spec PS45509BA, ser no 3133900791. Can't see engine no, but it would probably start CH16S
 
#15 ·
peterdee said:
Possible problem with cable posts in solenoid has been by passed by installing slave solenoid.
Click to expand...
Please explain how/where you wired this "slave solenoid" onto the unit.....
 
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#17 · (Edited)
OK, Do me one more test.....

Put your multimeter on the braided starter motor cable lug then post the voltage reading while trying to start.

Have you turned the engine crankshaft/flywheel by hand ?

Does the starter even try to turn the engine ?
 
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#19 ·
Another "quickie" electrical check:...Put voltmeter leads directly across the braid wire you suspect...doesn't matter which color lead...look for a voltage reading "while cranking"...should be zero or close to..If you read a voltage, then suspect wire is showing a resistance, and thus a voltage drop..starving voltage to the starter..
 
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Jeff in AL
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