Engine Interesting work around for Starting failure

DAMatson

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Ok, so I took the Starter Bendix gear assembly apart, found no problems with the hardware, other than some minor wear (expected). Parts work fine when manually advancing gears up the threads, so all appeared ok at first glance.

What I found is that while the parts are fine and lube works to allow manual lifting of gearset, centrifugal forces are unable to spin the gear assembly upward because gear assembly seems locked to base during the initial startup spin.

Some additional investigation shows that some other knowledgeable folks recommended NOT USING any wet lube on thread and bottom gear, instead using a DRY LUBE. Since the parts looked fine and I did in fact have wet lube on gearset, I cleaned off the WET LUBE and used DRY LUBE instead, and now the assembly floats-up and engages the engine flywheel gear. Success in this regard!

However, when I turned-off engine via the ignition key, the starter continued to remain engaged and turning (although I thought I observed the spring successfully forcing the bendix gear back down at one point). I have not yet replaced the Solenoid. Does this continued weirdness on behalf of the Starter help prove that the Solenoid is indeed defective, or could this be yet another facet of the Starter that might still be failing?

-David
 

bertsmobile1

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A faulty solenoid or ignition switch are the 2 most likely suspects.
Remove the power wire to the starter from the solenoid.
Turn the ignition switch to start then back t run several times.
While doing this, with your 3rd pair of hands measure both the power at the solenoid starter terminal and power at the trigger wire .

IF you get power at the starter terminal and none at the trigger then the solenoid is duff.

If you get power at the trigger terminal when the ignition switch has been turned back to run then the ignition switch is duff or the start relay is duff ( if you have one )
 

DAMatson

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Thank you bertsmobile1!

I'll give that a test tonight after work, weather permitting.
 

DAMatson

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Good morning Rivets!

Thank you for the info. I think that the Dry Lube was the key in resolving the failure of the Bendix to "lift-off" based on the centrifugal forces involved.

I appreciate your suggestions!

-David
 

DAMatson

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Greetings Boobala!

I'm most appreciative of the links you provided. Very helpful in determining what parts I need to get. Thank you!

-David
 

Boobala

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Greetings Boobala!

I'm most appreciative of the links you provided. Very helpful in determining what parts I need to get. Thank you!

-David

Just trying to help a fella in a pickle" .... Good Luck .. and keep us posted !
 

DAMatson

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Hello Bertsmobile1!
Remove the power wire to the starter from the solenoid.
Turn the ignition switch to start then back to run several times.
While doing this, with your 3rd pair of hands measure both the power at the solenoid starter terminal and power at the trigger wire .

  • IF you get power at the starter terminal and none at the trigger then the solenoid is duff.
  • IF you get power at the trigger terminal when the ignition switch has been turned back to run then the ignition switch is duff or the start relay is duff (if you have one)

MTD Solenoid.jpg
Here's my Solenoid and I've labeled it based on my observations of the electrical wiring.

I'm confused by the readings that I'm getting. Either I'm doing it wrong (most likely), or the solenoid is defective (also a valid possibility).

So I've set my basic voltmeter to DCV, measured the battery from ground strap at solenoid and positive terminal on solenoid ("red from battery") and see 12v. This confirms what I would expect to see on other tests.

Then I tried taking a reading from ground strap from battery and the other big terminal going from the solenoid to the starter and saw nothing when twisting key from run to start several times.
Then I tried taking a reading from ground strap from battery and the small terminal going to the ignition switch (I presume this is what you meant by trigger terminal?) and saw nothing when twisting key from run to start several times.

Am I testing this correctly?
 

Boobala

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Hello Bertsmobile1!


View attachment 36523
Here's my Solenoid and I've labeled it based on my observations of the electrical wiring.

I'm confused by the readings that I'm getting. Either I'm doing it wrong (most likely), or the solenoid is defective (also a valid possibility).

So I've set my basic voltmeter to DCV, measured the battery from ground strap at solenoid and positive terminal on solenoid ("red from battery") and see 12v. This confirms what I would expect to see on other tests.

Then I tried taking a reading from ground strap from battery and the other big terminal going from the solenoid to the starter and saw nothing when twisting key from run to start several times.
Then I tried taking a reading from ground strap from battery and the small terminal going to the ignition switch (I presume this is what you meant by trigger terminal?) and saw nothing when twisting key from run to start several times.

Am I testing this correctly?

SORRY for "buttin -in" Bert, YES your test is right, to prove the solenoid is bad take a cable (same size wire as BIG solenoid cables, and jumper from battery side of solenoid to starter side of solenoid ( connecting the 2 big posts in essence ) if starter spins, then, as bert says the solenoid is "duff" ( no good) then try connecting battery side of solenoid to the starter terminal, only other thing to check is the ignition switch (power from BATTERY terminal to Starter terminal ( key in start position)
 
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BlazNT

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SORRY for "buttin -in" Bert, YES your test is right, to prove the solenoid is bad take a cable (same size wire as BIG solenoid cables, and jumper from battery side of solenoid to starter side of solenoid ( connecting the 2 big posts in essence ) if starter spins, then, as bert says the solenoid is "duff" ( no good) then try connecting battery side of solenoid to the starter terminal, only other thing to check is the ignition switch (power from BATTERY terminal to Starter terminal ( key in start position)

I am butting in Boo and too bad for you.:laughing::laughing: He said he had no voltage to the trigger wire from the key switch. I am guessing a bad switch at least if not the solenoid too.
 

DAMatson

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I am butting in Boo and too bad for you.:laughing::laughing: He said he had no voltage to the trigger wire from the key switch. I am guessing a bad switch at least if not the solenoid too.

Hello BlazNT!

I apologize, I have neglected to mention that I had already tested the ignition switch and came to the conclusion that it was good. I tested it by checking for continuity between the S (Starter Solenoid) pin and the B (Battery) pin, more specifically, I saw that continuity while the switch was in START position, but it went away when in RUN and OFF postions.

MTD Ignition Switch.jpg

This is part of my confusion in the second set of results that I posted above. I feel like I should have gotten a 12v reading on that, which is why I'm so stumped...

-David
 
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