Grinding Gears

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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Sun Feb 04, 2018 12:52 pm

muleman7 wrote:
Sun Feb 04, 2018 8:23 am
2nd and 3rd is synchronized and is able to handle the shift while the mule is moving. So if the clutch is not fully releasing you will still be able to shift.
Thanks,
Butch
1952 USMC M38A1
1968 USMC M274A5

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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Thu Feb 08, 2018 4:03 pm

m38a1butch wrote:
Sun Feb 04, 2018 6:46 am
muleman7 wrote:
Sat Feb 03, 2018 7:43 pm
m38a1butch wrote:
Sat Feb 03, 2018 11:32 am


Yes and it does shift into 1st & R with no problem.
I would check the clutch disk, pressure plate, throwout bearing and sleeve before tearing into the transmission. My guess is the clutch disk is dragging when the clutch pedal is fully depressed.

Unable to shift into 1st-rev with the engine running and clutch fully depressed is a cause of:

1-clutch disc spinning while the clutch is fully depressed
2-not coming to a complete stop prior to shifting

Clutch free play before throwout bearing contacts pressure plate should be 1/2"

1-top bar of foot basket bent inward not allowing full movement of clutch pedal [likely] push in clutch and pull up on clutch cable then try shifting
2-clutch pedal adjustment not correct too much free play [likely]
3-clutch disc fingers warped causing the linings to be too wide dragging on the flywheel and pressure plate [not as likely]
4-levers or fingers on pressure plate not properly adjusted [seldom the problem]
Thanks -- I too don't want to go into the transmission as my first choice. So it looks like I'll be pulling the engine to check out the clutch system. I have one nagging question though, if it is the clutch then wouldn't it also grind gears in 2nd & 3rd? Since I'm a new mule owner there's much I don't know but with guys like yourself I'll get there (if I don't die of old age first :mrgreen: )
I pulled the engine and this is what I found:
Retainer spring was not attached to the throw out bearing retainer
Retainer was ALL chewed up
Yoke was pretty worn on the tips
I see I have oil in the bottom of the housing which indicates a bad axle seal but that's a repair for another time.
Fingers on pressure plate was severely gouged just below the finger tips (I always thought the throw out bearing contacted the raised portion on the end of the fingers so this was a big surprise to me). If the bearing is not supposed to touch the fingers where it shows then I have no clue how this happened. As of yet I haven't pulled the pressure plate and disc but will do so. Regardless I ordered the parts from John Emery to replace the entire clutch system.
Here are some pictures
Image
Image
Image
Image
Image
1952 USMC M38A1
1968 USMC M274A5

muleman7
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Re: Grinding Gears

Post by muleman7 » Thu Feb 08, 2018 6:16 pm

It appears that the throwout bearing failed and the back side worked back wearing the carrier fingers then the bearing froze and wore the levers on the pressure plate. You may re-use the pressure plate as the tips are not worn where the throwout bearing makes initial contact.

Best practice is replace the pressure plate, clutch disc, carrier and throwout bearing. Pressure plate and clutch disc may be reused but that is your choice. You only want to do this once.

There is a small spring that attaches to the throwout bearing carrier and input shaft cover that pulls the carrier back against the cover.
Mules are my passion
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Re: Grinding Gears

Post by m38a1butch » Sun Feb 25, 2018 10:35 am

muleman7 wrote:
Thu Feb 08, 2018 6:16 pm
It appears that the throwout bearing failed and the back side worked back wearing the carrier fingers then the bearing froze and wore the levers on the pressure plate. You may re-use the pressure plate as the tips are not worn where the throwout bearing makes initial contact.

Best practice is replace the pressure plate, clutch disc, carrier and throwout bearing. Pressure plate and clutch disc may be reused but that is your choice. You only want to do this once.

There is a small spring that attaches to the throwout bearing carrier and input shaft cover that pulls the carrier back against the cover.
After analyzing this I've come to the conclusion that who ever installed the clutch system prior to me obtaining the mule installed the throw out bearing in backwards causing the backside of the bearing to slide down the pressure plate fingers causing the deep gouges in each of the fingers. It's been my experience that the "flat" side of the throw out bearing always contacted the finger tips of the pressure plate.
1952 USMC M38A1
1968 USMC M274A5

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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Sun Feb 25, 2018 2:49 pm

m38a1butch wrote:
Sun Feb 25, 2018 10:35 am
muleman7 wrote:
Thu Feb 08, 2018 6:16 pm
It appears that the throwout bearing failed and the back side worked back wearing the carrier fingers then the bearing froze and wore the levers on the pressure plate. You may re-use the pressure plate as the tips are not worn where the throwout bearing makes initial contact.

Best practice is replace the pressure plate, clutch disc, carrier and throwout bearing. Pressure plate and clutch disc may be reused but that is your choice. You only want to do this once.

There is a small spring that attaches to the throwout bearing carrier and input shaft cover that pulls the carrier back against the cover.
After analyzing this I've come to the conclusion that who ever installed the clutch system prior to me obtaining the mule installed the throw out bearing in backwards causing the backside of the bearing to slide down the pressure plate fingers causing the deep gouges in each of the fingers. It's been my experience that the "flat" side of the throw out bearing always contacted the finger tips of the pressure plate. The picture is the exact way it looked when I removed the engine. The throw out bearing retainer is almost completely worn through.
Image
Image
1952 USMC M38A1
1968 USMC M274A5


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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Thu Mar 01, 2018 12:40 pm

Okay, I replaced the throw-out bearing, retainer, retainer spring (pressure place/clutch disc was good), put the engine back in. Started up fine took it for a drive, all gears shifted fine then all of the sudden it would shift in all gears but nothing happened, like it was in neutral. Put mule in neutral and I could hear gears that weren't exactly grinding but almost like gears that were barely rubbing against each other. Any ideas what's going on?
1952 USMC M38A1
1968 USMC M274A5

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Re: Grinding Gears

Post by muleman7 » Thu Mar 01, 2018 1:51 pm

Check your L /H rang lever that it is fully engaged in either range. Sometimes the swing lever attached to the shift rod is frozen and does not allow for full movement.
Mules are my passion
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Re: Grinding Gears

Post by m38a1butch » Thu Mar 01, 2018 5:46 pm

muleman7 wrote:
Thu Mar 01, 2018 1:51 pm
Check your L /H rang lever that it is fully engaged in either range. Sometimes the swing lever attached to the shift rod is frozen and does not allow for full movement.
That was the problem. Somehow it was pushed closer to the neutral position and being a new mule owner (I feel a little like an ass here) I didn't even think to check that. Everything's fine. Clutch works like it should. Life is good.
1952 USMC M38A1
1968 USMC M274A5

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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Thu Mar 01, 2018 5:52 pm

m38a1butch wrote:
Thu Mar 01, 2018 5:46 pm
muleman7 wrote:
Thu Mar 01, 2018 1:51 pm
Check your L /H rang lever that it is fully engaged in either range. Sometimes the swing lever attached to the shift rod is frozen and does not allow for full movement.
That was the problem. Somehow it was pushed closer to the neutral position and being a new mule owner (I feel a little like an ass here) I didn't even think to check that. Everything's fine. Clutch works like it should. Life is good.
Image
Image
1952 USMC M38A1
1968 USMC M274A5

muleman7
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Posts: 486
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Re: Grinding Gears

Post by muleman7 » Thu Mar 01, 2018 7:24 pm

Do not feel bad and the only dumb question is the one NOT ASKED. The Mule, as with any vehicle, takes time to learn its characteristics. For daily driving on dirt I keep 4 #s of tire pressure. If hauling a load then up to 12 #s is recommended. I only run tires with tubes the 7.50 x 10 and 26 x 1200 x 12. The lower tire pressure gives a smother ride if there is such. High speed on rough ground will beat out your teeth.
Mules are my passion
www.m274armymules.com

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