Grinding Gears

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m38a1butch
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Grinding Gears

Post by m38a1butch » Thu Feb 01, 2018 2:10 pm

I recently obtained an A5 which I'm very happy with EXCEPT
It grinds gears in 1st and reverse.
I've tried shifting into 2nd first but that didn't help.
The front clutch cable is run all the way into the clevis.
I attached a brake cable adjuster and it still grinds.
Even if the long clutch cable was stretched a little over the years the cable adjuster should compensate for that.
Sooo, I'm at a loss as to where to go next.

Any ideas?
USMC 1959 - 63
--------------------------
1952 USMC M38A1 MD delivered 9/52
1952 1/4 Ton M100 trailer delivered 9/52
1968 USMC M274A5 (now resides in the National Vietnam War Museum in Weatherford, TX -- RIP Francis)


markrdje
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Re: Grinding Gears

Post by markrdje » Thu Feb 01, 2018 2:38 pm

I'd check the gear oil level in the transmission, maybe clutch adjustment, but maybe you already did this
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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Thu Feb 01, 2018 2:50 pm

markrdje wrote:
Thu Feb 01, 2018 2:38 pm
I'd check the gear oil level in the transmission, maybe clutch adjustment, but maybe you already did this
Thanks, I've checked the fluid levels.
When you say clutch adjustement, is there any other clutch adjustment to be made other than adjusting the cable?
USMC 1959 - 63
--------------------------
1952 USMC M38A1 MD delivered 9/52
1952 1/4 Ton M100 trailer delivered 9/52
1968 USMC M274A5 (now resides in the National Vietnam War Museum in Weatherford, TX -- RIP Francis)

markrdje
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Re: Grinding Gears

Post by markrdje » Thu Feb 01, 2018 4:15 pm

There might be more, look in the TM, all I remember is the free play
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muleman7
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Re: Grinding Gears

Post by muleman7 » Thu Feb 01, 2018 8:02 pm

Your clutch pedal will only move the throwout bearing a measured amount and from your explanation you have taken all the slack up in the cable so you have no more fee play in your clutch pedal so you are causing your pressure plate to pull away from the flywheel to its maximum.

I would depress the clutch and the pull up on the cable to try to make the pressure plate move to its limit. If you still grind gears shifting into 1st-rev then you will have to pull the engine and check the thickness of the clutch disk.

I have seen the metal fingers warped or rusted so the linings are too wide and the clutch will not release from the pressure plate and flywheel when the clutch pedal is pushed in all the way.

I will measure the thickness of a new clutch disc and post later.

The figure below describes setting the height of the clutch levers.

Image
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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Sat Feb 03, 2018 6:09 am

muleman7 wrote:
Thu Feb 01, 2018 8:02 pm
Your clutch pedal will only move the throwout bearing a measured amount and from your explanation you have taken all the slack up in the cable so you have no more fee play in your clutch pedal so you are causing your pressure plate to pull away from the flywheel to its maximum.

I would depress the clutch and the pull up on the cable to try to make the pressure plate move to its limit. If you still grind gears shifting into 1st-rev then you will have to pull the engine and check the thickness of the clutch disk.

I have seen the metal fingers warped or rusted so the linings are too wide and the clutch will not release from the pressure plate and flywheel when the clutch pedal is pushed in all the way.

I will measure the thickness of a new clutch disc and post later.

The figure below describes setting the height of the clutch levers.

Image
Thanks for the inputs. I never thought of depressing the clutch and pulling up on the cable but it makes sense
USMC 1959 - 63
--------------------------
1952 USMC M38A1 MD delivered 9/52
1952 1/4 Ton M100 trailer delivered 9/52
1968 USMC M274A5 (now resides in the National Vietnam War Museum in Weatherford, TX -- RIP Francis)

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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Sat Feb 03, 2018 8:27 am

I can shift into 2nd & 3rd (hard to shift) and it doesn't grind gears.
1st & reverse grinds to the point I'm afraid to force it.
Seems to me that if I can get it into 2nd & 3rd and not into 1st & reverse that would indicate a transmission issue but since the mule is new to me I'm not sure.

am I looking at a transmission problem or a clutch problem?
USMC 1959 - 63
--------------------------
1952 USMC M38A1 MD delivered 9/52
1952 1/4 Ton M100 trailer delivered 9/52
1968 USMC M274A5 (now resides in the National Vietnam War Museum in Weatherford, TX -- RIP Francis)

markrdje
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Re: Grinding Gears

Post by markrdje » Sat Feb 03, 2018 8:39 am

Did you try shifting with the engine not running?
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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Sat Feb 03, 2018 9:32 am

markrdje wrote:
Sat Feb 03, 2018 8:39 am
Did you try shifting with the engine not running?
Yes and it does shift into 1st & R with no problem.
USMC 1959 - 63
--------------------------
1952 USMC M38A1 MD delivered 9/52
1952 1/4 Ton M100 trailer delivered 9/52
1968 USMC M274A5 (now resides in the National Vietnam War Museum in Weatherford, TX -- RIP Francis)

markrdje
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Re: Grinding Gears

Post by markrdje » Sat Feb 03, 2018 10:16 am

I wonder if very dirty gear oil could be part of the problem, but the muleman7 is the expert, he knows these mules.I am a novice mule owner
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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Sat Feb 03, 2018 12:01 pm

markrdje wrote:
Sat Feb 03, 2018 10:16 am
I wonder if very dirty gear oil could be part of the problem, but the muleman7 is the expert, he knows these mules.I am a novice mule owner
I've changed the transmission oil
USMC 1959 - 63
--------------------------
1952 USMC M38A1 MD delivered 9/52
1952 1/4 Ton M100 trailer delivered 9/52
1968 USMC M274A5 (now resides in the National Vietnam War Museum in Weatherford, TX -- RIP Francis)

muleman7
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Re: Grinding Gears

Post by muleman7 » Sat Feb 03, 2018 5:43 pm

m38a1butch wrote:
Sat Feb 03, 2018 9:32 am
markrdje wrote:
Sat Feb 03, 2018 8:39 am
Did you try shifting with the engine not running?
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]
Mules are my passion
www.m274armymules.com

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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Sun Feb 04, 2018 4:46 am

muleman7 wrote:
Sat Feb 03, 2018 5:43 pm
m38a1butch wrote:
Sat Feb 03, 2018 9:32 am
markrdje wrote:
Sat Feb 03, 2018 8:39 am
Did you try shifting with the engine not running?
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: )
USMC 1959 - 63
--------------------------
1952 USMC M38A1 MD delivered 9/52
1952 1/4 Ton M100 trailer delivered 9/52
1968 USMC M274A5 (now resides in the National Vietnam War Museum in Weatherford, TX -- RIP Francis)

muleman7
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Re: Grinding Gears

Post by muleman7 » Sun Feb 04, 2018 6:23 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.
Mules are my passion
www.m274armymules.com

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m38a1butch
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Re: Grinding Gears

Post by m38a1butch » Sun Feb 04, 2018 7:13 am

muleman7 wrote:
Sun Feb 04, 2018 6:23 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, that explains it.
USMC 1959 - 63
--------------------------
1952 USMC M38A1 MD delivered 9/52
1952 1/4 Ton M100 trailer delivered 9/52
1968 USMC M274A5 (now resides in the National Vietnam War Museum in Weatherford, TX -- RIP Francis)


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