Disassembling my M20 and need some help.

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Jul 3, 2005 | 10:41 PM

ImBatman

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From: Lake Wylie, South Carolina

Disassembling my M20 and need some help.

I am waiting for my rebuild kit and the rebuild video to come from 5speeds.com but I got impatient and started tearing it down this weekend. Everything has come apart pretty easy especially since I went and bought a decent pair of lock ring pliers. Anyway here is where I am stuck at. How do you get the threaded collar unscrewed that holds the input shaft into the front of the case? I have soaked it in penetrating oil but cannot break it loose. I am sure that there is a specialty tool for this but I have been using a set of vise grips to hold the input spline and then put a pipe wrench on the collar. Also from what it looks like the threads on the shaft are left hand so the collar should come off turning it to the right or in other words the opposite of the old righty tighty method correct?

Thanks

Jul 4, 2005 | 12:19 AM

427Hotrod

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Yes it is left hand thread.

Do you have it all apart otherwise? Often you can stick a red rag in there and rotate trans until it locks up with the rag wedged between the gears.

You can put in tow gears at once to lock it up.

You can take a hammer and punch (most likely will work best) to tap it loose. Usually just takes a little persuasion to get it loose.

Good luck!

JIM

Jul 4, 2005 | 01:31 AM

stingr69

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From: Little Rock AR

Is it staked to the input shaft? I seem to remember that nut needs to be lightly tightened during assembly or it stresses the front bearing.

Second thought, it has been maybe 20 years since I completely tore down and rebuilt a Muncie so maybe you should wait for better instructions.

-Mark.

Jul 4, 2005 | 07:55 AM

StickShiftCorvette

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I just made a "custom" spanner wrench out of piece of steel and welded a nut to allow proper torquing of the nut when reassembling.

Jul 4, 2005 | 10:57 AM

ImBatman

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From: Lake Wylie, South Carolina

Thanks for the ideas guys. I have the main shaft of gears out but the smaller shaft that rotates on the press in shaft are stilll there so I should be able to lock the gears up with a rag as Jim suggested. I will keep you updated.

Thanks again!

Wade

Jul 4, 2005 | 03:27 PM

Solid LT1

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From: Fremont CA

Use a pipe wrench on that sucker! Your biggest problem I suspect is that you don't realize it is a "reverse" thread so its clockwise to loosen the retainer nut (this was done so that the torque load would tend to keep the nut tight over it's service life.) I would also "stake" the new nut with a punch when you finish the rebuild of your Muncie. One last tip, use 3M wheather strip adhesive on you countershaft to main case to seal it up, it has worked well for me over the years to prevent leaks.

Jul 5, 2005 | 09:02 AM

jimbow

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From: Lincolnton NC

Ken Hanlin at K & C Trans., Cherryville, NC (about 30-40 miles) knows and can help on Muncies. 704-435-6827

autogear.com ......they mfg Muncie parts....have good Muncie site, try them.

In Charlotte, try Dub, Corvettes Etc., 704-394-5150, 4927 Wilkinson Blvd. (have used him, he's good but expensive..willing to share)

Juniors transmission, in Belmont (never used, but reputed to be a Muncie expert) 704-827-5203

Hows that?

good luck, jim

Jul 5, 2005 | 10:06 AM

ImBatman

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From: Lake Wylie, South Carolina

Well the trannie is disassembled. All the gears look good, no missing or broken teeth. Syncro's were in fair condition but did show some wear. there was a good bit of what looks to be graphite in the case. I have been told that this was an old trick to help quiet noise from a failing tranny.

Hopefully the new tranie kit and video will be in in a day or so. The job doesn't look to intimidating although I am scared to death of all those little needle bearings

They pretty much all fell out so I can't wait to look at the how to video to see how you get these things back in.

Anymore words of wisdom, tips,tricks etc?

Thanks
Wade