Rear main and transmission replacement

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mallard
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Re: Rear main and transmission replacement

Unread post by mallard » October 17th, 2017, 10:18 am

I wasn't planning on destroying a good transmission, this one is starting to come apart. I guess it could be saved though. When I drained the oil chuncks of metal came out and the oil looks like a pound of glitter was dumped in it. If somebody wants it they are welcome to it for free. It is in south central arkansas.
1965 M151A1

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rickf
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Re: Rear main and transmission replacement

Unread post by rickf » October 17th, 2017, 3:42 pm

If it is grenaded then that is a different story. It could still be repaired but they are still out there at reasonable prices. If you knock out the shaft for the countershaft then that will drop to the bottom of the case and you can remove the input shaft. You will have to check the manual for the countershaft remover procedure, it has been too long since I did one.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

mallard
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Re: Rear main and transmission replacement

Unread post by mallard » October 17th, 2017, 4:07 pm

the last clutch I changed was on a 327 and just centered the clutch disk on the pressure plate by feeling the distance from the edge. Is this an okay way to do this on here?
1965 M151A1

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m3a1
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Re: Rear main and transmission replacement

Unread post by m3a1 » October 17th, 2017, 4:39 pm

Last one we did we simply left the pressure plate fasteners a little loose which allowed the disk to slide around just a tad. We then just tickled the clutch disk a little and everything went together without any dramas and we just torqued the pressure plate fasteners down afterwards. We did this with the vehicle on a lift, which made the business of torquing everything down quite easy.

IMHO, centering it on the pressure plate does not assure that everything will fine up.

For those of you scrapping ruined transmissions, you might consider keeping the shaft as a guide just for projects such as this.

Cheers,
TJ

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rickf
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Re: Rear main and transmission replacement

Unread post by rickf » October 17th, 2017, 4:41 pm

The idea is to center the disc hole with the transmission pilot so yes, if you think you can do it that way. I would buy or borrow a universal clutch pilot tool if you don't want to do the extension and tape trick. You can also leave the pressure plate loose enough for the disc to be able to be moved and then male some guide rods out of long bolts with the heads cut off and screw them into the bell housing. Slide the transmission over the guides and carefully slide it into the disc and then move it around very gently as needed to line up the pilot. Once in take two of the guides out and put bolts in and then the other two. This sounds easier than it is and take finesse and patience. That transmiaaion does not lend itdelf to finesse due to it's shape and weight.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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rickf
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Re: Rear main and transmission replacement

Unread post by rickf » October 17th, 2017, 4:42 pm

Beat me to the loose disc trick.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

mallard
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Re: Rear main and transmission replacement

Unread post by mallard » October 18th, 2017, 11:21 pm

Thanks everyone for all the help, I got everything put together and the motor put in and hooked up tonight and the clutch and transmission work great.

I did run into a new issue that I believe is going to be a stuck float.

I am not using a stock fuel pump, I have an inline 24v fuel pump with a regulator set to 4.5 lbs. after my test drive I pulled back into the garage and let it idle. After a minute it died and wouldn't restart. I pulled the intake hose and it had gas in it. I then just turned the ignition on and gas started running out of the carb. It's never done this in the past but it has been sitting for close to a year now. Does this sound like a stick float? Thanks for all the help, feel like I'm real close to be going again.
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rickf
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Re: Rear main and transmission replacement

Unread post by rickf » October 19th, 2017, 9:13 am

If the gas is running out without the motor running then yes, a float issue. More likely something caught in the needle and seat. A stuck float will usually do just the opposite and not let any gas in. Be aware that every time the engine shuts down the accelerator pump will squirt gas out the mouth of the carb. If you crank it and it does not start then it will shoot a bit of gas out. Do not confuse this with a float issue. Have you verified the pressure at the carb with a gauge? A lot of those regulator settings are way off. 4.5 lbs. would be the most you would want. 3.5 would be better.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

mallard
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Re: Rear main and transmission replacement

Unread post by mallard » October 19th, 2017, 9:18 am

Thanks Rick, I can turn the regulator down to 3.5 and will do that tonight. This is a lot more than a squirt. With the motor off I can turn on the ignition and a gas will start running out of the carb at a slow steady trickle. Thanks again for the help.
1965 M151A1

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m3a1
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Re: Rear main and transmission replacement

Unread post by m3a1 » October 19th, 2017, 2:00 pm

Make sure you don't hydrolock that engine.

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rickf
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Re: Rear main and transmission replacement

Unread post by rickf » October 19th, 2017, 5:28 pm

Second that, If it is running out the back it is running in the manifold also and it will be possibly filling whatever cylinder has an open intake valve. Before cranking the engine again pull the plugs and with the ignition off crank it over and see if anything blows out of the cylinders. If it does it would not hurt to put a couple squirts of oil in each cylinder since they are washed dry at this point.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Mark
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Re: Rear main and transmission replacement

Unread post by Mark » October 19th, 2017, 9:19 pm

I can remember just eye balling the clutch disc to the pilot bearing while holding the PP against the disc( of course the bolts were snugged up on the plate), but you all's way sounds a lot better.Ya later on I did pick up the pilot shaft at a garage sale.
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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