4 Speed Gurus(Tailshaft removal)
#1
Race Director
Thread Starter
4 Speed Gurus(Tailshaft removal)
I need to get my speedo working again. The small gear that drives the plastic gear is out of position.
So this morning I have the car up on jack stands and the tranny mount out of the car. The 6 bolts that hold the tailshaft on are out, as is the fluid of course.
Now, I am starting to pull the tail shaft out of the tranny and some gears are coming with it. I stopped here because I don`t want to cause something that I can`t fix. Am I okay to go ahead and pull the tailshaft and just try to keep the gears in the tailshaft or try to make the gears or gear stay with the tranny. If I need I can go take some pics.
Thanks for any help.
[Modified by Eddie 70, 2:15 PM 2/15/2003]
So this morning I have the car up on jack stands and the tranny mount out of the car. The 6 bolts that hold the tailshaft on are out, as is the fluid of course.
Now, I am starting to pull the tail shaft out of the tranny and some gears are coming with it. I stopped here because I don`t want to cause something that I can`t fix. Am I okay to go ahead and pull the tailshaft and just try to keep the gears in the tailshaft or try to make the gears or gear stay with the tranny. If I need I can go take some pics.
Thanks for any help.
[Modified by Eddie 70, 2:15 PM 2/15/2003]
#2
Race Director
Re: 4 Speed Gurus(Tailshaft removal) (Eddie 70)
You are pulling the reverse gear off the shaft. What you need to do is pull the pin on the reverse shift rod. It is a small tapered pin that should push out from bottom to top. You can then slowly pull the shift rod out about 1/4 inch or so. This will disengage the shift fork from the reverse gear. Once this is done you should be able to slide the tail shaft off. You might have to twist the tail shaft one way or the other to get it off. I have always done this with the trans out which makes it easier.
#3
Re: 4 Speed Gurus(Tailshaft removal) (Gordonm)
You are pulling the reverse gear off the shaft. What you need to do is pull the pin on the reverse shift rod. It is a small tapered pin that should push out from bottom to top. You can then slowly pull the shift rod out about 1/4 inch or so. This will disengage the shift fork from the reverse gear. Once this is done you should be able to slide the tail shaft off. You might have to twist the tail shaft one way or the other to get it off. I have always done this with the trans out which makes it easier.
#4
Drifting
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Re: 4 Speed Gurus(Tailshaft removal) (Eddie 70)
Sorry I can't help, but am interested in how this turns out. My car has the same problem with the internal speedo gear. I was going to pull the trans. this winter and considered what you are trying to do as an alternative. . Please let us know. Did you get the tail off? Good luck :cheers:
#5
CFOT Attention Whore
Re: 4 Speed Gurus(Tailshaft removal) (Gordonm)
i would agree with the above proceedure but i strongly caution you pulling this apart with the trans still in the car. i'm assuming your '70 is a muncie whereas my '81 has the BW T-10. i'm not sure of the differences but in mine, the shaft the reverse idler gear rides on is actually pinned into the tail shaft housing. the idler gear is located in the main case and if the tail shaft housing is removed, gears become loose. they won't fall out of their relative location but they will fall down to a point where the shaft won't go through the gear center.
i just rebuilt mine last summer (for the second time :rolleyes: ) and ended up cutting a nice, big hole in my work bench to drop the input shaft through to stand the case vertical for just such assembly processes.
like i said, i don't know about the differences between the two transmissions but this is an area i think you need to be clear about before proceeding, or just pull the tranny. :cheers:
i just rebuilt mine last summer (for the second time :rolleyes: ) and ended up cutting a nice, big hole in my work bench to drop the input shaft through to stand the case vertical for just such assembly processes.
like i said, i don't know about the differences between the two transmissions but this is an area i think you need to be clear about before proceeding, or just pull the tranny. :cheers:
#6
Tech Contributor
Re: 4 Speed Gurus(Tailshaft removal) (Eddie 70)
Eddie Gordon has good advice. You're better off doing this on the bench. Your 70 should have a plastic gear on the main shaft unless someone changed trannies in the past. The plastic gear is held on with a clip, but the older metal gear are pressed on. You'll also have to move the housing around to engage the reverse gear, I don't know how much room you'll have with it in the car. You also have to be sure you don't damage the new gasket installing it too.
Gary
Gary
#7
Race Director
Re: 4 Speed Gurus(Tailshaft removal) (gtr1999)
The way it sounds most of the hard work is done. Just the 4 bolts now holding the case to the bellhousing and it should slide out. As long as nothing is disturbed it should slide right back in. I have done it many times and you have the hard part done. Getting it back together is going to be much easier on the bench also.
#8
Race Director
Thread Starter
Re: 4 Speed Gurus(Tailshaft removal) (Gordonm)
Well I got the tailshaft loosened enough to get to the plastic gear. It didn`t lose its retainer. :crazy: But it was just slid out of the way. Now I just need to know which way it needs to go. There is a flat spot in the shaft does it back up to this flat spot. This seems like the logical place. Just wanna make sure.
No damage to the gear either.
No damage to the gear either.
#9
Race Director
Thread Starter
Re: 4 Speed Gurus(Tailshaft removal) (Eddie 70)
A little more info here. The retainer was still in the gear and when I tried to remove it the little tit that keeps the retainer in the gear broke. So now I know what I was supposed to be looking for. What was the kicker on mine was the tit that kept the retainer in the shaft had straightened out enough to let the whole plastic gear move. Pics to follow as soon as I get back out there and take them. Maybe this will clear some of this up for others.
#11
Race Director
Thread Starter
Re: 4 Speed Gurus(Tailshaft removal) (Gordonm)
This is the 3rd gear and its idler. This is how it looks when laying under the car looking up
This is the speedo gear. The hole you see here is where the retainer goes. The retainer holds the gear in place.
This is the retainer. It is broken. There is supposed to be a little tiny clip sticking up to hold the gear on this retainer. The tit you see sticking down goes in the hole in the shaft in the above pic. The gear is held in place between the loop and the missing tit.
Gordon, Thanks for your help. You got me to this point. Now I just have to come up with a new retainer tomorrow and put it all back together.
This is the speedo gear. The hole you see here is where the retainer goes. The retainer holds the gear in place.
This is the retainer. It is broken. There is supposed to be a little tiny clip sticking up to hold the gear on this retainer. The tit you see sticking down goes in the hole in the shaft in the above pic. The gear is held in place between the loop and the missing tit.
Gordon, Thanks for your help. You got me to this point. Now I just have to come up with a new retainer tomorrow and put it all back together.
#12
Race Director
Re: 4 Speed Gurus(Tailshaft removal) (Eddie 70)
That gear is the reverse gear. That ring around the back side of the gear is what the reverse shift fork goes onto. This is going to be the only bugger when reassembling the tail shaft. My Muncie has a pressed on metal gear. Went back to some old pictures of when it was apart. You have to make sure also that big roll pin on the idler gear fits into the notch in the tail housing. It might take some wiggling but good luck with it. Good pictures.
#13
Drifting
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Re: 4 Speed Gurus(Tailshaft removal) (Eddie 70)
Those pictures are very helpful since I will be going into mine. I have the BW trans and mine shows clips holding the gear in place. My gear seems to be properly placed but I can feel mine with a finger and it seems to be slightly grooved in the middle making me think it is worn. But maybe the same problem as yours. Good luck. Let us know what happens. :cheers:
#14
Race Director
Thread Starter
Re: 4 Speed Gurus(Tailshaft removal) (R. Bruno)
I found out that the 3rd gear idler shaft has already been pulled out too far in the above picture. Bad thing. There is a thrust washer in the back that the idler shaft goes through. This thrust washer has dropped down in the pic and that is as far as the idler will go back in. I used some Vaseline to get the washer to hold its position back up while I slid the idler back in place. Pretty difficult to do but it can be done.
After bolting everything back up, all is working correctly now. Another one of those jobs I hopefully will not have to do. You will have to go to the Chevy dealer and get the clip that holds the gear in place. I went to every place in two towns and even two transmission shops. No one has the part. I finally found a friend with a tranny torn out of an old car and I borrowed his clip till I can replace his.
I hope this helps.
After bolting everything back up, all is working correctly now. Another one of those jobs I hopefully will not have to do. You will have to go to the Chevy dealer and get the clip that holds the gear in place. I went to every place in two towns and even two transmission shops. No one has the part. I finally found a friend with a tranny torn out of an old car and I borrowed his clip till I can replace his.
I hope this helps.
#15
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Re: 4 Speed Gurus(Tailshaft removal) (Eddie 70)
Thanks for the pics. and responses. I think I may just stick with the original idea to pull the trans. Gears falling out make me nervous. Congratulations on getting it done. :cheers: