Transmission install..

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nodemon

nodemon

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First time installing a transmission.. I'm installing a 4spd in my small block 72 Demon.. I've got it close, just can't get it to "seat" and I don't want to force it...but damn, I feel like I'm so close.. All bolt holes are lined up and started. Any tips..??
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Im not a four speed guy, but if the input shaft doesnt fit the crank, thats one possibility.
 
It looks like your threaded studs are too long maybe causing a little interference
 
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Did you have this trans bolted to this Bell previously
 
Put the clutch fork and linkage in. Have someone release the pressure plate. Input shaft can be bound up a bit on the disc.
 
Professor Fate said:
You DID confirm that your crank pocket was machined to full depth before going this far, right?
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No...I didn't confirm anything, but a buddy of mine said the engine, when I was buying it, was set up for the manual trans. He made it a point to look.. but I thought he just checked for the "hole".. I didn't know they could be machines at certain depth..
 
Did you take it off the Trans Jack and try to slide it on the studs the rest of the way?
 
I don't remember, do small blocks suffer the fate of shallow pilot holes like B/RB do? Be careful and do not force it. Make sure the clutch disc is not reversed

You can MEASURE the depth. Rig a depth gauge with a straightedge and "anything" you can mark, a rod, dowel, piece of allthread with a nut, etc, then compare to the transmission
 
And you test fitted the trans. bearing retainer to the bellhousing recess to confirm they are a match?
Either a shallow crank pocket or a mismatched bearing retainer/bellhousing could each get you hung up in that approximate spot.
 
Professor Fate said:
And you test fitted the trans. bearing retainer to the bellhousing recess to confirm they are a match?
Either a shallow crank pocket or a mismatched bearing retainer/bellhousing could each get you hung up in that approximate spot.
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Professor Fate said:
And you test fitted the trans. bearing retainer to the bellhousing recess to confirm they are a match?
Either a shallow crank pocket or a mismatched bearing retainer/bellhousing could each get you hung up in that approximate spot.
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Bellhousing came with and was attached to trans when I bought it.
 
nodemon said:
Bellhousing came with and was attached to trans when I bought it.
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Right.... i would have confirmed without the clutch at all to start....and then confirmed the clutch pieces fit in the bell before attempting assembly..... it just eliminates at lot of variables up front.
 
Lefty71 said:
Right.... i would have confirmed without the clutch at all to start....and then confirmed the clutch pieces fit in the bell before attempting assembly..... it just eliminates at lot of variables up front.
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Unfortunately, I'm just winging things as I didn't realize there could be issues... Just thought if engine was set up for manual, I was good to go...
 
nodemon said:
No...I didn't confirm anything, but a buddy of mine said the engine, when I was buying it, was set up for the manual trans. He made it a point to look.. but I thought he just checked for the "hole".. I didn't know they could be machines at certain depth..
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Some engines that were originally paired with an automatic transmission may not have the pilot hole fullly machined.
Do you have a pilot bushing, or the roller bearing that fits into the convertor recess? It could have had the roller bearing pressed in and appear to be "stick ready", but not have the pilot hole fully machined and your input shaft is bottoming out in the crank. You really need to check the depth as @67Dart273 outlined above.
Hopefully, all you're experiencing is a little stubbornness of the splines and pilot to mesh together. They can be finicky sometimes, keep at it. Sometimes it helps to have the trans in gear, and put in the driveshaft yoke so you can jiggle things around a bit as you try to slide the trans in.
 
Professor Fate said:
Some engines that were originally paired with an automatic transmission may not have the pilot hole fullly machined.
Do you have a pilot bushing, or the roller bearing that fits into the convertor recess? It could have had the roller bearing pressed in and appear to be "stick ready", but not have the pilot hole fully machined and your input shaft is bottoming out in the crank. You really need to check the depth as @67Dart273 outlined above.
Hopefully, all you're experiencing is a little stubbornness of the splines and pilot to mesh together. They can be finicky sometimes, keep at it.
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So, I gingerly tightened the bolts, going back n forth, side to side with a small box wrench... It pulled in with no resistance... Not sure if that means everything is good, but it went in "easily" ...
 
nodemon said:
So, I gingerly tightened the bolts, going back n forth, side to side with a small box wrench... It pulled in with no resistance... Not sure if that means everything is good, but it went in "easily" ...
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Mine does the same thing. Pretty sure it's just a tight fitting pilot bearing. I am going to take a thousands or two from the inside of the pilot bearing on the lathe before I install it in the Hemi crank. I don't ever remember having these issues when I was 20!
 
Sometimes, what you did is what you need to do to get that transmission to seat, as long as you tighten the bolts slowly & on the diagonal. If ANY resistance is felt, STOP. Be sure to double check everything next time before the transmission goes in, don't take someone's word for it, they could be wrong. Those things are HEAVY, especially doing it on your back.
P.S. Make sure the clutch alignment tool (Splined like your input shaft & usually supplied with the new clutch kit) slides in & out of the installed clutch easily to be sure the clutch disc is perfectly lined up. That helps a lot too.
 

niceolddart said:
Sometimes, what you did is what you need to do to get that transmission to seat, as long as you tighten the bolts slowly & on the diagonal. If ANY resistance is felt, STOP. Be sure to double check everything next time before the transmission goes in, don't take someone's word for it, they could be wrong. Those things are HEAVY, especially doing it on your back.
P.S. Make sure the clutch alignment tool (Splined like your input shaft & usually supplied with the new clutch kit) slides in & out of the installed clutch easily to be sure the clutch disc is perfectly lined up. That helps a lot too.
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Good to hear that what I did isn't unheard of...
It was about 3 years ago when I installed clutch, etc... but I used the alignment tool at that time..and did confirm with that tool before I installed the tranny that it slid in and out with no issues. I guess time will reveal whether or not everything is ok..
Almost 4 years with this project and all I want to do is finally drive it.. My first and last project, that's for sure...!
 
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