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Reinsert torque conv. into trans

I have a '95 Chevy Suburban (4WD) and I’m in the process of swapping motors. The original seized up and I bought a used motor that has been rebuilt locally to replace it. I have managed to reinsert the shaft of the torque converter most of the way back into the transmission sleeve but I think the the raised keys on the shaft are not quite lined up to completely pull the two components back together. Is there some neat trick to this or do I just keep pushing and pulling with the hope that it will come together before the end of this millenium?

It’s been years since I’ve had to deal with this, but from what I recall, I pretty much just hung the torque converter on the input shaft and rotated it while pushing until it slid the rest of the way on. The input shaft doesn’t turn all that easily, so this should work well for you.

Yes, just press in lightly while rotating the torque converter clockwise and it will drop into the fully seated position.

I will just add that when you go to mate the transmission and engine together they should fit together easily and flush at the seam without being forced.
If they do not separate them and verify the converter is fully seated or there will be some major problems if you do not.

I always “pre-fill” the TC before assembling it to the trans as well. Can’t hurt and simple to do…

Thanks to all. I’m just starting the day reading your comments. I wonder if I made this unduly difficult by 1) not having a lift or even proper jack stands so the space under the vehicle is a little cramped; 2) having my attitude offset by needing to cut and use a disc grinder on one of the three bolts to remove the TC from the old engine since the head of the bolt had rounded shoulders; and 3) by trying to fit the TC while now attached to the new motor to the transmission while lying on my back. I have removed the cross-member support for the transmission so it has some vertical play as someone suggested. The first couple of inches of inserting the TC went fairly easy and I’ve seen on this shaft that there is a spline omitted from a regular pattern every 120 degrees around the narrowest shaft that makes the last inch or so much more exacting. It is physically quite an effort to work this. I’ve been using both Haynes and Chilton’s Guides for '95 Chevy engine work but surprisingly little is mentioned about torque converters. Haynes doesn’t even an entry for torque converters in the index at all. Well, here’s to a new day!

Wow, my hat’s off to you! I’ve done plenty of trans swaps in GMs with rudimentary tools and equipment in the early years but at least I had them up on jack stands! That would be a frustrating puzzle to do any assembly under the truck on the ground.

Back then I usually fit the TC to the trans and then slide it under. Found out cardboard works good for sliding it. I found out the hard way to hold the TC in position until the last moment or it had to come back down and out to get it properly seated again. Very frustrating.

Before I had two hydraulic jacks, I used the ancient Egyptian method. Lift one end a few inches and slide a board under. Lift the opposite end a few inches and insert board. Keep alternating until it’s up high enough to slide in. Only mention this for the “misery loves company” aspect.

In the “it could be worse category”, I have a Chevelle with a custom trans I built that is essentially TWO transmissions. Try lifting that beast into position!

I was fed up with a project once and decided to go over to a friend’s house to see how he was making out on a clutch job. Small FWD car, transverse engine mount. My god, he was wedged in a single car garage where you couldn’t even open one door and the other was a tight squeeze to get in the car. How he managed to do that job in those tight quarters was amazing. I was re-energized after that. My problems seemed to pale in comparison.

You’ve got the right attitude. Anyone can do it with fancy tools. You’ll have a significant sense of accomplishment when it’s all done!

To TwinTurbo,
I’ve got the front end up now on stacked RR tie blocks, stacked enough beside the wheels to lift the wheels off the ground about two inches. I’ll try the cardboard suggestion. The crew that poured the slab apparently called it a day before finishing the surface so it is devouring sweatshirts I’m wearing for padding. This trans has almost as much as you describe since it is 4WD that’s why I didn’t want to pull the trans out to fit the motor to it and then install as a combined unit. Well also because I’d need to pull the radiator and other front end parts . . . it just seemed like so much more to do than if I can just slip that shaft back in.

Sounds like you could use the cardboard under you to cut down on sweatshirt destruction! Sounds as bad on sweatshirts as roofing is to pants :wink:

I wasn’t suggesting doing the motor and trans combined, just installing the converter to the trans while the trans is out from under the truck. Makes it easier to engage the input shaft and fully seated. I’m sure you’ll get it in regardless. Good luck!

Slide the converter into the transmission FIRST, so it’s fully seated, the notches for the transmission oil pump lined up and in place…THEN mate the engine to the transmission, bolting the two units together without forcing anything…Last, bolt the torque converter to the flex-plate, the converter should spin freely to line up the bolts…

Just don’t force the TC onto the shaft. It usually can only go on one way and just slips into place without any violence.

To move heavy stuff around on plywood, I often throw some play sand under the plywood. It acts kinda like ball bearings and make moving things easier.
To lift a car way up to work under it, I usually put it on top of cribbing made from 4x4 lumber. Last summer I had one of our subies over 20" up in the air that way. The car is secure so I feel safe crawling under it.

Edit: and, should you need one, I highly recommend the HF transmission jack. That thing saved my bacon several times already.

Don’t get this one. It nearly killed me, almost dropping the transmission on my head.

No violence? What fun is that? :wink:

I remember building this sling hoist once so I could remove the body of this Corvette I was restoring, all by myself. Pretty slick set up just finished and was admiring it when a bunch of friends stopped by to drink all my beer and generally impede any progress on whatever the task at hand was. I went in to get more beers and when I came back out, they had already picked up and moved the body to its temp cribbing. :frowning:

I got to use it when I put it back on. Locked the garage doors beforehand…

Well. I dunno. I kept on with the TC already connected to the flex plate and motor. It slid together easily within 3/8 or 1/2 inch of home. The remainder pulled together with a couple of 1" ratchet straps, a little more coercion by gently turning the bolts and then raising/lowering the transmission with a floor jack until it came together with barely a 1/4" gap left to close I heard a small bang, about like dropping a phone book on the floor from just a foot above the ground and voila! the motor and trans are together. Still I wonder if I simply forced them in a way that wasn’t supposed to be. In thinking about the length of the splines it would seem that when misaligned the motor and transmission would be held apart a full inch, or the length of the splines and even with the straps I used there is probably not enough pressure to force the shaft when misaligned. I guess there are two ways to find out.

I think stabbing an engine with the converter bolted onto the flexplate is a very difficult way of going about it.
Hopefully things fell together correctly. If not, you will know about it soon enough when the flexplate breaks; either immediately upon startup or 50 miles down the road.

I think I got off on the wrong track here. I’m doing this because the engine seized. Not sure why, but was told by two mechanics prior to the seize that the engine sounded like it had a broken wrist pin. Removing the bolts from the flexplate to the TC therefore was a little more difficult, not being able to turn the shaft. So in reversing my steps to reassemble I figured that the TC should be mounted to the engine first and then inserted in the trans. ok4450, indeed this is very difficult and now I’ve sufficient doubts to pull it apart and follow your suggestion. I know Tom & Ray would argue that in the interests of science (and defying laws of probability) I should probably try my way first. (Afterall it is almost all back together).

Just talked with my local auto parts guy, he says I probably ruptured a seal in the transmission and need to disassemble it. Not sure yet what this will cost to replace/repair so I’m keeping my fingers crossed or maybe they are just now stuck that way.

Four things have to happen to mate the Torque Converter to the transmission. First the nose of the TC has to enter the front seal of the transmission. Second the input shaft splines have to engage the hub of the turbine element. Third the stator support splines have to engage the hub of the stator one way clutch. Finally, the tangs on the TC nose have to engage the oil pump ears.

It is possible to pull the TC nose ontop of the pump ears. If you start the engine in this condition the driven element of the pump will grind into the rear of the pump housing effectively destroying the front pump. If you get a “no drive” condition after startup, suspect that this has happened. The bang you heard may have been an ear or both snapping off the driven element of the pump. In both cases the front pump will have to come off and be repaired to replaced.

I have never attempted to install an engine without the TC fully engaged in the transmission. In fact, a lot of service manuals will give you a recess measurement to determine if the TC is completely engaged.

What I would have done in your case is jump into the engine bay with the TC; quide it onto the front of the transmission; and used the offset of the flex plate from the back of the engine block as the minimum recess offset from the bell housing to a TC drive lug.

Hope you haven’t done major damage.

Jimbo, you will destroy that pump putting it together the way you did. Not only are you making this more difficult than it needs to be, you are going to end up tearing it down again and spending some $$ replacing the pump and converter. I you havent managed to get the trans back on yet stop what you are doing and remove the converter and inspect it real good. Also, look inside the pump and see if the drive tabs are still intact.


I have a very strong suspicion that the little bang you heard was the pump in the transmission breaking.

OK, thanks everyone. I will disassemble tomorrow and reassess. Maybe get some photos to post. Night!