Hello! I have a bit of a... Stupid question, though I'm a little stuck with my project car and could use a little help. Bear with me here, I've never pulled an engine before. Long story short, I picked up my first car, a 1964 Grand Prix, a couple years ago. Has the 389 with the Carter 4-barrel paired with the dreaded "Slim Jim" 3-speed. Got it all sorted out over that fall/winter and started using it as an (almost) all season driver/cruiser, that was up until recently. The motor is original to the car and had about 75,000 miles on it last time I checked and started to show signs of needing a rebuild. I've never rebuilt an engine before, though I figured you gotta learn one way or another. The plan was to pull the engine without yanking the transmission, mostly due to a lack of space at the moment. When I went to pull the 389 the other day, the Roto wouldn't budge from the back of the motor. I looked over my service manual and all I could all over the internet and I'm fairly certain removed all the necessary bolts and pieces holding the trans to the motor including: Six bellhousing bolts Six bolts connecting the damper plate to the flywheel Both flywheel cover/service plates Starter TV Rod linkage/any other linkages I've tried separating the two using a prybar, rocking the engine, etc., and nothing has worked so far. The only thing that I could think is that I'm working on a slight downward slope and maybe I need an engine leveler? Maybe the cold isn't helping? If anyone's familiar with this trans, I'd greatly appreciate any advice, thanks!
Six bolts..That's it. Dampener is a slip fit..At least when new. Apparently yours has seen better days. Keep doing the Watusi , holding on to one or the other.
That should come right out.. I have to think about this one.. Are you keeping the slim jim. There not as bad as everybody makes them out to be..They have a real cool veritable first gear that the vanes in the torque converter change as rpm goes up. Then they shift into second which is grounded and it feels like the stick car.. I had one behind a 421 in a 64 GP that ran its ass off, I mean the car was real fast..
Chances are the alignment dowels are stuck tight, as they are usually a pretty tight fit. A little rust and corrosion don't help, plus any angle you're pulling at isn't going to make it any easier. Some penetrating juice, and a little heat where the alignment dowels are might help. Here's a photo of what I believe to be a Pontiac version of the Slim Jim trans, and where those two dowels are. When you say the cold may not be helping, I sure as hell hope you're not trying this outside in the Michigan winter. If you are, dammit you're one hell of a lot tougher than I am.
Just re-read this.. With the engine /trans still in the car, you can use the engine weight to help you . Jack both up together, then block the trans to the floor. Take a little weight off the engine.See if it starts to separate at the bell housing. If it does, then it's probably not the dowels, although shooting some WD on them won't hurt. Keep moving the engine up and down a little while pulling on it. The damper plate is a dry spline, and they started to rust when only a few years old. Even spraying some soapy water up in there, behind the flywheel might help.
Ahh, the alignment dowels. I completely forgot about those, I'll have to get in there and spray some fluid and break out the torch, I'm sure that'll help a bunch. Thanks! And speaking of cold, haha, yeah working half in the garage in 25 degree weather. Sure wish I got everything out sooner, working in this weather is a pain sometimes. Maybe it's time to move South.
I will also make sure to give this a shot, I appreciate the advice. Sounds like it could be a combination of things; I had the engine out briefly at a close friend's shop back in late 2016 (granted I unfortunately wasn't around for the most of the process) so I'm not surprised if I have a little corrosion up there.
I really wanna keep the slim jim, at least until it goes. Like the motor, it's original to the car and I'm honestly surprised at how well it still works, considering the age and the fact the car sat for 10-12 years in a barn. The only issues I'm having is a very late downshift problem, which either goes back to the TV rod or maybe the fact that the engine was definitely down on power, and a leak at the front seal, which I could probably replace with the motor out(?). It also likes to vent tranny fluid when it gets warm, whether it's undefilled or overfilled. Other than that, I love it.
You'll get it. Especially if it has been out before. I should have mentioned earlier. Block the trans up and leave your two top bolts in but about a quarter inch loose.Then lower your hoist and see if the block pulls away on top. If it does, pick it back up a tad, remove the bolts ,and wiggle the hell out of it, up and down at the water pump..It'll come out then.
''There not as bad as everybody makes them out to be..'' Ha Ha Ha Ha Ha …. I fondly reminisce about the '64 Catalina we got in the shop in 1969 … the Roto had burnt itself down & left a traveler stuck here in town. We hurried to help him out - called dealer & bought a new-in-the-crate trans. Stuffed it in & took off to road test … it shifted into high going over the Pancheri overpass & never came back out. Did all the troubleshooting steps, re-adjusted everything, no fixee. Jerked it back out & returned it to it's crate & the dealer. They didn't have another one, so the car ended up at a local trans shop where they repaired another used unit to get him going.
Once you read up on them and understand how they work you might come to enjoy them. I had to change driving habits when I had that GP. I remember always manually shifting that car, holding it in L or S.. If you are racing it you just leave it in L and let the governor do the shifting.. Back in the 60s, B&M put out a performance upgrade for the Roto. I always wanted to try it.. Back in the early sixties my neighbor had a real nice 63 Catalina two door hardtop, dark red with black interior. ET mags in the front and black painted stock steel wheels in the back with chrome lugs. It had a 421 with dual four barrels and a Roto Hydro. I remember one day he was installing a B&M shift kit out in the alley. After he was done tsting and adjusting everything he took me for a ride. Wow did that car scream across the 40th street bridge.. I remember holding on to the dash bar.. He was laughing as he was cranking it up saying wow what a difference! That Pontiac used to be one of the fastest cars in the neighborhood and there was a lot of fast cars then.
I mus have had a dozen of them. Even tried racing one in a 63 GP, 389, Tri Power. Gave up and put a 4 speed in it. A friend, who had a garage and a wrecker, used to say, they'll leave you at a stoplight. He'd go out and hook 'em up, right there. I had a 64 Cat wagon and I goosed in low on a highway ramp, one time ..The minute it tried to shift 2nd, I had a box of neutrals, right then and there. Amazing that they were only one year away from a 400 turbo.
I had a couple of them behind a 394 Olds, one was a serial leaker, once I pulled it and sealed it, it was fine. That '64 88 went like a scalded dog.
I had a 61 Pontiac Bonneville that I believe had a slim Jim transmission behind the 389 tri power engine. The transmission worked fine with the vacuum operated end carbs, but didn’t hold up well when I put on progressive linkage on the tri power. I replaced it with a 3 speed and all was well again
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