Hi everyone!
Got a werid issue. So i recently reinstalled my Slim Jim transmission back onto my 64 394 engine. Remeber these have internal torque conveters, with that being said for some reason i caint spin the motor over with the trans flush to the engine. With a very small gap, i can put a bar on the crank and spin it over just fine. The transmission and engine are orginal. Please help!!

 

Your converter is not seated into the trans pump. You need to rotate the converter CCW &CW (not bolted to the engine)until the converter k-thunks into the trans(pump).
You may want to pull the pump and check for damage now while it's easy to get to.

 

It's a Slim Jim. Doesn't have a torque converter. Alex, do you have the damper plate (the disc with 6 springs) installed correctly?

 

Is there a procedure to installing the damper plate?

 

One of the FSM books covers the transmission. That book should have torque specs and the procedure for installing the dampener plate on the crankshaft. There isn't a trick to installing it, just make sure it splines correctly and is torqued to the proper spec.

 

I figured you would notice this thread Jesse, I remember your efforts with your old '64 98 in dealing with the Slim Jim in it.

 

Its very odd becuase the plate had been put in with the dowel pins properly aligned and i actually had the bolts slightly over torqued. I'm not sure what else it can be, maybe rust on the spines or dowel pins?

the questions is, what would make the engine get progressivly harder to turn as the trans gets closer and closer to the block?

 

With the engine removed from the transmission can you freely rotate the input shaft of the transmission?

 

Ooo I should try that, if the imput shaft doesn't rotate what does that mean?

 

Make sure the gear selector is in N or D when you try to turn the input shaft. You might have to disconnect the gear selector linkage if the transmission is already in the car.

If it doesn't rotate then there maybe some internal binding in the transmission.

 

Okay I'll have to give that a shot!

 

I havent taken the trans off quite yet due to the u bolts on the driveshaft, whitch are seized on. The one thing im positive on is the imput shaft is most likley hiting something or bottoming out. Im unsure how this is possible but i may have installed the damper wrong. How i tested that theory (Whitch this is NOT a good way to test it) is I put a floor jack on the tailshaft and gave the jack half a pump. The bottom bolts are in almost all the way. Every time the trans got closer to the block, it got tighter and tighter to turn the crank. Then i could no longer get it any closer using the weight of the engine & transmision. It had a 1 cm gap on the top of the bellhousing area.

 

I'm intrigued?
No torque converter...hmm!

So thinking down under ...here in Oz

Same same crankshaft and trans ?

Spigot bush maybe at the rear of the crank...won't take the input shaft?

And lose the u bolts at the diff and replace the rear uni, I reckon...been there too long. Just an idea.

Just more to the think about mate!

Cheers Paddy.

 

Was the transmission input shaft removed from the transmission? Will it go in backward with the ends of the shaft being different e.g. different depth splines? Can the flexplate be installed backward on these causing an offset in the wrong direction? I'm not an expert on the 394's just kicking around ideas.

Good luck!!!

 

The transmission needs to be disassembled to remove the input shaft. I suggest dropping the transmission completely and removing the driveshaft. I know this is a PITA, but that will let you determine if it's the engine or transmission that's binding.

If it turns out the transmission is binding you might be able to remove the pump from the front of the transmission and do a simple inspection. Be aware though that there are only a few shops in the nation with techs that can service a Slim Jim. If the transmission is toast you might consider a 455/TH 400 or LS swap.

Good luck!👍

 

Thank you all who responded! I am happy to say i figured it out! The damper plate was installed backward! Once it was reinstalled correctly, the engine turned like buter!

NOTE TO ALL FUTURE 394 REBUILDERS: the damper plate can be placed in backward. I was lucky to have a picture of the plate prior to me disasembling the enigine. MARK YOUR DAMPER WHEN REMOVING!!

 

As always, young'un- proud of you. Had a feeling you'd figure it out!😏

 

Glad you figured it out. It had been so long since I owned my 64 98 that I didn't remember that the dampener plate could be installed wrong.