Separating front half of transmission case from adapter plate

[SoCalJim]

I’m a bit stumped on how to separate the front case from the adapter plate on the 5-speed I’m eventually going to put into my 280Z.  I’ve removed the front cover, washer, and snap ring for the main shaft, and I’ve removed the large snap ring for the main shaft bearing.  The FSM says to tap the case off the adapter plate with a soft hammer; however, I can’t seem to get them to separate.  Is something that’ll require really wailing on?  I’m really reluctant to go all primeval on it for fear of damaging something.  Any advice or pointing out my stupidity would be greatly appreciated!  Thanks!

[Zed Head]

Can't remember for sure but I think that I found an edge on the adapter plate and used an aluminum rod to break it free from the front case.  As you're finding there's not much to bang on otherwise.  Somebody might have used a strong sealant on yours.

[cgsheen1]

Looks like they did on the rear cover. Can you get anything between the cover and the plate to cut the seal (slim putty knife)? Have you tried standing it up with the input shaft on a board (tail straight up) and tapping the front cover downward.

[SoCalJim]

The rear cover came off with very little difficulty.  I tried standing the tranny on the main shaft to tap the front cover downward, without success.  I didn’t want to get on it too vigorously, as I was concerned that I could tweak the shaft,

[Zed Head]

2 hours ago, SoCalJim said:

tap

Swap tap for pound...

[Dave WM]

4 hours ago, SoCalJim said:

The rear cover came off with very little difficulty.  I tried standing the tranny on the main shaft to tap the front cover downward, without success.  I didn’t want to get on it too vigorously, as I was concerned that I could tweak the shaft,

sorry did not see the pic, do what ZH said pound on it right at the junction of the adapter plate to front case. Use a hard plastic hammer and wail on it. get ready for it to suddenly separate, and break the oil trough.

IIRC I set mine on some 2x4 to keep the input shaft clear and it standing upright, then hold on to the output shaft, bang up on the adapter plate, just catching the edge.

Edited November 21, 2019 by Dave WM

[SoCalJim]

Great!  I’ll give that a try.  I’ll swap out my rubber mallet for my plastic hammer, and  I’ll also switch to pounding.  Thanks guys!

Edited November 21, 2019 by SoCalJim

[Dave WM]

if you watch the guy "villageland" on YT, he shows how he does it. Really wails on it with a small sledge, kinda scary to watch without sound. I cant recall how hard it was to remove mine, but I do recall finding that darn oil trough, I keep going back to it since it was so easy to break if you don't lift the adapter plate off straight up. You can buy replacements but they seem softer and maybe weaker that the orig. You don't want to lose oil supply back to the tail shaft bushing.

[SoCalJim]

Thanks Dave!

[SoCalJim]

I stood the transmission on my moving cart to keep the input shaft from hitting into the floor, etc.  After also spraying the bolt holes and the edge of the front cover-to-adapter plate mating surface with CRC Gasket Remover and PB Blaster, and letting them soak for a while, I started hammering upwards on the protruding edges of the adapter plate.  Eventually, it gave in and the cover and adapter plate were separated.  I only hammered my hand once and yeah, it’s black & blue.  Thanks for all the advice on getting them apart.

I looked at the oil gutter and is the orientation correct?

The counter shaft front bearing (ref. parts figure, circled in red) didn’t have a shim in front of it.  I hope these are still available.  The bearing also feels like it has a lot of play in it, so, I’m going to replace it.  The main drive gear front bearing (circled in blue) doesn’t feel as smooth as I’d expect, but it feels a lot better than the counter front bearing.  I’m thinking about replacing it, too.  The gears look like they’re in good shape, although there’s some errant sealer here and there on some of the teeth.  Obviously, someone was in this tranny before and was sloppy.  In addition, the rear case was cracked in a couple of places and was RTV’ed on the inside and painted over on the outside.  So, I got to spend a little more money getting that case welded up.  Oh well, eventually I’ll have a 5-speed!

[Dave WM]

its looks fine, just has to catch oil sling and send it on down the line.

later transmissions increase the size of that counter bearing, so I presume it was deemed too small.

The shim was not stuck up in the front plate was it?

[SoCalJim]

No, unfortunately it wasn’t there.  I’m looking online for them but so far, no luck.

and thanks regarding the oil gutter, Dave!