Getrag 245 Bolts and Whatnot Identification

[MattL]

Can anyone tell me what the labeled bolts/plugs are in the photo below? Couldn't figure it out from Realoem.com. 

 

 

[TobyB]

Well, I'll let others give you a hard time about B.  

But if you're using this transmission, replace it with the B from your 4- speed.

 

A looks like the plug over the primary selector rail detent plunger 23317545771

 

and I can't find C, either.

 

Neither A nor C are usually disturbed unless you're taking the transmission apart.

 

The big cap behind A is the 5th- reverse detent spring, and if the transmission ever

refuses to go into the 5th- reverse gate, removing this cap (and catching the spring with your teeth)

takes pressure off that detent.  The detent itself has been known to rotate and jam...

 

t

 

[MattL]

14 minutes ago, TobyB said:

Well, I'll let others give you a hard time about B.  

But if you're using this transmission, replace it with the B from your 4- speed.

 

A looks like the plug over the primary selector rail detent plunger 23317545771

 

and I can't find C, either.

 

Neither A nor C are usually disturbed unless you're taking the transmission apart.

 

The big cap behind A is the 5th- reverse detent spring, and if the transmission ever

refuses to go into the 5th- reverse gate, removing this cap (and catching the spring with your teeth)

takes pressure off that detent.  The detent itself has been known to rotate and jam...

 

t

 

Thank you, Toby. To clarify: that fluid all over “B” is penetrating fluid, not tranny oil. It’s not leaking. (In case that’s the reason for the suggested replacement and hard time I’m in for.) ?

 

I was HOPING “A” might be detent-related, since I in fact am having that precise problem! Unable to access either reverse or fifth. I’ve got the transmission on the bench in the hopes I can poke and tickle it sufficiently to fix it before taking it apart. Do you know I would go about getting that blind cap off? Or is that foolish? I’ve already removed and reinstalled and adjusted the angled detent plug, spring, etc. without more than a temporary success in accessing fifth. 
 

Thanks again!

[2002]

Item "C" in your picture is called a blind plug and can be seen as item 15 in:

 

https://www.realoem.com/bmw/enUS/showparts?id=1733-USA-06-1981-E21-BMW-320i&diagId=23_0707

[MattL]

Right you are, Steve. Thank you. Looks like it holds another detent plunger and spring. Any idea how to get it off? Or are blind plugs no-touchey? 

 

(The reason I'm fiddling with all this stuff is that my transmission (not installed) will not shift into 5th or reverse. The 5th gate is accessible, but the selector rod won't then pull back into gear. On the reverse side, the gate is there, but not accessible. As I rotate the rod towards the gate, there's a grinding but it doesn't go in.)

[2002]

When we rebuilt my 5 speed it was taken completely apart.  We used a small chisel to remove the plug, and then used some thread sealant (see link below) on it to hold it in before applying a small hammer to it!

 

https://smile.amazon.com/gp/product/B0002UEOP0

[TobyB]

If you're not selecting 5th or reverse, take the big cap off behind A.  It will try to launch,

so be careful.

 

Pull the outer plunger, and see if it now freely selects 5th and reverse.

 

If it does, replace the plunger, paying close attention to the orientation of the flat on the plunger- it should be

turned so that the tapered side resists 5th, the less- tapered side resists reverse harder.  If you get it wrong, you'll know!

 

https://www.realoem.com/bmw/enUS/showparts?id=1733-USA-06-1981-E21-BMW-320i&diagId=23_0709

 

And you're right, Steve, C's the main detent plunger cover.  I forget that the selector on a Getrag's way far forward.

 

B's the fill plug, btw...

 

I guess A would be another rail detent plug, but...

 

t

 

[MattL]

11 hours ago, TobyB said:

B's the fill plug, btw...

 

Aw, jeez... Of course. My doofus game is strong. 

 

I actually have completely removed the big cap, spring, and inner and outer plungers. It didn't really try to launch; just a little compression present. In any case, no change: 5th and reverse still not accessible. And I've reinstalled them, careful to ensure they're oriented per the diagram, which seems to match your description:

 

 

Looking at that main selector detent on Realoem's diagram, I don't think anything there would explain the issue. The selector rod definitely hits -- and then travels through -- those up-and-back detents across neutral. The grinding I encounter when trying to push into the reverse gate doesn't "feel" like it's at the shaft itself, but rather at the end of the "shift" (as Realoem calls the v-shaped part at the end of the selector shaft). And although there's no grinding when I go for 5th, it is a solid, unyielding wall. (My "temporary success" must have been 4th, rather than 5th, in retrospect.) 

 

I think the reverse/5th shifting rod and/or fork must be stuck. So, the decision I have to make is whether to continue to disassemble or take it to a pro. My big hesitation about disassembling it myself is the possibility of damaging some NLA part. All I've really exposed so far is the input shaft bearing, but that was enough to give me sweats. 

Edited June 29, 2020 by MattL

[TobyB]

Ah, the usual problem is that you can't get the selector to move to the 5th or reverse gate.

 

If it moves into the gate, but then can't engage the gear (push up, in shifting perspective)

something else is wrong.  In that case, it's very odd that both 5th and reverse are balky.

 

I have taken apart one 5- speed, and never reassembled one- and I've repaired a half- dozen

transmissions over the years.  So if the input bearing cover gives you agita, look for a pro.

They're not common, but I think there's someone in Philly...  

 

t

[2002]

Lever encircled in red is the one that controls the selection of reverse or 5th gear.  The bolt extends through the to of the case.  When my 5 speed was disassemble we found this piece in the bottom of the trans.  Perhaps it is what makes the other gear grind.  Looks like you'll have the take the whole thing apart to make sure.  As you can see there is no part number listed for this on on:

 

https://www.realoem.com/bmw/enUS/showparts?id=1733-USA-06-1981-E21-BMW-320i&diagId=23_0707

 

Good luck!

[MattL]

That sounds like a likely candidate, Steve, thank you! 

[2002]

After removing the rear cover, this pic shows where the lever goes:

 

Edited June 30, 2020 by 2002

[MattL]

Thanks for the continued help, Steve. I checked last night, and that bolt is definitely not attached to the lever. After unscrewing it carefully, I looked into the hole and could see the lever down there, but no hole for the bolt. Not surprising. I was able to fit a thin pick tool down there at an angle, hook onto the hole hidden from view, and drag it carefully to directly under the case hole. I don't imagine I'll be able to get the bolt threaded in without taking the case apart, but I'll give it a shot. 

 

Is it okay to just remove the rear cover? Or is it necessary to follow the order of operations in the manual, i.e. front cover, then rear cover? Either way, I'm very encouraged to have a likely culprit that is something other than a munched gear or something! Extremely grateful for the ideas and assistance!

[2002]

Matt,

 

You'll probably need to remove the front cover first, but it might be worth trying the rear cover first.  Anyway you'll probably need a puller to get the rear cover off.  Pay attention the locations of the 6mm bolts in the output flange.  The shorter on goes in the 1 o'clock position.

[MattL]

@2002 

 

Hey Steve: you are a life-saver! It was definitely the operating lever, and after some trial and error and thinking it through, I got it sorted without taking the box apart any further. I posted an update here: