ausmini
https://www.ausmini.com/forums/

Gearbox Build Trouble Out Put Shaft Bearing
https://www.ausmini.com/forums/viewtopic.php?f=2&t=46868		 Page 1 of 1
Author:  matt van'74 [ Tue Oct 21, 2008 8:21 pm ]
Post subject:  Gearbox Build Trouble Out Put Shaft Bearing
Hi Everyone,

I am having some trouble with my gearbox. Its a mk2 S box not that that is of any great importance.

I am in the middle of completely rebuilding my gearbox but am having trouble with the bearing retainer and the amount of load it applies to the output shaft bearing/double row bearing. When I have the bearing retainer finger tight the input gear and therefore everything else turns freely whether it is in neutral or engaged in gear.

However once I do up the four bearing retainer bolts it is much harder to rotate and if I select a gear it binds up. By this I mean I cant turn it by hand, I havent attempted to turn it by any other means.

I have assembled the bearing retainer free of shims to figer tight and measured the gap to be 0.010" between the retainer and the face which it bolts to. Just like explained in the Manual. I have exactly 0.010" of shims but still the problem persists.

Obviously the bearing retainer applies force to the outer race of the output shaft bearing to "retain" it in its position but obviously mine is loading it up. I have assembled a few now and have never had this problem.

Has anyone had a similar problem or know of where I might have gone wrong.

Thanks in advance,
Matt
Author:  justminis [ Tue Oct 21, 2008 8:39 pm ]
Post subject: 
Matt, have you got the pinion and 1st motion nuts torqued up? If not, try this, it may settle things where they are supposed to be.
Author:  TheMiniMan [ Tue Oct 21, 2008 8:43 pm ]
Post subject: 
Im thinking you may have a "grabby" syncro ring somewhere???

No crack in the centre case web???

Have you fitted the circlip onto the double row bearing??? (That should actually show up easy tho because you wouldn`t have been able to shim the bearing retainer up properly,,, but still it`s just a thought) I know someone who forgot that circlip once :-) Just once tho :-)

Not fitted the inner selector hubs around the wrong way???

ar,,, er,,, um,,, i`ll keep thinking for you, but if it were me then i`d rip it all apart & have a dam good look at everything before putting it all back in again

i`ll keep thinking for you tho
Author:  matt van'74 [ Tue Oct 21, 2008 8:56 pm ]
Post subject: 
justminis wrote:
Matt, have you got the pinion and 1st motion nuts torqued up? If not, try this, it may settle things where they are supposed to be.


They are not at 150 ftlb but are firm. I thought about this too and will try to torquing them up tomorrow and see if it works. Thanks for your help.

TheMiniMan wrote:
Im thinking you may have a "grabby" syncro ring somewhere???

No crack in the centre case web??? No it all looks okay

Have you fitted the circlip onto the double row bearing??? (That should actually show up easy tho because you wouldn`t have been able to shim the bearing retainer up properly,,, but still it`s just a thought) I know someone who forgot that circlip once :-) Just once tho :-) Yes I have fitted the circlip and it is all the way home against the centre web.

Not fitted the inner selector hubs around the wrong way??? No I was pretty precise about this as I had heard that they could go on wrong and cause big dramas.

ar,,, er,,, um,,, i`ll keep thinking for you, but if it were me then i`d rip it all apart & have a dam good look at everything before putting it all back in again

i`ll keep thinking for you tho Thanks


Thanks for your input Matt. Like you said I think I will ultimately be pulling it apart again tomorrow.
Author:  BALLISTIC [ Tue Oct 21, 2008 10:54 pm ]
Post subject: 
Is it possible that the bearing is on a slight angle and when its sitting on the selector forks its causing a load as they are straightening the inner bearing race straight.
I have a feeling that the double row bearing is not all the way home as i cant think of anything that would cause the bearing its self to load up when you only tighten up the retainer but i could be mistaken/corrected.
Unless one of the selector forks is bent slightly or not fitted 100% in the correct position.

:oops: The only time i had the third motion shaft tighten/load up on me when i fitted one of the selector hubs around the wrong way.......and it to was in a remote change g/box..........as Matt says......it only happens once!! Its a pain in the ar$e as you have to pull it all apart again without damaging the bearings :oops:
Author:  TheMiniMan [ Tue Oct 21, 2008 11:28 pm ]
Post subject: 
ha ha ballistic i had to copy & paste your "Fine print" & shove it into "word" program & enlarge it to be able to read it

:-)

I`ve never actually done that one myself,,, but i`ve seen heaps of people do it :-),,, but i have left out the circlip on the double row bearing once... but i blame my dad as he was rushing me & all upset at the time so i was distracted,,, & yeah you usually only stuff these things up once & learn from them :-)

I have seen a cracked bearing outer race tho,,, it doesn`t often show up when just sitting there on the bench tho,,, but once you apply some load the dam thing opens up like the grand canyon,,, only problem is that it`s really hard to see in there with the retainer in the way,,, i doubt this is the case here tho as i suspect he`s used brand new bearings yeah?

anyways,,, i`m sitting here typing more on my twinky build guide but all the time thinking of more possibilties for this problem :-)

I`ll try to get to bed in an hour or so :-(
Author:  BALLISTIC [ Tue Oct 21, 2008 11:44 pm ]
Post subject: 
:shock: I'm sure you laughed at that Matt!! :wink:
I did that at the end of a very long day in the workshop and when i realised what i'd done i got the $h1ts and went to bed.....(it was 3am and id been going since 6am the day before, funny i really havn't worked those hours since) anyways it was quickly fixed after some sleep and with a clear mind.

Anyways good luck with the twinky build guide....the fun part .....Not!! :lol:

ive been trying to think of what else but come up with nothing really other than the 1st motion shaft and single row bearing are not lined up properly and causing it to load up once pressure is applied at the other end.
Author:  TheMiniMan [ Tue Oct 21, 2008 11:51 pm ]
Post subject: 
yeah i`m with ya mate,,, i used to do all nighters because it got to the stage where time just dissappeared & suddenly i realise that it`s 330 or 4 in the morning & figured why bother going to bed cause i`m only going to wake up all grumpy & horrible with only a couple of hours sleep so i kept working right through,,, did that heaps of times until i ended up in hospital, but that`s another story :-)

People can put the first gear roller spacer around the wrong way too,,, seen that heaps of times but i`m just trying to remember what actually happens when that`s done,,, ??? I`m sure it binds things up too but think it`s only when the pinion nut it tightened.... ah,,, there`s so many possibilites & it`s so hard without the box infront of me & it`s too late,,, i`m going to bed,,, :-)
Author:  aaron [ Wed Oct 22, 2008 1:29 am ]
Post subject: 
Matt you are correct the spacer will cause it to bind. The problem lies in the fact that there is a manual(not sure which one now) that has an exploded view with this spacer back to front....... Thats why i have at least 5 different publications.... out of all them, you can "Almost" put a mini back together properly :lol:
Author:  matt van'74 [ Wed Oct 22, 2008 6:33 am ]
Post subject: 
Thanks for all your help,

Matt, I have used all new bearings, a new lay gear and shaft, a good SH mainshaft. And a good SH gear set.

Scott, your theory makes sense and I will check how flat the bearing is sitting. And that it is all the way home.

I will double check that I have fitted the first and second synchro hub around the right way.

I will double check everything when I pull it apart tonight.

Thanks
Matt
Author:  peterw [ Wed Oct 22, 2008 9:31 am ]
Post subject: 
The C shaped cast iron frame that holds that double row bearing in place is normally shimmed. If you don't have the shims in it could tighten up.

Pete
Author:  matt van'74 [ Wed Oct 22, 2008 6:29 pm ]
Post subject: 
peterw wrote:
The C shaped cast iron frame that holds that double row bearing in place is normally shimmed. If you don't have the shims in it could tighten up.

Pete


Thanks Pete, I had 10thou worth of shims in there but for some reason I measured it wrong. It was actually a 17 thou gap so I have 16 thou worth of shims in there now to give 1 thou crush.

I suppose I should use the old saying " measure twice cut once." I am not sure how I managed to get 10 thou as it is a fair way away from 17 thou but I did have the outputshaft nut loose when I measure it the first time.

So in the end this was all it was, me measuring it wrong.

It all turns freely and works as it should. Thanks for all the input.

Matt
Author:  BALLISTIC [ Wed Oct 22, 2008 7:52 pm ]
Post subject: 
:D Very glad you didnt have to pull it apart again and it was so simple :!: Like Matt said ....its hard to diag without it in front of you as there are many possibilities. Hope it goes smoothly from here :D
Author:  matt van'74 [ Wed Oct 22, 2008 9:42 pm ]
Post subject: 
BALLISTIC wrote:
:D Very glad you didnt have to pull it apart again and it was so simple :!: Like Matt said ....its hard to diag without it in front of you as there are many possibilities. Hope it goes smoothly from here :D


Thanks Scott, I am glad too. I have got it all pretty much back together now and it selects all gears using the gear lever on the bench. An hours more work I think and it will be done.

It has all gone really well minus me being an idiot causing the one hiccup.

Matt
Author:  BALLISTIC [ Wed Oct 22, 2008 10:55 pm ]
Post subject: 
matt van'74 wrote:
BALLISTIC wrote:
:D Very glad you didnt have to pull it apart again and it was so simple :!: Like Matt said ....its hard to diag without it in front of you as there are many possibilities. Hope it goes smoothly from here :D


Thanks Scott, I am glad too. I have got it all pretty much back together now and it selects all gears using the gear lever on the bench. An hours more work I think and it will be done.

It has all gone really well minus me being an idiot causing the one hiccup.
Matt


Not an idiot ........just missed 1 minor detail which was 7 thou of shims, couldv'e been worse, you couldv'e put it all together with the "she'll be right theory" and it wouldv'e ended in tears :!:

catch ya later
Page 1 of 1 All times are UTC + 10 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/