Make a tool for efficiently removing the gearbox mainshaft bearings!
Turbo Mini Forums

Well - The bearings weren't coming out of my gearbox so easilly today; So - I made a tool to do the job. Last one I made disappeared and I've been talking about making another for a long time....

So - firstly - you need a tool like this from machine mart:


It's called a slide hammer. You can make one VERY easilly however - a piece of 2ft long 1/2"diameter bar with a cap / sleeve welded onto one end. You then need a suitable 'lump' of metal to act as a mass. Use your imagination / initiative - but it obviously needs to 'slide' along the bar and not past the cap/sleeve you've welded on there already!
On the other end of the bar, weld a M12 bolt - thread outwards of course. Congrats - your Very own slide hammer!

Now - this is the adaptor you need to make:



It's a 1st motion (bottom drop gear) nut welded to a 2" length of 1" diameter thin-wall tube. At the other end, weld in a M12 nut (will fall nicely inside the tube). All done!




To use:

Well - a picture paints a thousand words!



Screw the adaptor onto the 1st motion shaft. Screw the slide hammer into the adaptor.

Now - to use:



Hold the outer end of the slide hammer. Hold the 'sliding element' with your other hand, and slide it towards the transmission, then whack it backwards. Stand in amazement as the whole 1st motion bearing and shaft comes out with ease.
If it doesn't come out, then remove the slide hammer and hit yourself over the head with it before removing the circlip holding the bearing into the casing.



Now - the mainshaft dounble roller also benefits from this tool because the thread is the same in the 1st motion and mainshaft:



You need caution here though, as you can only draw the bearing out around 4/5mm before the 1st gear contacts the centre web - so don't use a lot of force...
What you can do though, is push the whole mainshaft assy back into the gearbox whilst putting a suitable wedge / spacer between the bearing circlip and web - hence preventing the bearing sliding back in.

Now you'll have a gap of around 10mm between lip on the end of the mainshaft and inner race of the bearing. Drop something in there like a small piece of aluminium to take up the clearance.

Now pull the mainshaft back and operate the hammer again.

By now you'll have enough of the mainshaft bearing ciclip exposed to get some pry bars (or screwdrivers for non-engineers) on to fully withdraw the bearing.

Jobs a goodun!

Edited by TurboDave16V on 24th Sep, 2009.

oh - DON'T hold the slide hammer in the area which is going to get impacted by the hammer. Firslty, the bones in your hand / fingers have a significantly lower impact strength than regular mild steel.
Furthermore, the cushioning effect of skin, flesh, and collapsing bones and cartlidge will reduce the effectivness of the 'impact' needed to withdraw the bearing.

Oh oh... Perfect for me, as I've jut made some tools myself :)
Let me get that camera out!

nice, and itll save you £70 or something

impressive, nice faq dave :cool:

I've seen the future and tbh its Pie

I don't know i f this tool is still available, but I bought it dirt cheap off Ebay:




Finally I had to make my own tool to remove the double roller bearing. This tool also was avaliable earlier. What you do is to knock the mainshaft towards the 1st motion shaft (after it has been removed with the other tool:) ) then fit this tool (when it's finished it'll ook like a C) between the double roller and 1st gear.
Thenjust knock the mainshaft towards the speedo housing side and hey presto... Finished :)

I might add. I also use the sliding hammer for removing idler bearings.

hhmm Veg, WE made that one tool not you

Looks like Vegard has been WRONG! again!

LOL!

Well, I was team leader. You were my slave. Of course I deserve all the credit!

hmm, I dont remember who it was that made that hole in the middle oval and ruining the drillbit? you worked on that lathe, not me:) I just watched you:)

Exactly, you did nothing! :)

I even broke something in the process!

this doesnt make sense Veg, first I where your slave, and then I didnt do anything? may I question your creditability?

Vegard has minimal credibility. There is nothing therefore to question. LOL

Hi,
Now steady on..... Refer the to the NO BITCHING post, please! Thank you!

LOL! I'd love to see you two in a workshop, must be a giggle! Can you post up a video?
Cheers,
Gavin :)

PS Nice slider hammer contraption Dave! (Note to self.....Must remember keep it On Topic )

Edited by Bat on 1st May, 2006.

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I just lost out on these on Ebay. Goody I (or Andrè, we haven't decided yet) mad my own :)

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...:MEDW:IT&ih=001

I have the 18G613 one which I would be happy loan out to TM members in a similar way to Dicanio's crank tap.

PM me and I will happily post the item out then return it with a cheque to cover my postage costs (agreed in advance).
I might ask new members to TM for a small deposit up front as these tools are difficult to come by now.

If of any use I also have:
18G572 Synchromesh Assembly Ring
18G617/2 which I think is the drift for replacing first motion shaft bearings in teh flywheel housing - unfortunately I don't have the other part of the tool for removing them!

Nice carpet Vegard!

On 5th Sep, 2011 Vegard said:
I stand corrected. You should know

ha ha! I guess you are not able to see it in the mirror yet though