Successful gearbox removal

[Hairy Bobis]

I am feeling well happy after successfully removing the gearbox from my 1.0l '95 Micra.

After much researching on this amazing forum and studying the book of Haynes, I was able to extract my gearbox.

I did have some problems of stubborn bolts on the bottom of the bellhousing. When I thought I had removed all the bolts, the box would not budge until I realised I had missed a bolt attaching the rear engine mount. I did not appreciate this attached to the gearbox and had to be removed.

However I note from the manual of Haynes it makes reference of disconnecting the exhaust, I found this was not necessary.

Overall it was easier than expected. Finding a replacement is proving harder though.

I might be brave and open the box up to see what has caused the failure!

Here are some piccies.

 

[r-reg-sr]

That's a nice box that is iznit

 

[SuperUno]

With the red sealant marks that box has been apart before..... also fit a new clutch whilst it is apart yours looks well worn.....

 

[pollyp]

as a reference, this is what a 1.3 gearbox looks like inside

http://micra.org.uk/threads/pollymobiles-rebuild.35251/page-11#post-419711

 

[Skinner_87]

Good job

It must be gearbox night ive got mine in 2 as well!

 

[Hairy Bobis]

Yes, the gearbox has been apart before. When we bought the car from Curries Motors in '99 the gearbox got a little noisy and we had it rebuilt under warranty.
I did request for the clutch to be replaced as well, however how can you prove this?

SuperUno, I was not considering in changing the clutch but it seems daft not to while the 'box is out of the car. How can you tell the clutch is worn without removing the cover?

I hope to get my 12mm hex socket on Friday, I have a stubborn bolt on the gearbox, all the others loosened ok apart from one. Then I will be able to open the box up and see what bits I have floating around.
Cheers.

 

[pollyp]

just like checking the brake pads, you could peak through the side opening of the pressure plate to see the clutch plate (thin metal disc with friction material on both sides) being clamped between the flywheel and the pressure plate. quick visual inspection is if it's been replaced, then there should be a thick amount of meat left on the clutch plate plus would be able to see the 1mm groove slots on the contact end of the clutch material.

if it's worn and/or abused then it'll appear very thin with no visible groove edge.

but tbh for more accurate diagnostic you should just remove the clutch and check it's actual thickness with some calipers. think they're 7.5mm new?

if the clutch was very used and kept being reused to the point where it badly scores the flywheel/pressure plate and/or makes a bad metal/metal grinding noise then it's game over n the flywheel either requires resurfacing or replacing. that's why it's always advisable to replace the cheap clutch assembly if it's been fairly used, whenever the gearbox is out.

 

[Agent_Sm1th]

Perfect opportunity to lighten that flywheel as well eh.

 

[SuperUno]

The fingers where the release bearing sits look worn to me in your pic, and whilst you have it apart you may as well change it anyway.

 

[Hairy Bobis]

Looks like I will be finally using my clutch alignment tool I bought many years ago!

Hopefully I will have the 'box open this weekend.

Thanks for the support.

 

[frank]

good luck HB, i,ve stripped 2 of our type 41 g/boxes, and thought !! i wont be re-assembling this they come apart differently to the later type 30 ones btw (there is a full rebuild chapter in the k10 haynes manual)

 

[truck+micra matt]

Where ya based I've got one in my garage from my conversion to a 1.3 engines naff but box is still good

 

[solarice]

there is a full rebuild chapter in the k10 haynes manual

Always amazed me the mentality of the haynes manuals between k10 and k11 version on gearboxes. K10 yeah this is how it goes with a massive exploded diagram. K11 version eek its full of witches and snakes keep away.

 

[Hairy Bobis]

Frank,
I am surprised there is a full rebuild in the K10 Haynes manual, not so in the Haynes K11 manual I have. I will have a look out for this. I understand the early K11 'boxes are an adaptation of the K10 'box.


Truck & Micra Matt,

Many thanks for your kind offer, I am situated very near to J13 of the M25. Am I close?

 

[r-reg-sr]

my part of town ,,,,,,,,,, finders keepwers

 

[truck+micra matt]

I work in Braintree and live near Clacton so Essex based you sound like your south m25 ?

 

[truck+micra matt]

Oh is 60 a fair price?

 

[Hairy Bobis]

Truck & Micra Matt,

You are most kind, I would like to take you up on your offer.

Before I make the journey, are you 110% sure your 'box is a preface lift '93 to '97 1.0l 'box?

Thanks

 

[truck+micra matt]

It's out of a micra reg L415ULW it's the 93 model 3 door

 

[truck+micra matt]

Can't turn the pic but

 

[truck+micra matt]

Oh my smart phones just dumb lol

 

[Hairy Bobis]

Well, this afternoon I started my investigation.

I took the cover off and could not see much wrong. Slowly, with my magnetic wand, I started to extract small bits of metal. But I still could not see much wrong with the gears.

I delved deeper and, well, I will let the pictures do the talking!

The word 'fubar' springs to mind!

 

[SuperUno]

Wow that is knackered! What caused that to happen? Diff bearing failure?

 

[frank]

driven shaft/output shaft bearing eh, just milage i guess

 

[Hairy Bobis]

I believe it was the main shaft bearing. The part that joins the casing. The shattered bearing then chewed some teeth and mullered the casing.

Apologies if I have named the wrong part.

 

[Hairy Bobis]

Frank, not really, the car has only done 55k. I am baffled.

 

[joakwin]

That's the same bearing that went out on mine as well, the bearing and plastic thingy was like 18quid, it was a smaller bearing as well, the face lift box uses a bearing that is a hair bigger

I have all the parts beside one shift fork to rebuild a early box,
You can have them, but the only problem is that I'm in Germany till the end of oct

I'm moving in dec so if I can't give the parts away they will end up in the recycle center or the bin

 

[truck+micra matt]

What happened in the end is it alive?

 

[Hairy Bobis]

Matt,

I was good meeting you last weekend.

Not yet, been too busy.

I did start cleaning the outside of the box. I hope to get it on before the end of the month, if it stays dry outside.

Just need to get some differential oil seals and some GL4 oil before it goes in.

I plan to do an update on here and hopefully get her MOT'd.

 

[Hairy Bobis]

In the latest saga I have now removed the clutch. I would be grateful if those with the knowledge can advise if it can be reused.

The car has done 55k and the 'box was rebuilt by Nissan under warranty at 22k in 2000. They said they replaced the clutch.

The clutch plate thickness is 7mm, within the 6.7 to 7.3mm range per Nissan. The depth of the rivets are 1.25mm on the flywheel side and 0.90mm on the clutch cover side. Easily within the 0.3mm wear limit per Nissan.

However do these pictures tell another story? Guidance will be much appreciated.

 

[frank]

looks 2 x healthier than mine, and i refitted mine

 

[pollyp]

looks to have plenty of meat left on that and no heat stress. check the clutch plate springs ain't loose

 

[SuperUno]

Pics of the clutch finger springs?

 

[Hairy Bobis]

Thanks Pollyp, I will have a look this evening at the x4 springs.

SuperUno, there is a picture in an earlier post of the finger springs while the clutch was still attached to the flywheel. It show a 'clean' ring where I think the clutch release bearing makes contact. I do not think there was a ridge along this ring but I will check this evening and take another picture.

Thanks for you replies.

 

[SuperUno]

If there is a ridge then I would fit a new clutch, for the sake of about £50 do you want to go through the same effort if the clutch lets goes due to it being worn?

 

[Hairy Bobis]

The next episode.

I managed to get the relevant parts together for the next episode. These being a new LUK clutch kit, x2 diff seal, and 5l of GL4 slippery juice.

First job was to replace the diff seals.

Then I spent some time making sure where all the bolts and brackets went.

After it was time to insall the new clutch, clean the mating surfaces on the flywheel and the clutch plate.

Now everything was going smoothly, too smoothly. I tried to fit the gearbox and the bu@@er would not go in. After 10 minutes of trying I sussed out why.

Can you see why?

I have got 3 dowels!!

Can anyone suggest how I get the duplicated dowel out of my replacement gearbox?

Many thanks.

 

[frank]

the dowels just pull or drift out HB

 

[truck+micra matt]

Had that issue before we hammer an blowtorch but that was on a pug but those from memory you can use a nail punch on the back and pop them out?

 

[pollyp]

I used mole grips

 

[Hairy Bobis]

Thanks for the replies.

I think I will try and remove the dowel from the gearbox, this being easier to access than the recess of the engine bay beneath the inlet manifold.
I am worried about cracking the gearbox bellhousing casing around the dowel.
Now where did I put my mole grips!

 

[pollyp]

after removing the dowels, wirebrush em clean from rust, file / grind down any raised metal markings from the mole grips so it won't jam in the hole and smear bit of copper grease.

 

[joakwin]

How was the adjustment of the clutch before the bearing went out? On my gearbox, that main shaft bearing went because the clutch was adjusted so lose that when the pedal was pushed, the clutch wasn't moving, so every gear change was like power shifting

I got the car with the box making a sound and a week later the bearing went

 

[Hairy Bobis]

Joakwin,

The clutch was working fine before the failure, so I am hoping all will go ok this weekend (weather permitting) when the 'box will be back in.

Famous last words (he touches wood).

 

[Hairy Bobis]

More progess has been made last weekend, we have finally made contact!
That being engine to gearbox contact.

After spending an hour or so I managed to line everything up and mate the gearbox to the engine. It was a struggle to line it all up but eventually it fitted.

Then I carefully made sure that all the bolts were reattached , including the rear engine bracket. The driveshafts clicked in smoothly and the starter went in without a hitch. The gear linkage to the gearbox was a fiddle but it went in eventually.

The next test was filling up with 3 litres of slippery juice of GL4 vintage. Success acheived as there were no leaks.

Next to connect was the speedo drive, reversing switch cable and the clutch cable, fairly straight forward then I got stuck!

It amazes me how you make every effort to remember where parts go back that there is always one part that just baffles the mind.
I removed the earth lead from the battery and removed from the car. I just cannot work out where it bolts onto.

I would be grateful if someone can advise where these x2 eyes bolt onto . I am assuming the middle eye is on the bodywork while the end one is on the engine but where?

The remaining jobs to do are:
Fit earth lead.
Fit battery tray and relay - fuse boxes.
Replace both ball joints (ends of steering rack).
Adjust clutch.

Anyway here are some pics.

 

[frank]

starter motor bolt - chassis under the battery tray - battery iirc

 

[eiregti]

Earth strap bolts to the chasis leg beneath the battery tray somewhere and bolts to one of the bolts on the gearbox housing

Sent from my SM-G900F using Tapatalk

 

[Hairy Bobis]

Well I am very pleased to announce that I have now have a mobile Micra!!!

From the kind comments above I was able to fit the earth strap. One end was attached to the starter motor mounting bolt, the middle fitted under the battery tray attached by the screw bolt.

Once it was all connected up (front end still on axle stands) I started her up, selected first and lifted the clutch. The wheels started to rotate. I slowly selected second and as I lifted the clutch there was a grinding noise!!! A sense of panic and dread in the air (and a few choice words).

After I composed myself, I looked under the bonnet and tried to locate the noise and then it became apparent.

I noticed the offside driveshaft at the hub end was rotating in a circlular motion, it was not attached to the hub inside the cv boot. After 5 minutes of fumbling I got the shaft into the hub and all was ok. I must have inadvertantly pulled the shaft out of the hub when Iwas trying to get the shaft out of the old gearbox.

I have only driven her in first and reverse on the drive way and there are no leaks, so I am very happy.

The next stop will be the MOT.

A big thanks to those who kindly offered their assistance and guidance and a big thans to Matt for the gearbox.

Once I have put some miles on her I plan to get her lowered.

 

[Hairy Bobis]

I cannot believe how much time has passed since fitting this gearbox!

I just wanted to say that she got her MOT and is road legal, this week. It felt weird driving the Micra after over a year. I forgotten how eager the engine is especially as it is only a 1.0l. First time I have done a gearbox change and am feeling well pleased.

Now I need to get some miles on her to shake out any niggles and then swot up on the art of lowering.

Once again many thanks for your help.

PS. I must not forget to join the club!