gearbox rebuild

[giorgio67]

HI guys,

As you know I'm restoring my lotus esprit S2.2.

I was planning in the past to send my gearbox "like it is" to Harry Martens for a rebuild....

But...my interest in the mechanical and technical parts of my "babe" is really so strong that I have take the MAD and hard decision to do the job on my own.

After a long search i have found a brand new CWP sincros and bearings at incredible prices so, as I need to save money it's now time to dismantle and see what I can do...

I have studied the gearbox section on the manual but I'd like to know if there are special tips regarding the rebuilding procedure as I have not any experiences in gearbox job.

If I remember well Tim Engel said that it's the right box for a novice even if I think it's quite an hard job to do.

I'm aware about the special tools required but again Tim will be able to help me...I hope

If there is some member with some experience about that I will be grateful to know everything from his skill.

I don't want to end with a box full of gears and parts....

Thanks in advance.

Cheers

Giorgio

[freshcut]

I've not disassembled a Lotus gearbox, but in my youth (I'm guessing I was about 14 at the time) I did disassemble the gearbox in an old Datsun my mother had. Having never seen the inside of a gearbox before and with only the help of a poor exploded view in a $10 chilton book was able to disassemble the box, replace all the ball bearing assemblies and synchros, reassemble and reinstall the box. Worked beautifully afterwards. My suggestion is to be patient, make sure that you look at the diagram and compare what you see in the diagram to what you're seeing in the gearbox yourself. Pictures would definately be a big plus and with digital cams now, it's much easier to referrence back to what you took a shot of a few minutes prior if you have any questions about a certain sequence.

I would have to say that the nice thing about any gearbox disassembly and reassembly is that it's very easy to ensure that everything will work when reassembled since you can turn the input shaft, switch through gears and listen or feel for anything that feels "off". Much easier than an automatic that requires hydraulic pressure to operate.

Personally, I think a gearbox teardown and rebuild is a good begining for someone who wants to get into a more complex technical repair since it involves a lot of pieces that need to work together, but is simple enough that someone who's observant can read a diagram and has even minor mechanical knowledge should have little difficulting accomplishing.

[ramjet]

Giorgio,

I have done several gearboxes for a previous employer and did not have manuals. Got the tolerances required for certain parts from the vehicle manufacturer and simply slid each part onto a length of string as I disassembled the various shafts. Easy to keep things in order that way. To reassemble, take part off the length of sting and put back onto the relevant shaft. Take your time and as Blake said, take pics and make notes as you disassemble.

Michael.

[matk]

I like the idea of the string, one of those useful ideas that you never think of yourself, but seems so obvious after you hear it!

[ramjet]

Lot's of things work Mat. Lengths of wood dowel etc. Dowel is good as it is easy to move assemblies of parts out of the way easily.

[giorgio67]

HI guys,

no time to waiste here.....

Just some pics of the initial dismantling.

For what I have seen the CWP are in brand new conditions and all the internals seem very very good to me.

So, my idea is to replace the driveshaft bearings and the CWP bearings as well, and also the front pinion bearing and 1

[giorgio67]

Buddsy,

thanks...

I don't know if I am mad or brave...but maniac for sure!!!!

Anyway, sincerely I have not experiences in gearbox rebuild and you would find better advices instead of mine..but I suggest to do a careful inspection of the internals after degrease all the gears.

Worn teeth or badly consumed gears are signs of something wrong.

Take a look in the bottom of the box to see if there are any signs of metal...no good and then check your ball bearings and CWP rotating the driveshaft and listen for noise and strange crunkling.

In the S2 esprit I would change anyway the driveshaft bearings as the shafts are stressed due of missing of the suspension arms ...but the S3 like your has a different chassis and suspension design so, for what I know they don't suffer to much in that area.

I will update soon.

Ciao

Giorgio

Edited January 15, 2009 by ghe67

[dsvitesse1]

Hello,

diff.carrier bearing 30208 SKF standard bearing

rearbearing for pinionshaft is not standard. Inner diameter is 41 mm instead of 40 mm for the standard rollerbearing.

Got all the parts or advice if you might need anything.

good luck,

Harry Martens

[giorgio67]

Harry,

thanks!!!

I will contact you for further advices or to send you a box full of parts and gears.......

BTW, can you supply to me the bearings for the driveshaft housing?

Thanks again.

Cheers

Giorgio

Edited January 15, 2009 by ghe67

[dsvitesse1]

sorry Giorgio, I only have the complete diff.carrier housing complete rebuild with new ( other ) bearing and seal.

Original bearing is not available.

cheers,

harry

[910Esprit]

My advice would be 'if its not broke, don't fix it' - Too late for you Georgio!

The actual gearbox seems a very robust long lived unit. Mine's still sweet as a nut at 100,000. Although the CWP can fail, I reckon its generally due to wear in the (fairly easily replaceable) diff carrier bearings - not due to the power of the cars.

cheers Steve

[giorgio67]

Does anyone know the size of the big nut retaining the bearing on the driveshaft housing?

On the Citroen DS parts list it's described as 30 x 150...so must be 46 mm wrench?

Thanks

Giorgio

[dsvitesse1]

Correct!

salut,

harry martens

Edited January 23, 2009 by USAndretti42
Removed quote

[giorgio67]

HI guys,

update of the rebuilding.

I have made the special wrench to remove the gear nut of the speedo...(thanks Tim for your help).

Everything has been easy and very interesting and the gearbox now is fully dismantled and I'm ready to checking carefully every parts.

I put some pics of the job.

Next time I will show you the new parts ready to re-assemble.

Ciao

Giorgio

Edited January 30, 2009 by ghe67

[giorgio67]

this is the spacer for the pinion setting

finished job

[molemot]

I rebuilt my gearbox after the crownwheel and pinion shed teeth, and I remember that spacer..it's selected by thickness to set the pinion projection and thus the correct mesh of the pinion and crownwheel, which come as a matched pair, with the required pinion projection engraved on them. This has to be measured by either a special rig, or a bit of ingenuity...anyway, having decided the thickness needed, I ordered the correct spacer from a Lotus main dealer..who sent me the wrong one. So I went to see them; seems they had sold quite a few crownwheel and pinion sets, but mine was the first spacer they had ever been asked for..makes one wonder!! Got the right thickness in the end, and the box has been fine since 1992.

[Paul Coleman]

You're a braver man than me Giorgio good luck with it.

I got the urge to go and work on my car the other week but it soon passed

Cheers, Paul.

[giorgio67]

Hi,

while I'm waiting for some new parts I have polished the gearbox housing just to see if it can be good without painting it.

I'm really satisfied with the result.

It looks shine!!!!!

Cheers

[Jeanvm]

Good documentary Giorgio,

Next time when needed I can overhaul mine box with your help.

Thanks,

Jean

[Paul Coleman]

Looks good Giorgio what did you use to clean/polish it?

Cheers, Paul.

[giorgio67]

HI Paul,

I have put the gearbox on the washing machine...... and then just a polish compound and a brass wire brush on a drill.

I will finish with some coats of clear laquer for alloy.

I don't like the silver paint on gearbox/engine, i prefer the original finish.

Ciao

Giorgio

[giorgio67]

HI,

I have dismantled the pinion bearing to check the conditions and to measure it but I have found a part not reported on the Parts list..

On the bottom face of the bearing (not the pinion side) there is a washer and I can't recognize what it is.

The bearing is the correct 41x80x18 and the thickness of the washer is 3mm so the total thickness of the bearing is 21mm.

Any suggestion?

Maybe Harry will be able to answer me...

Thanks

Giorgio

[dsvitesse1]

Hello Giorgio,, yes I can answer your question. It's a part of the bearing. The bearing is an NUP type rollerbearing.

However, sad for me you only want advice/information from me and have another source for the parts..

good luck,

Harry Martens

www.ds-vitesse.com

[giorgio67]

Harry,

first of all thanks again for the info.

That said, it's not true what you said, as I have not any other source for the parts.

I have ask you in the past days some prices about some parts I need, because I didn't know if they are expensive or cheap parts.

The question is really simple, I have not money at the moment to spend in my car...so I'm trying to find what I need on ebay and from some dealers of my town.

Yesterday for example I have forgot to bid on the rear pinion bearing on ebay (original Citroen parts) and it has been sold for 67 euro......so I don't like to pay the same part 200 euro...I can't !!!

As you know the same gearbox was used on a Citroen van and also on a FIAT van, I'm living in the Fiat town so I have a lot of specialist and suppliers here, and as I have told you I have found brand new CWP at 200 euro, syncro ring and needle bearings at 15 euro each...

I need still some parts and if I will not able to find them at cheaper price be sure I will place an order from you.

I don't want to be boring regarding the infos as I know this is your job and you have your secrets...but this is a forum and I think it will be good from all of us to know as much as possible about our cars.

Regards

Giorgio

Edited February 3, 2009 by ghe67

[dsvitesse1]

Ok Giorgio I understand now. I was reading on this topic that you were waiting for some new parts so I thought had another supplier. I wasn't aware of the fact that you are in a Fiat town.

200 Euro for a brandnew CWP is really, really nice. Congrats for that. Please check the thread for the speedonut. I'ts different. You mustr grind it down and make the right thread.

Anyway, good luck with the rebuild and the search for original parts.

no offence please,

cheers,

Harry