gearbox rebuild

[giorgio67]

HI Harry,

another good advice about the speedo nut...... thanks!!!!

NO OFFENCE PLEASE.....don't worry!!! also, you know how much respect I have for you and your job.

BY the way...if you can supply the full kit of brand new plated bolts/nuts/etc...it will be in my order..this is a kit I wouldn't be able to find anywhere..

Ciao

Giorgio

[giorgio67]

Hi friends,

just a little update.

As always no time for my car, anyway I have disassembled the two driveshaft housing.

I have built a "strange" homemade spanner for the job and it works well!!

Then, seeing that the cheaper 300mm extractor it's about 200 Euro I have bought two extractor legs and modified them with two holes for the fixing bolts on the extractor.

I need this to remove the inner race of the bearing on the shaft.

It work very well.

I have found a broken seal and the two retaining nuts in the housing completely un-torqued...(they must be 10 Kgm..)

The bearings (unavailable as original parts) seems good but...I HAVE FOUND THEM!!!! original and brand new!!! (thanks Mat), also I need to change the two seals and again...Ebay original Lotus at 10 Euro the pair..

That's all, some pics of the job and update soon of the rebuilding process.

Thanks guys for your attention

Ciao

Giorgio

homemade spanner

inner race on shaft

modified extractor

PS: I have also polished some transmission parts, now ready for the Nickel plated process

[simon a-b]

great pics georgio, very brave to be doing this but it looks like you're really on top of it!

cheers

simon

[giorgio67]

HI guys,

as always no time for my car..... but I'd like to show you my new system for the pinion depth measurement.

I had made a steel plate CNC machined with a 0.0000000000......tolerance , as you can see in the photos it will be the perfect base for the depth micrometer.

As Tim said me, could be a little tolerance in the machining of the bearing craddle so I will take the radius first and then the diameter with the bellhousing mounted to see the differences.

Then just some math..and I will have the perfect pinion depth measure......maybe

Now I'm waiting for your thoughts...and the Harry opinion...

Ciao

Giorgio

Edited May 31, 2009 by ghe67

[molemot]

I used a steel ruler, edge on, across the housing and measured down with a digital vernier caliper..took multiple measurements until I was satisfied with their consistency. Result has been working nicely since 1992...I'm sure your rig will be perfect!! If you haven't changed the crownwheel and pinion set, there should probably be no need to change the spacer..but best to check.

Edited May 31, 2009 by molemot

[giorgio67]

Hi guys,

little update of the work.

Finally received some new original parts (thanks Mat) so time to re-assemble the driveshaft housing.

new bearings and seals and my homemade spanner works great!!!

Some pics of the initial job, next week I will start with the pinion shaft assembly...

The fun begins!!

Cheers

Giorgio

.

[rydning]

Good that you do the work yourself.Its always fun to learn new stuff.

This input shaft look to be stronger than on the un1.And specialty the 5th gear.

So my gess is that this box is stronger when in the 5th.

[yeller77]

Giorgio, great work. While you have the 'box in pieces, you might think of having the gears, shafts REM treated. You might try:

R

[giorgio67]

Hi Eric,

thanks for the info.

Very interesting but I don't think to use that service. I know for sure that if used well the C35 gearbox is a strong unit, and the power/torque of my engine will be less of the turbo model.

I'm replacing all the 8 bearings, the synchro rings and some gears too, so my box will be as new.

Anyway, it could be interesting for other parts in the future.

Ciao

Giorgio

[giorgio67]

HI,

just finished to rebuild my driveshaft housings.

Shaft pressed on easily with a big extractor, works great.

Very good job, just some pics of the finished work.

Cheers

Giorgio

Edited June 8, 2009 by ghe67

[Mieczkowski]

You are an inspiration! Great work and I appreciate all the pictures, Giorgio..

Tom Mieczkowski

89 Esprit

St. Petersburg, FL

[molemot]

You didn't buy a car, did you Giorgio? Just a box of bits to play with!!! Have fun....and we're all looking forawrd to the end result!!

[giorgio67]

John,

my car was perfectly running when I bought it.....with a new MOT!!!!!

But I'M REALLY MANIAC so my goal is not to be driving a Lotus esprit but one of the best S2.2 in the world!!

Anyway I must admit that I'm loosing so much time on details that sometimes I'm thinking....well, I will never see the end....

No....I'm joking...I think my job are on the right way, it's just a question of economic!!!

Ciao

Giorgio

[giorgio67]

Hi guys,

just received some new parts from Harry (thanks mate) so new satellites/planetary gears installed.

New CWP bearings and I'm ready for the bearing preload procedure but.....the previous owner/mechanic has stripped all the 7mm threads of the driveshaft housing bolts....I have found badly inserted helicoid in every hole...now time to modify all the threads with 8mm bolts.

I'd like to know who has been servicing the gearbox in this way.... :)

Some pics of the job.

Update in the next.

Cheers

Giorgio

Job done!!

Edited June 24, 2009 by ghe67

[giorgio67]

HI guys, update....

Just finished to re-assemble the pinion shaft with new parts.

Brand new 1

[giorgio67]

HI guys, update

Pinion depth setting done, I have ordered twice the right shim...but the tolerance now is 0,02 as stated on the manual, good.

Then, I have tested the synchros on the primary shaft before fitting it, and again everything was good, so I Have fitted the shaft with all the gears in the casing with the pinion shaft already fitted...not an easy job... (a chinese puzzle) but after some bad words...everything was fine.

The hard thing is to fit the circlip on the shaft once in the gearbox, very time consuming....for me.... but again great satisfaction.

Beautiful!!!! front and rear bearing fitted, and all the assembly ready for the backlash procedure.

Oh my god...I'm stupid..?

I've forgotten to fit the 1

Edited August 23, 2009 by ghe67

[Jeanvm]

Hi Giorgio,

Thanks for your time consuming documentary work. But I am not so sure that I would be able to do the same thing.

Cheers,

Jean

[lotusvette]

hi, its a daunting job at first, but pretty straight forward when you get into it, got my parts from brodie , price of parts are frightening, thank god gear teeth were ok ,its nothing that cant be done at home

[andydclements]

At age 16 I purchased a 50cc moped in boxes, then found there was no such thing as a workshop manual for it (it was a current Yamaha model at the time), so had to purchase a manual for a sister model and use that for the engine. i had to re-build it, run it then diagnose the fault it was originally taken apart for (diagnosed by Yamaha service agent as drive shaft) and then find it was piston ring and bore wear and correct that. I've taken countless engines to bits ad re-built them, but never have I taken a gearbox to bits more than one end casing or the output shaft area, then it was just quick check for obvious wear, and close it up thinking "I'm not going to lok any further, I'll never get it back together"

Giorgio, I take my hat off to you!

[giorgio67]

Hi guys, thanks for your comments.

I must say that this has been one of the most interesting mechanical work I've done.

Yes, it's not so complicate once you are inside, the difficoult is symply to doing it like it must be done...

The difference from a properly rebuilt and just a re-assembled box is a matter of thousands of millimeters in many parts of the assembly, that's it.

Patience. special tools, and the Harry's help has been fundamental in my job, there are a lot of tips not reported on the lotus manual and there are secrets that only a men working for a life on these parts knows.

Ciao

Giorgio

[giorgio67]

Hi friends,

just finished to re-assemble the 5

[molemot]

I rebuilt my gearbox (new CWP and 1st/2nd synchros) back in 1989..iirc...in the garden, on the concrete slab outside my parents' kitchen, hiding the bits under a tarpaulin when not being worked on. 20 years later, still going nicely (hope that's not tempting providence!) but never as shiny as yours...!

When will you put some POWER through it? You know....in a CAR?!!!!

Edited September 12, 2009 by molemot

[giorgio67]

Hi Buddsy,

thanks to appreciate my job.

Best sealant you can use is the Loctite 518, suitable for all the alloy mating faces.

Remember to put new driveshaft housing gaskets and don't use any sealant in the bearings house, the bellohousing mating faces.

Ciao

Giorgio

[giorgio67]

Hi friends,

still some works on my gearbox...

just received my brand new and improved input shaft spring & improved circlip from Harry.

Fitting has been a little complicated but finally everything good.

I have already assembled the bellhousing parts and now time to put the end word... on the story.

Next week chassis paint and time to reassemble all my suspension parts.

The engine is waiting on the crane...winter job.

Ciao

Giorgio

spring in position

[giorgio67]

Hi mate,

thanks for reading my topic!

Yes, new driveshaft housing gasket and Loctite 518 on all the metal mating faces, bellhousing too.

Let me know how you proceed with your box.

Ciao

Giorgio