Esprit Turbo project car - part3 - the further continuation

[Lotusfab]

The irony is rebuilding the diffs is more trouble than the gearbox! 

[Lotusfab]

I would rush output and buy the triump gearbox bit yet as I have to confirm it fits and the shaft can pass through it!

[910Esprit]

There you go....  I make it closer to 45 than 44, as you can also see I use a 1 3/4 box spanner.  The outside of the hex portion is a snug fit in the retaining ring, hence it undoes both in a single operation....   Happy to loan it to you Fabian if you get stuck

[Lotusfab]

Spookily here's the 1 3/4 one I ordered earlier today....

Thanks for the offer, I hope this will work.

[Lotusfab]

I won't be posting any detailed gearbox rebuild info. I'm not a gearbox builder and intend to stick to what it says in the manual. I suggest asking an expert on here such as Harry Martens if you need any more info than it states in the manual. I will post tool solutions, as this is the awkward bit. All I can say is it is easy to dismantle, once you have the correct tools.   

So you can buy the speedo nut spanner for £10, which works a treat. You may also need a puller, spring balance, dial guage and engineers straight edge. In addition the 1 3/4 socket and a ring spanner. They must be able to be torqued. In order to achieve this I will post tool pics when I have solved the issues.

[Lotusfab]

A big part of this is cleaning. I have gone through most of it with parts cleaner, but it's all off to the aqua blasters as well. 

[Lotusfab]

There's something missing!

[Lotusfab]

Tips not in manual

The blanking plugs for the interlock plungers are made of metal like small core plugs. I punched a hole in the centre and plunged them out. You have to take both sides out to push the plungers out.

The ball and springs for the selector shafts mentioned in the manual are under the shafts in the holes at the end of the box. When you pull the shaft out the ball flies out! Rotating the shaft to remove the ball from the shaft detent helps.

Now I just have to find the ball that flung off! 

 

[Lotusfab]

I'm now looking into what to replace. Seems to me without the Lotus tool the setting of the pinion height will be difficult. So Andy gave me an idea of using engineering blue. I think I might look at going down this route. Here's some examples of the system. 

 

 

[910Esprit]

Its probably  a good idea, but the problem you will have is that the case does not secure the crown wheel with clamps, the clamps form part of the bellhousing which in turn control the preload and crownwheel offset by the use of shims located by the driveshaft housings, so you will be doing a fair bit of assembly/reassembly - not to mention the shimming of the pinion in the first place!   But we know you enjoy such challenges....   

Edited March 26, 2019 by 910Esprit

[Andyww]

Another factor with these boxes are they are running backwards, so nothing will ever be 100% right. As Harry M would confirm, the main reason for CWP break-up is the teeth are mating on the wrong sides.

Mating on the wrong side is never good

They also pump oil out of the speedo drive instead of onto 5th gear

 

[Lotusfab]

2 hours ago, 910Esprit said:

Its probably  a good idea, but the problem you will have is that the case does not secure the crown wheel with clamps, the clamps form part of the bellhousing which in turn control the preload and crownwheel offset by the use of shims located by the driveshaft housings, so you will be doing a fair bit of assembly/reassembly - not to mention the shimming of the pinion in the first place!   But we know you enjoy such challenges....   

Im in an odd situation. Some one has rebuilt this before. The Primary shaft front bearing is new and some if the others look new. A new third gear and the shims will stay the same. I was going to clamp the diff like this. So I can blue the wheel, check the preload with half the case off and see where the teeth contact. Then bolt the other half on to check the backlash. All theoretical up to this point. Once Inhave a go it might be a non starter. Still this job is ok so far. Just need to sort some parts. Like the speedo gear, which the tab broke off and a third gear! Then one needle bearing and it's going back together!

The half shafts are more tricky, due these tools. I have dismantled one partially. Just the bearing half to get off the shaft. Then I need more tools. The great thing is all these jobs will be easy next time and I'll have the tools! 

[Lotusfab]

Ohh, have to say the half shaft nut and ring nut were pretty loose. There is no way they were torqued up correctly. Probably the previous owner didn't have the correct tools. 108 lb ft on the nut and 72 lb ft on the ring nut is quite a lot. It will need a proper tool to reach these levels. At least it's not a Landrover discovery, then we would be talking torques of 200 lb ft upwards! 

[Choppa]

3 hours ago, Andyww said:

 As Harry M would confirm, the main reason for CWP break-up is the teeth are mating on the wrong sides.

 

HML has had a batch made that run the wrong way round so when fitted to our gearboxes the  CWP teeth mate on the correct side!

[Lotusfab]

Ohhhhhh dear!

it wasn't me, I wasn't there, I didn't touch anything, he did it! Now what am I going to do. Like a manager told me in a well known exhaust and tyre fitters once when my chasis needed a £15 welding job, your chassis is F...d mate. Might as well scrap it! 

Now who is going to contact me with this part first?👍🏻

[Lotusfab]

Ok half shaft almost there had to cut out oil seal. My 25Tonne puller is too large to fit. So will have to get another. Like all thing Lotus a special tool is needed! Won't fit my press either!

[snowrx]

Just TIG weld the tab back on?

[Lotusfab]

That bit is an oil strainer. The tabs locate it in the gearbox case with not much load. It could be welded, but happily I have found another one. 

I have located some damage in the gearbox casing. It has been repaired and is only on one side. It's only in the inside surface. It looks like its was caused by disintegration of the the diff. That would explain why the diff and pinion look new! I believe they were replaced with most if the bearings, maybe this is the reason this car was taken off the road about 15 years ago!

The Gearbox is very straightforward so far and is interesting. I have the outer casings away for aqua blasting. I'm painting the main case, as I don't want any glass beads in there. Although I believe the pinion bearing is new there's no point taking a chance. I have decided to replace it. A new speedo nut and third gear with a lot of cleaning and it's all going back together soon.

I have managed to source a replacement half shaft, so I can discontinue the rebuild of these.

[910Esprit]

Not exactly a 'strainer' thats the oil 'seal'  for the input shaft, the scroll caches oil and drops it back into the diff housing via the tube

[Lotusfab]

Better description!

[snowrx]

Critters got loose in my differential  case as well.  A story the prior owner did not tell.....

[Andyww]

Things were so much simpler back in childhood days of building differentials out of Meccano! I still have all my Meccano gears!

[Lotusfab]

8 hours ago, snowrx said:

Critters got loose in my differential  case as well.  A story the prior owner did not tell.....

Similar to mine.

The best thing about it is my car now has what appears to be a new crown wheel and pinion! 

[Lotusfab]

Thus is his I found it, no cleaning!

[Lotusfab]

Months later, the gear lever is sorted! Now the fun of installing it!