Lotus 5 Speed: Input shaft removal special tool

[mbell]

Hi,

I need to pull the input/1st motion shaft from my gearbox to replace 4th gear synchro ring. Reading the manual the assembly should just pull out. However a couple of special tools are required:
1) 18G284AAC/2 - A spacer that slides between 4th gear and the bearing outer race. So when pull the force is transmitted to the outer race.
2) Various spacer/adapters to connect a slide hammer to the shaft

I am wonder if what people have done for these when working on these boxes? Not impossible for me to figure something out but suspect others have already done this and figured out better solutions, especially for 1.

Thanks,

Mark

[mbell]

So today I test drove the car after fixing this.

In the end I made my own tools for this. For 1) I used some 2.6mm steel sheet to make a two piece tool, one spreader and curved piece. The curved piece is ~18.5mm with ears added to hold it in place.

1) tools

1) in box

For 2, I used some 1 1/4" x4" threaded pipe and caps. I drilled out the caps, one to go over shaft and one to connect to slide hammer. Then a couple of washer were filled and cut in half to engage the on the input shaft.

Shaft puller

On box

Reading the manual the assembly should just pull out.

I was wrong on this. The fourth gear/dogs foul on the lay gear. So that has to be dropped, which means removing 5th gear, half removing reverse and removing the lay shaft. So it's quite a big job.

[nmauduit]

thank you for sharing, the Lotus 5 speed is not much discussed, and making up special tools is more often than not a prerequisite to get going...
so how did the repair work out in the end (if there's an end)?

[mbell]

so how did the repair work out in the end (if there's an end)?

Only done a few quick miles around the neighborhood but it seems to have worked out well (so far...). All the gears are working, no strange noises and can select 4th when warm without double de clutching now.

I am reasonably confident I've sorted the leak that triggered the work. This was a leak on the out flange, with oil working out down the shaft, through the pinion and under the nut. Then exiting via the flange joint. I've put some thread sealer on the pinion and nut. Then also sealant on the output and prop flanges. It will take much longer driver to confirm the leak is fixed thou.

I ended up stripping the box about half way down to to do the 4th gear synchro. Went reasonably well but did have a few issues:
1) 5th gear fork grub screw snapped on removal. Put very low amount of effort on the locking nut and it snapped off. Luckily got the remains out easily enough. It is pointed type and exact replacement not available, had to use one with different angle tip, but should work ok.
2) 4th gear synchro needed adjustment. Luckily after fitting I tested selecting 4th and it wouldn't engage. Turned out the outer "hump" sections of the new synchro rings were fouling, so had to remove input shaft and file them down before refitting.
3) Bind of Layshaft when torqued down. I didn't quite getting the bearings in the right position and this triggered some binding when I torqued the layshaft nuts down.This was sorted by a bit of "adjustment" of the rear bearing position.

I now have a lot of random pictures of the inside of a 5 speed gearbox in different states of dis-assembly.

[Rdracer]

Hi There,I read M Bell's post with interest,as I am not given to getting involved on here.I too however have had to learn through bitter experience how to rebuild the 5 speed box.As I am nearing the end of a full restoration on a genuine Sprint 5 with gearbox no 8 in the series(very early),and have encountered some of the same problems.Also the supposed "experts" were either not very willing or unable to give any advice.I too like M Bell have a complete photographic rebuild of my gearbox, which may help some people.I needed to make a holder for the 3rd motion shaft,when it is during the reassembly stage,a dummy bearing holder for the front layshaft bearing as well.I started off with a slide hammer for the input (1st motion shaft) removal,but have since modified this to a screwed tool,which pushes off the front of the casing,as it is more controlable,and less harsh,on what is a very fragile casting.I also encountered many problems regarding poor and incorrect parts supply,and on first assembly my gearbox locked up,as M Bell correctly states,the new baulk rings need to be ground down,as they do not pass through the synchroniser hubs.I informed the parts supplier,but they were not interested.There are many other pitfalls in building these gearboxes too,and its a journey of learning to get them to work properly.I will be making a new input shaft remover for my next 5 speed gearbox on another Sprint .I will try to post some photos if anyone is interested,but technology is NOT my strong point.
Roy

[mbell]

I will try to post some photos if anyone is interested,but technology is NOT my strong point.

Thanks for the post, I certainly find it interesting and likey useful for others.

I informed the parts supplier,but they were not interested.

I didn't even bother in the end as expected I'd get that response. I suspect there isn't much option in part producers for theses so you get what you get.....