Project Money Pit !

[Stirlingmoz]

Good point Mikey.

I do know that with the bearing removed, the helical gear is able to wobble on the shaft.

Assuming the gear is harder wearing (harder material) than the output shaft ?

 

[Stirlingmoz]

Spent some time yesterday afternoon rebuilding the gear selector mechanism.

Here’s the broken spring which wouldn’t allow it to select a gear



Where did the broken part of the spring go though ?

The inside of the gearbox was filthy but no sign of the missing spring leg ?

 

[Stirlingmoz]

Stripped, cleaned all components and rebuilt the output shaft onto a new shaft with a groove cut for a circlip.



Just waiting on some new bearings.

I don’t have a hydraulic press so I’ve just started to see if I can fab something out of a big old ‘G’’ clamp that with some spacers will allow me to press and compress gearbox parts on their respective shafts.
Thinking I can hold the ‘G’ clamp in the vice and gently wind bearings on and compress springs etc - it’s a work in progress.

Havn’t touched the input and intermediate shafts until I get the output shaft finished so I don’t risk mixing up any of the parts.

Gave the outside of the gearbox case another going over to clean and remove the silver paint.

It’s starting to look half decent.

 

[Mad Hatter]

Stripped, cleaned all components and rebuilt the output shaft onto a new shaft with a groove cut for a circlip.

View attachment 366410

Just waiting on some new bearings.

I don’t have a hydraulic press so I’ve just started to see if I can fab something out of a big old ‘G’’ clamp that with some spacers will allow me to press and compress gearbox parts on their respective shafts.
Thinking I can hold the ‘G’ clamp in the vice and gently wind bearings on and compress springs etc - it’s a work in progress.

Havn’t touched the input and intermediate shafts until I get the output shaft finished so I don’t risk mixing up any of the parts.

Gave the outside of the gearbox case another going over to clean and remove the silver paint.

It’s starting to look half decent.

Might just be the photo but it looks like there is some significant corrosion pitting on some of the gear teeth?

 

[Stirlingmoz]

The inside of the gearbox case was contaminated with water, thick oily sludge and polystyrene fragments when I finally managed to open it.

There is definitely surface corrosion on the gear teeth. I got the worst of it off. Nothing aggressive - just a cloth and WD40.

It will spend the remainder of its days swimming in fresh gear oil so my fingers are crossed

The oil baffles that were underneath the shafts are really rusted and will be replaced.

Weirdly the gears on the other shafts seem to have survived unscathed but I won’t know for sure until they’re disassembled and cleaned.

 

[Gelandestrasse]

Remember that shim only goes on one way…

 

[Stirlingmoz]

New bearings fitted to the output shaft and the lay shaft.

Shifter mechanism rebuilt / broken spring replaced.

I used a nicer set of shift forks than the set this box came with.

Reinstalled into the case to check it’s working



I put the plate on - not because I’m ready to measure up yet, but to steady everything while I check it’s working

Happy to report that it shifts into all gears.

Just the input shaft to go now. Got to fab a tool to enable me to compress the damper spring and release the clip. This will allow me access to the roller bearing inner.

 

[Stirlingmoz]

I found a cheap as chips rear wheel & tyre in the week, which means ‘Money pit’ is a roller

Wheeled him outside in the sunshine just to see where we are..








I also did that fateful thing and had a bit of a tot up. I reckon I’m about £1600 in, so far.

Still got some decent front calipers and brake lines to sell from when I first got the frame so that will help offset things.

Still quite a long way to go. I’m looking for a G/S front mudguard to replace the loosely fitted ST item in the photographs if anyone has any leads.

Finishing the gearbox is the next job, then I can move on to refurbing the top end of the engine.

 

[Mad Hatter]

Getting there

 

[Stirlingmoz]

Money pit moves into the garden room which has good lighting and heat. It means I can carry on work in the winter months.

Offered up a different front mudguard to channel his inner ‘super motard’ vibe.



Funny how a simple change can make a big difference. I quite like it.

 

[Stirlingmoz]

The gearbox is back in one big bit now.

Thanks to @Gelandestrasse for sending the shims I needed to get the required clearances.

Realised I don’t have an output shaft seal so can’t quite call it finished and install but v close



In contrast to this Hammerite silver painted filthy lump that wouldn’t shift gears and was full of watery oil and polystyrene

 

[Stirlingmoz]

Moved on to the left cylinder and piston.

The cylinder bore is clean with cross hatching still visible.

Another victim of the silver Hammerite paint - that’s got to be removed.

I will also replace the corroded push rod tubes.

Not done that job before - something new to attempt

 

[Stirlingmoz]

And the left side piston.

One of the rings was broken and it had the usual baked on filth on the piston crown.



Piston crown decoked and the ring grooves cleaned out.

New rings and circlips added to the parts order

 

[Kenny]

Moved on to the left cylinder and piston.

The cylinder bore is clean with cross hatching still visible.

Another victim of the silver Hammerite paint - that’s got to be removed.

I will also replace the corroded push rod tubes.

Not done that job before - something new to attempt

View attachment 378397

Don't forget to measure the length of each pushrod tube on removal Quality rebuild

 

[Stirlingmoz]

Fitted the rebuilt gearbox.



Only to find the neutral light switch isn’t working !

Work stops for the moment while I source another switch

 

[Gelandestrasse]

There's more than one reason for the neutral light switch not working. For this box the 'normally made' switch is used. Press it in and the circuit breaks. If it is pressed in all the while then you never get the light showing - which is the case if the switch is ok but screwed in too far. Use washers to position it so it functions with the gearbox change mechanism.

So remove it and test it before buying a new one? Forgive me if you already know this; only trying to help!

 

[kirby morgan]

Good advice Tim.
Also try a continuity test on the switch. It's a bit tricky to get to the 2 spades, but persevere. Once you put it into gear, there should be no buzzing from the meter. Neutral - buzzing. If that makes sense....

 

[Stirlingmoz]

Thanks for the tips guys.

I was sure this switch was working earlier or I wouldn’t have fitted it.

A soak in contact cleaner seems to have brought it back to life - at least for the moment.

Finished installing gearbox and airbox.



Need a clutch cable and a driveshaft gaiter next.

 

[Stirlingmoz]

Made a start on stripping the silver Hammerite paint from one of the cylinders this morning.

Horrible messy job



First pass. Needs one more go with the paint stripper I think.

Next weekend it’s in the oven to have a go at knocking the push rod tubes out so I can clean behind them.

 

[Stirlingmoz]

Bit of work on Money Pit this morning.

I’ve got the gearbox fully fitted now, airbox on, clutch cable in and adjusted.

Refitted monolever with new rubber gaiter and bolts etc.

Battery holder back in and everything electrical reconnected.

Had a little spin of the rear wheel to confirm all 5 gears are in there and it shifts quite nicely - neutral switch still working.