Jupiter restorations.

[Srenner]

Berkeley. Good luck finding one!

[David Kemp]

How do you get the brass speedo drive off the main shaft of the gearbox?

[Keith Clements]

It will come off when you pull the bearing off the shaft. Taking it off without doing that would be close to impossible.
I have made a bearing puller to do the task.
The circlip is taken off the bearing outer casing and the puller is clamped into the groove with a Jubilee clip around the outside.

[Srenner]

Here's my wonky set-up for pulling bearings. Four lengths of threaded rod, nuts, a big bolt/nut, some thick scrap steel and two gigantic washers I bought at a home improvement center. Drilled holes for the rods, cut one of the washers in half and used a grinder to thin it to fit in the bearing groove. Welded big nut in place, but it could work with everything bolted in place. Used a jubilee clamp at the bearing end to hold the washer into the bearing. Only recently welded the nuts in place to act as the clamping force as it's a lot less wobbly. Used to use the threads to adjust the distances front to rear, but now use a length of scrap rods cut to length; much, much faster. Cut a notch to clear the layshaft protrusion at rear. I do remove all the studs to gain room.

[David Kemp]

Thank you, I have made a dodgy puller , that managed to remove the front bearing.
However seeing yours I am going to upgrade, as mine was held together with wire, which is not the best.

[Srenner]

Forgot to mention bottom holes are tapped for the rods as need to sit flush. Good luck. Also, nice to see one dodgier than mine!

[David Kemp]

after looking at yours , I have made puller number 3.5. puller number 4 will be better once I can get out & find better steel.

[David Kemp]

How do I identify what gearboxes I have? The only markings are pictured below. Aso note the worn layshaft.

[Srenner]

Meadows. Jowett boxes start with a "J". If you get deeper into the box, Meadows scribed the part numbers on many of the parts. Jowett did not. IMHO, the quality of the machine work looks smoother and better finished on Meadows gears. On the other hand, slightly more efficient gaps between gear ratios on the later Jowett box.

[David Kemp]

Do you have a photo of jowett
Gearbox markings? As i would think the odds of both of mine being Meadows would be unlikely.

[David Kemp]

Ok after cleaning the internals , my parts are engraved with part numbers & the layshaft gear has 34 teeth.
From this I deduce the 1st box I have is Meadows close ratio box. If I am wrong please correct me, as others will need to know for the future.
So far one of the straight cut gears has a small chip in it the others look good.
The layshaft is worn & the main bearings are slightly worn.
Has anyone found a way to seal the spigot shaft better than the Jowett way?

[Keith Clements]

There are different ways to improve on the oil spinner arrangement. Perhaps have a search of JowettTalk , I think they are documented.
On a couple of mine I fitted an oil seal but that was in the 1980s.
The tech notes contain a few pages on curing gearbox oil leaks.

[David Kemp]

Thanks, I found the article on fixing gearbox leaks very useful.
Looking at my two selector covers, though both Meadows they are different.
Are they interchangeable ? Is one design better than the other?

[Keith Clements]

I would have thought the later one was better. Figure that out if you know which case it came from. If it has same part number then it is probably interchangeable.

[Nick Webster]

Ok after cleaning the internals , my parts are engraved with part numbers & the layshaft gear has 34 teeth.
From this I deduce the 1st box I have is Meadows close ratio box. If I am wrong please correct me, as others will need to know for the future.

It was always my understanding that the Jowett box was called the close ratio box and the Meadows the wide ratio.

Nick