Left Hand Cover.

[Mark]

Another conundrum.
Just when I was almost ready to fire it up - isn’t it always like that!

Stripped thread in the left side cover where the oil pressure sensor screws in.

The book says remove the clutch and ignition before removing the cover.

This was a rusty wreck but the clutch works fine so I only just found out the retaining nuts are rusted on solid. Any ideas?

Options, once I source the special tools and find a way to take the clutch plates out are, I guess, a helicoil or another cover.

This is a 1983 K1 - if I look for a s/h cover am I looking for any cover or are there variations (apart from the later model rev counter drive which I think doesn’t change the actual cover shape?)

Any ideas appreciated - Ta.

[mbmm350s]

Hi Mark

Is there really no way you could fix it externally. With Helicoil?
I wouldn't care about the oil pressure sensor, earlier 350s never had it.
So I think any 350 up to and including K1 would do.

When the clutch spring nuts are seized you need to take great care not to release the studs
from the clutch centre this can damage the centre badly.
Lots of soaking with release fluid, heat, patience and do try to tighten first a little.
When re-fitting i tighten them down and back off a little so this doesn't happen

The manual shows how to make the clutch screw tool.

When the engine is in the frame you don`t need the clutch holding tool, put in gear and hold brake,
(or use an impact wrench)

Mark

[P.I. Staker]

If you know a friendly plumber or have access to a lead burning/welding kit. This seems to work very well, by applying high localised heat to the nuts to the point of getting them cherry red in colour. Every one on my bike came off without a problem and it had been standing in a leaking shed for years.

[3potjohn]

So the oil pressure switch needs fixing which will require an insert. Getting to it means clutch removal, drain oil, inner cover off etc but the clutch nuts are stuck which is worse.You must get the clutch out so take care and try releasing fluid for a few days in the first instance. What you do not want is for the studs to turn in the clutch instead of the nuts coming undone. Others have reported similar so you can take solace in this.
Good luck
John

[Mark]

Thanks for all the ideas everybody, especially for the note about the danger of turning the studs instead.
I shall plod on, slowly.
Cheers, Mark.

[72degrees]

The manual shows how to make the clutch screw tool.

When the engine is in the frame you don`t need the clutch holding tool, put in gear and hold brake,
(or use an impact wrench)

Mark

I've found the 'slotted screwdriver) ones sold for old British bikes (BSA/Triumph) work quite well. The real fix is a set of the excellent hex head spring nuts that Weevee used to sell, not sure if available from Mdina. I made a holding tool from an old plain plate and a length of steel bar. The 'universal' clutch holding tools are also quite good. I finally acquired one when doing the recalcitrant clutch on the 1957 Gilera 175. That had two seized spring nuts which had loosened the studs in the centre. I had to drill one out and ruined the stud, but fortunately I found a used replacement hub on Ebay.it, which interestingly used a completely different and superior stud arrangement. On Morini machines with cast wheels a length of 2x4 betwixt wheel 'spoke' and swing arm can make the gymnastics easier

[3potjohn]

Having a good fitting tool would be ideal.I have made a slotted tool out of flat steel but if I had some rod or tubing I would try and improve things, with my very limited tools. No room for a lathe and I am certain I could not get away with one in a spare bedroom.

[mbmm350s]

If you want to buy a clutch holding tool I can recommend Tim Ralph.
http://www.ralphrestorations.co.uk/view.asp?g=686
Mark

[julianharty]

I spent weeks working to free up seized clutch spring nuts for a Kanguro that had been standing for 15+ years. In mine there was extensive rust and just about every problem to surmount. In short I managed to remove all bar one nut by making a special tool (roughly as per the dimensions in the blue book), this was after weeks of repeated use of plusgas, heat, etc. The last one the shaft started spinning in the clutch center and I ended up bending a 9mm open-ended spanner into a sort of Z shape so it'd fit through one of the other 4 holes (where I'd managed to remove the clutch spring nut) to hold the shaft in order to turn the nut with the special tool.

The special tool I created used an impact driver flathead where I cut out the centre using an angle grinder. I'll attach a photo when the forum lets me.

Have you thought about replacing the damaged thread with a helicoil or other thread insert? I appreciate you'll need to remove all the debris that the drilling and thread cutting would cause to prevent it from blocking up oilways.

[norbert]

Before taking the risk of loosening the studs if the nuts resists, I prefer to destroy the bend of the cup of the spring with a flex o dremel. Then you can get the plates and the center of the clutch out. Then its more easy trying to get the nut off contering the stud. Especially if it is one of the old ones centers that have hexagonal studs. Its quiete easier to find such a cup than a center in good condition

[julianharty]

Destroying the cups may help to remove the clutch; however if the studs are loose (insufficiently fixed to resist turning) in the clutch centre, they'll still be loose and need securing.

To that end, partly as an experiment, I've had a go at TIG brazing my rotating stud yesterday (Sunday). I'm aware other approaches are possible and some may be better than the one I used, I had read about this approach and it seemed both interesting and potentially viable.

At this stage I don't know whether it'll a) hold sufficiently longer term (it seems fine currently) or b) whether the heat from the TIG (needed to melt the brazing rod) would have any long-term adverse effects on the clutch centre or the studs. I've taken photos; currently I'm still reducing down and smoothing the brazing.

BTW: I'll probably start a separate forum topic about the clutch repair at some point so it's easier to find in future than here.

[3potjohn]

I usually find if a nut or bolt won’t undo it will be the last one in the sequence.Any joy yet?
John

[julianharty]

John, if it wasn't the last nut you encountered, it'll probably be the last one you undo!

Thank you for cheering me up

[mbmm350s]

Hi John

You forgot to say its always the one most difficult to get to
Mark