Cota 247 kick start

[oldaz]

As part of the rebuild on my 247 I had to split the engine cases to replace some bearings, bushes and seals. In the process I noticed the kick start shaft has about 4mm end float. When I looked inside I found the spigot on the inside end of the shaft only goes about halfway into the inner bush and there's a 4mm thick spacer washer on the spigot which prevents the shaft going all the way into the bush. Secondly the starter gear is only partially meshing and looks like it needs to go at least 3mm deeper into mesh. At the other end of the shaft there's a circlip to hold the ratchet mechanism, but no thrust washer between the circlip and the bush. All this suggests to me there should be a spacer washer on each end - about 1.5mm thick on the spigot end and about 3mm thick on the lever end. This would eliminate the end float, set the spigot deeper into the inner bush, line up the gears and prevent the circlip bearing against the lever end bush.

When I look at the parts manual it shows 2165.115 as the spigot end spacer and 0265.118 as the lever end spacer. Mine doesn't have the lever end spacer washer and the spigot end spacer is 4mm thick.

Does anyone know what thickness the spacers are supposed to be? TIA

[bigshineybike]

When I first got my 348 the previous own had lost a handful of spacers from all parts of the engine and gearbox. The only excuse i could make up for him was that at some time in the past 40 years the engine had lain in  bits for a few years and when it was put back together pre internet there was n way to get hands on a manual. There are racists out there probably thought the bloody Spanish don't know 'owt about engines and they're all  rubbish. 

Nowadays we know better. You may be able to find a bucket of spare spacers eventually but in my case I measured everything and made up new spacers and shims .Do bear in mind there is a requirement to shim endfloat albeit within fairly loose limits. I have a few spare engines in bits but they also are missing all the useful spacers and shims.Sorry this isn't much real help.

But be assured many of us share your pain.

[oldaz]

28 minutes ago, bigshineybike said:

Do bear in mind there is a requirement to shim endfloat albeit within fairly loose limits. I have a few spare engines in bits but they also are missing all the useful spacers and shims.Sorry this isn't much real help.

But be assured many of us share your pain

Thanks for letting me know that many of us share the same problem, lol.

I've decided half to one mm end float has to be better than 4mm and having the spigot go 3/4 into the bush has to be better than half way. By using a thinner spigot end spacer of 1.25 instead of 4.25 it's allowed the kick start gear to line up with full tooth contact, so should also be better/stronger. Fitting a 3mm spacer to the lever end of the shaft (still inside the cases) has reduced the end float to around 1/2 to 1mm with gasket in place.

Only downside to the new shaft bushes is when I temporarily put the timing cover on, the kick start shaft binds slightly on one side of the hole. Still waiting on other bearings and seals so I'll look more into this when the engine goes back together - I'm suspecting the end of the kick start shaft may have a slight bend so need to check it out in more detail.

[oldaz]

Well, hopefully we learn as we go, it would have been wonderful to have an assembly type manual to refer to, instead of only having a parts sketch/diagram. Having put the kick start mechanism together and apart and the engine case on and off so many times, I've finally worked out what it's all about.

I made the new inner bush from high quality brass with an oil gallery as opposed to the oillite original type. The spigot end of the shaft only goes part way into this bush and repeated kicking will potentially/eventually cause it to fail.

The whole mechanism relies on the ratchet to disengage when the lever is in the "park" or "home" position and that's controlled by the timing of the outer section of the ratchet (4365.011) and the small guide (0265.10401). The full depth of cam on the ratchet must be behind the guide when the kick start lever is in the park or home position, and start to travel down the cam ramp immediately as the lever is pushed down. Failure to get this right won't allow the ratchet to catch on the gear section (2265.00103) early enough to give a full length kick and could allow a partial contact in the ratchet - that and/or poor spring pressure maybe why the kick start fails on some of these.

Once I've got the timing and assembly 100% including the .5mm thickness of the centre gasket, I'll measure the end spacers and post here - it might save someone else some headaches.

New bearings, seals and gaskets arrived from InMotion, so better get the case repairs finished and now really looking forwards to reassembly.

 

[oldaz]

Case repairs completed, new bearings and seals fitted, kick start clearance and timing set and the two engine cases now back together - progress!!!

If anyone is interested, the assembly order for the kick start mechanism inside the engine cases is as follows - kick lever side spacer is 1mm, then the circlip, another 1mm to 1.5mm spacer goes between the circlip and ratchet spring (this spacer not shown in parts diagram), ratchet spring, small ratchet part, large ratchet part, 4mm spacer against bush.

If anyone wants to know how to set the kick start timing to get the best out of it, please let me know. It's a little involved to explain, but I'm happy to try if needed.