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[jawa-enfield]

I tried putting it in the oven at 120 degrees and shock oil, no effect,, tapping/pulling with a leg from a puller also no effect.
Only thing is cutting it in half? I cannot imagine a widening bolt (don't know name in Englisch) has enough grip, plus the expanding makes it more snug?

[papasmurf]

I tried putting it in the oven at 120 degrees and shock oil, no effect,, tapping/pulling with a leg from a puller also no effect.
Only thing is cutting it in half? I cannot imagine a widening bolt (don't know name in Englisch) has enough grip, plus the expanding makes it more snug?

An example:-
https://www.youtube.com/watch?v=t7VQnNfqJtA

[jawa-enfield]

Also, the bearing bush and first gear sprocket are fused to the layshaft and cannot come off, so have to buy these also new.. much like the kickstart assy su°ince bush is unremovable and now damaged by hammering.
these bikes are not easy to work on, but quite expensive to overhaul in this way.

[Wheaters]

In that case, don’t waste your time trying and I’ll not waste mine offering advice.

[jawa-enfield]

Even under a press it won't go...

I managed to remove the iron layshaft bush form the kickstart unit.. first i made 2 gutters with a dremel opposite to each other, trying to almost get it 'trough'.
Then with a small hammer and chisel 'broke'the remaining layer in the gutters and could fiddle the remains out. the motherbusch is quite unharmed, but did some minor sandpapering anyway...

plan is, whe installing the bronze layshaft bushes, to freeze them and put the recieving parts at 120 Celcius in the oven.

My apologies to all readers for previous post.. had a bad day, no patience, no India-stamina of mind...

[jawa-enfield]

Do you use gasket maker/paste at the crankcasing besides the paper gasket?
It was bonded together with some kind of gasket maker.. was difficult to separate the halves.
I don't know if this is from factory or not?

[stinkwheel]

I don't think they have one from the factory judging by the engines i have stripped.

I generally use a non-setting sealant on them for reassembly. I use permabond A136 on most mating surfaces but it's expensive (smells good).

Threebond would be another good option in this application.

[jawa-enfield]

Okay, that would imply that the engine has been opened before.. but why? The original bearings were still in place. But again, it seems this was an inland version (17T sprocket, iron layshaft bushes, single leading front brake).

There's silicone based stuff and brown stuff in a jar with a small brush..
'normally'i would trust on paper only..but..

New challenge; applying the gasket maker quick while cases are still hot (burnt fingers) and not letting them cool too long before inserting the cold crankshaft..

[jawa-enfield]

I got all the parts i need for rebuilding the engine.
Must admit i am somewhat worried about assembling the engine.. what is the (cold) crankshaft won't fall into the bearings, (of the heated casings)What if i have to press or hammer the parts in each other distorting the crankshaft?
Argh!

[stinkwheel]

Last time I did this, I fitted the hot bearing inner races to the chilled crank seperately. I had a piece of appropriately sized, pre-cut steel tube ready to use to wind them fully into place using the nuts on the end of the respective shafts.

I fitted the drive side outer bearing and the remaining parts of the two inner bearings to the crankcases by heating the cases and cooling the bearings in the usual way.

Then I fitted the crank to the cases and fitted the gasket with everything at room temperature.