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- This topic has 65 replies, 9 voices, and was last updated 6 years, 3 months ago by KennyS.
10th November 2016 at 7:14 pm #6082
At my age I should know better than buy off ebay unseen.
Finally got a little tinker with the new distraction. Put some oil in it and tuned it over by foot a few times with the plugs out. Put a good battery on but wouldn’t turn over.
Oh well, that’s why I wanted a kick start. It had a half hearted attempt at firing. Both plugs had a spark.
Checked the compression, right hand pot had 75psi after 3 kicks, left hand pot had zero, doh!
Only time I have ever seen zero was a car engine I melted the piston on.
Need to check tomorrow if the piston is going up and down and if the valves are closed.
In the meantime it’s off for a stiff drink and start sorting some spanners out.10th November 2016 at 7:38 pm #13840philpassinghamParticipant
Steady as you go there,just keep doing a little at a time11th November 2016 at 10:27 am #13869
Was the bike stood for any length of time ?
Could be the rings have seized to the piston.
Maybe a slug of paraffin, etc. overnight might do the trick.
Are valves closing correctly?
Either way – good luck11th November 2016 at 4:52 pm #13885
Worse than that I suspect. OK, here’s one for the clever people. Did a quick check today and it seems to be an errant piston. It’s not fulfilling it’s primary obligation of going up and down.
Well, not strictly true, it’s gone down at some time, but refuses to come back up.
The right hand piston moves, so it’s not a broken cam chain. If it was stuck at the top I would suspect it’s detached from the rod but surely the rod should be trying to push it up.
Is it possible for the sprocket to come off the camshaft, but everything sounds ok when turning it over.
Maybe it’s been converted to a 375cc single.11th November 2016 at 7:35 pm #13841philpassinghamParticipant
Strange one that,paraffin down bore and leave overnight12th November 2016 at 10:05 am #13880MikeonabikeParticipant
Broken Rod, Crank or Big end cap come undone, I think you can remove the sump and have a look inside but I would fear the worst 🙁
Good old E-Bay, I just bought a LED floodlight, instructions say connect Blue wire to LIVE!!!!!12th November 2016 at 11:35 am #13870
That was the accepted method to free rings back in the 50’s and 60’s before commercial anti-seize products were available – worked too ! Redex and Plus Gas also worked, but yer Mum usually had a can of Esso Blue or pink [ name fade]in the shed that cost you nothing!
If you think adding paraffin to soak over night is weird, then you probably have not heard of the method used for freeing a seized piston to bore ?
Add the paraffin over night, and then set light to it the next day ! That also worked in 50% of cases.13th November 2016 at 10:24 pm #13886
Engine nearly ready to lift out, it’s a heavy lump, or am I just getting weak. It doesn’t have a centre stand so I’ll need to support the bike some how, while I wrestle the engine out.Must remember not to wear trainers.14th November 2016 at 12:11 pm #13854MichaelParticipant
the complete engine is 78 kg !
Remove the valve cover first, that eases the job.
Having the bike on side stand is not too bad, as you have to remove the engine sideways to the right.
Fix the chassis against rolling away. (Strap on hand brake, etc.)
Cover the right hand, lower frame tube prior to engine removal with cloth to avoid undesired damage. (see pic)
Engine needs to go up (vertical in upright position, adopt to side stand position) and must get out of the lower rear holder. Then it is needed to lean/tilt it to the right hand side and moved out by letting be the cylinder head the pathfinder.
If it’s got jammed, recess it to whatever position it will take, have a rest, calm down and then try again.
I would highly recommend to do the job with two or even three persons !
Two to handle the engine, the third to support with whatever is needed 😉
If you need some engine parts and can’t find it in the UK, I may send some from Germany to you.
PS: Pic shows the removed engine of one of the rare Y2 LTDs.16th November 2016 at 1:35 pm #13887
Thanks for the tips. I have to go back to work now so play has stopped for 2 weeks. The engine coming out wasn’t really on the original plan, I was hoping to ride this one while I sorted the other one, but hey ho, that’s life and it will give me an insight as to how the other engines go back together. Are gaskets, bearings and stuff easy to get hold of.16th November 2016 at 10:54 pm #13843KaptainkwakKeymaster
The camshafts have nothing to do with the pistons going up and down. That is soley controlled by the Crankshaft.
Is there a piston in the bore? One piston moving and the other piston not indicates either a broken Crankshaft (unheard of) or broken/NO conrod.
Keep us posted as you find things out. I do have many engine spares22nd November 2016 at 8:35 pm #13888
I’m back at work for 2 weeks so can’t play with till then. My gauge rod ( piece of stick ) went into the cylinder as far as it did on the good pot with the piston at the bottom. So it looks like it has a piston in there, just not connected to the crank.
Yeah, I did realise my post about the camshaft was nonsense after I had posted it, just random rubbish that was passing through my head at the time, probably not helped by a couple of stiff single malts.23rd November 2016 at 8:53 am #13871
If the piston was NOT connected to the crank [ for whatever reason ]it would stay at the top of the bore on the downstroke ???24th November 2016 at 10:23 pm #13889
Yes, I would have thought if the con rod had snapped it would leave the piston at the top. There are no nasty noises either when you kick it over, it sounds fine. I did think I was getting better at kicking it over, my last one was a lot harder, but then it did have two pistons.24th November 2016 at 10:34 pm #13872
Prior to removing the head ( looks inevitable ) get a piece of thin dowel / similar and have a poke around the piston crown when it’s near the top of it’s stroke. That way you should be able to determine if there’s a hole in the crown. Petrol poured in at around tdc will work. If it disappears rapidly – there’s a hole !
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