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dont let this happen

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davepainter:
Well found out what the fault with the float bowls was, a snapped camshaft-OUCH??
carefull buying on e-bay to be honest the guy i bought this off probably thought he had cleaned thoroughly just goes to show
basically something blocked the oil feed to cylinder 3+4 camshaft.
i,ve yet to inspect the head and VALVES scary.
within 2 hours i found a mint cam carriers and followers for my 76 k6 inc postage from good old USA for

steff750:
 ::) 4 times in 30 years, yes been there done that and had the t-shirt.I'm surprised you did not hear the camshaft seizing up, they make one hell of a squeal before they give up the ghost  (a sound i will never forget or want to hear again) mine snapped as i tried to get home i was only about two miles away so limped home on two cylinders,the problem in my case was stripped threads on the cam cap bolts and a bit of crap welded its self too the camshaft, ,everything under the rocker box had worked loose from previous owners rebuild it had run for six years so cant be to harsh on him ,the head has since been heli-coiled so better than before , you will learn from this ,so don't feel to peeved,i think it has happened to quite a few of us .i would say most likely bent valves aswell in my case anyway.just make sure them oiljets are clear and be ultra clean on the rebuild i always spin my engines over on the bench with the battery connected to the starter motor and check for plenty of oil on the camshaft, before installing the engine,this used to be a bit of p*ss years ago, with plenty of old chops about for spares and gasket sets only costing twenty quid ,just swap heads or even engines and off you go not any more lol   ;)

UK Pete:
Yes it does seem to be a common problem, kind of makes you feel paranoid for a while after a rebuild and riding for the first 500 miles or so
The problem after something like this happening is all the ground up bits of metal that have managed to circulate around the rest of the engine, i would only be happy to run it after a full strip and clean out of entire engine after that
Pete

hairygit:
Steff, the odd thing was that the side of the cam with no oil supply was for cylinders 3+4, which were the only 2 running! The cam snapped leaving the part above cylinders 1+2 not turning, but the oil supply to them looked okay! ???

davepainter:
Well spotted,its going to be interesting ? to see which valves if any have been affected
my geuss would be that up untill the exact moment the cam snapped 3+4 were firing to allow bike to run?
however ground zero day at 160 miles on clock 12-9-2011  cylinders 1+2 on inspection as suggested by yourself were found to have NO play in tappet arms,---
 The last time i rode the bike with all 4 cylinders running was 29-8-2011.at 160 miles,as you say odd that the undamaged looking side 1+2 was the side i,ve had constant stop start, wont run then ok then not.
when i had the bike delivered with 8 miles on the clock,from new engine build and start, it did,nt run on 1+2 the FIRST time i started her i had to ring the guy i bought the bike from and asked him what main jets he was running, i ASSUMED it needed bigger jets i ordered and tried 120s then 110s before putting the 105s back in which were the ones in the bike when it was delivered!
 So mr watson for some reason all the time (160) miles that the cam damaged side 3+4 was disintergrating and turning into molten metal,
the bike covered at least 140 good miles running on all 4.
 the 5 or 6 times i went out and rode 20-30 miles at a time good --then next time i went to use her she WOUld,NT fire on 1+2
Like you say its strange all the damage was being done to 3+4 .
prediction time i reckon when head comes off i,ve bent valves on 1+2--caused at the exact moment the cam snapped!!!!






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