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please help me...
Posted: Tue Sep 29, 2009 8:14 pm
by mattydrvf
Rite where to start. The last two times i rode my nc35 the oil light has come on at tick over but goes off when i rev it. Checked oil level and was fine. contacted my local mechanic and he said maybe my oil pressure switch had gone up the spout. Now, was riding it home yesterday and all of a sudden there was a horrible noise and a loss of all power. I can only describe the noise as sounding like a pound coin going round in a washing machine. The noise is not constant and kicks in randomly. Have taken the cluch cover off and drained the oil and there seems to be what looks like tiny shardes of a copper coloured metal in the oil and on the bottom of the clutch housing. Don't know if this is relavant but coolant bottle was empty but radiators are full and bike was nowhere near overheating.. Read up a bit and am thinking either along the lines of a bearing or bush something on the camshaft ( or even the camshaft) or a buggered water pump.. (Would a water pump make such a noise). Any advice would be very welcome.. Cheers.
Re: please help me...
Posted: Tue Sep 29, 2009 9:34 pm
by CMSMJ1
Thinking more terminal than that mate. Pieces of brass (rather than copper) would say that the main bearings are shagged
You did have low pressure and the bearings failed and it is dead....
I am sorry to be the first to tell you...but you need to get the oil dropped out of it and see what is in the sump.
If there are pieces of metail then you can be sure you have serious problems.
Re: please help me...
Posted: Tue Sep 29, 2009 9:38 pm
by mattydrvf
ok i have taken the oil out and there are just tiny particles of metal in the oil not alot though. Havn't taken the sump off yet but am i looking for big pieces of metal or tiny ones.
Re: please help me...
Posted: Tue Sep 29, 2009 9:46 pm
by CMSMJ1
could be both.. But metal particles in the oil is about as bad as you can get without pieces sticking out the sides of the cases.
If you plan on fixing it I would remove the engine. Either way, it is reuilt or you buy a new engine...it needs to come out.
Get the sump off and see what is in there!
Re: please help me...
Posted: Tue Sep 29, 2009 10:29 pm
by fastdruid
You can fairly easily check for big end failure without dropping the engine.
Take the plugs out, use a spanner to turn the engine over and for each cylinder take the piston just past top dead centre (basically when the piston starts to go down again). Use something to push down on the piston while making sure the engine doesn't rotate, if you can push the piston down[1] the big end on that cylinder is fscked.
If you're not sure rather than rotate it 360 degrees you can just turn it until the piston starts to fall again and repeat.
I can't remember on the NC30/35 if you can reach the big ends through the sump, some bikes you can at least see them, some you can take them off, some you can't even see them!
Druid
[1] About 4mm of movement if it's *really* screwed but you should be able to tell the difference between some movement (broken) and none (fine).
Re: please help me...
Posted: Tue Sep 29, 2009 10:47 pm
by Neosophist
Interesting one that.
I'll go with the big-end theory (engine write-off

) without seeing it.
Maybe somethign was partially blocking your oil pump and it got starved of oil?
Big end bearings usually make a rumbling noise at low rpm.
You'll know when you take the engine apart!
But as been said, mechanical noise and bits of metal in the oil is about as bad as it gets

Re: please help me...
Posted: Tue Sep 29, 2009 11:43 pm
by hunter
Yep copper colour in the oil,Big end or Main Bearing.
Re: please help me...
Posted: Wed Sep 30, 2009 3:21 pm
by royster81
does this mean i can buy your cams mate ?
Re: please help me...
Posted: Wed Sep 30, 2009 4:21 pm
by CMSMJ1
I'll buy the cylinder heads....lol
Re: please help me...
Posted: Wed Sep 30, 2009 4:25 pm
by rich1988
Can I have your TV?