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Small crack cylinder head cover
Posted: Sun Nov 02, 2014 4:47 am
by Icemaestro
Hi all,
Slowly doing up an nc30 that has been siting for 12 years. 2 carb cleans later and new rubber hoses, float gaskets and carb adapters later and she is now firing on all cylinders (roughy, assume carbs still not quite right)...now oil level is bang in the middle, has even stored with oil in it (and will do an oil and filter change now that it's running) but...
have noticed a small crack in the cylinder head cover..see below pictures. It weeps oil slowly...a drip every say 15 seconds or so. Apart from replacing the cover (I assume this could be done with valve clearances?) is there anything I can do? Put a bit of jbweld over the top?


Re: Small crack cylinder head cover
Posted: Sun Nov 02, 2014 12:34 pm
by abrmoto
I would just replace the cover only about £20 of here or eBay.
Re: Small crack cylinder head cover
Posted: Sun Nov 02, 2014 5:08 pm
by lukemillar
I have a spare you can have. PM me your address and i'll get it in the post
Thanks
Luke
Re: Small crack cylinder head cover
Posted: Sun Nov 02, 2014 6:51 pm
by Icemaestro
I am assuming there is a asker that needs replacing at the same time, and as i said I plan to replace, probably when valve clearances are checked, but need to get the bike running first! Would jbweld work for the short term do you think?
Luke has said he'll send one up :-) thanks luke! It's generally a bit harder/more expensive to get nc30 parts here in nz, a lot of uk people on eBay don't want to send here
Re: Small crack cylinder head cover
Posted: Sun Nov 02, 2014 10:54 pm
by britaxcooper
They're alloy aren't they? It'll weld up?
Re: Small crack cylinder head cover
Posted: Tue Nov 04, 2014 3:45 pm
by Neosophist
jb weld will work fine, rough up the area and clean it all of oil.
you can take teh rocker box cover off no trobule, the rubber gaskets are designed to be resubale but can crack and break with age, be areful when you take the cover off.
if you do separet the rubber gasket and the cover check the service manual they have to be siliconed in place, if they dont separate on remove then just leave it in..
you can tig it too if youve got a tig wlder or use some lumi-weld type rods to fill the hole if you have a good torch / o2 kit aroudn (obv take the rubber gasket off when doing this repair work)
Re: Small crack cylinder head cover
Posted: Tue Nov 04, 2014 9:12 pm
by hunter
Qestion is what has done the damage.
Re: Small crack cylinder head cover
Posted: Tue Nov 04, 2014 9:49 pm
by Icemaestro
Thanks neo, gold as always. Don't have a welder, but you've made me feel better about pulling it apart....I think if I has the tools and valves I'd attempt the clearances too but I don't.
I agree hunter, it seems odd to me, I don't think a rock could have gotten there, hence why I posted wondering if anyone has had the same.it is on a little bobbly bit cast into it, maybe it's a slight weak point? The bike runs on 4 cyl now and no bad noises that I can tell. Once I have it running on the road I'll prob take it to the genius nc30 mechanic we have in town...has owned about 35 of these... As I suspect my idle jets are still blocked (the side holes clear but can't see through central hole), and I wasn't very accurate with my home made float height checker, carbs need to be synced, valve clearances done, wheel bearings replaced, possibly steering head bearings, tyres, chain and sprockets....
Re: Small crack cylinder head cover
Posted: Wed Nov 05, 2014 12:43 am
by VFRkieran
Id bet that's your radiator contacting the rocker cover and the crack has appeared over time going over bumps etc.
Re: Small crack cylinder head cover
Posted: Wed Nov 05, 2014 2:04 am
by Icemaestro
Ahh :-) the fork seals do need doing after sitting for 12 years...(also, very slight bits of rust in the travel area...thoughts? Hoping not to have to replace the stanchions, but if I did, do they need to be from the latter model forks, or can I take them from an 89 bike?