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oil blowback

1074 Views 7 Replies 5 Participants Last post by  ramprat06
Ihave a 1980 cx500 that's was sitting for quite a while.finally got it to start,burned oil for about 10 after it,s warmed up it starts to blow oil from the crankcase vent.could i be looking at stuck rings or is it something else.
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How do you know it's blowing oil from the vent?The oil breather pipe should run into the Air-box.

You can download a manual from here.
it started to leak from drain under airbox.disconnected vent to airboxand let it run draining it into a will leafill a 4oz jar in no time.
With the bike being stood there may be a good amount of water vapour/condensation around inside the engine and in the engine oil.I take it you haven't changed the engine oil yet?

Check the oil level in the bike,

and for now top it up if it needs it.Use any old engine oil for this e.g 20w50 cheap mineral oil if you have it around but standard 10w40/15w40 will do.

Run the engine up to the thermostat opening running temp.You can tell when this is by touching the Chrome coolant pipe on the side of the engine.It will get warm when the coolant starts to flow after the thermostat has opened.

See how it does.I suspect all it needs is this and then to change the oil and filter and then give it a good ride.

If you want,and I suggest you do this, you can clean out the Air-box by taking the Filter out and pouring a couple of kettles of boiled water in there with the plugs out of those drain pipes.Then dry up with some Toilet tissue inside the box.

Once you've done the above it may still put a little out of the pipes for a while until it clears.

Does the engine itself sound ok e.g not too noisy?
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If it is blow-by, then you need rings

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Do a compression test to see if it's the compression rings or just the oil control rings. There are some chemicals that you can add to the crankcase to help unstick the oil control rings.
I pulled the plugs,poured in some marvel,let it sit a few days,problem solved.Thanks for your input.
Nice to hear a quick resolve, although you probably should still do as Shep suggested regarding the airbox. Then at least you have a reference point.
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