burning oil

So my left side exhaust is burning white/grey smoke after it's warmed up. I got a start on pulling the head again and I can see oil on the left combustion chamber and top of the piston. Any way to tell if it is head gasket, piston rings. or valve guides. I really hope it is not valve guides the bike only has 10k original miles on it.

Air pressure to the jugs at TDC then listen for escape noise, out the breather means rings out the rocker box implies guides, out the carb implies intake valve seat and similar for extaust sounds out the exht. seats. Otherwise just fix what ya find then put back together and go from there. Rings smoke tends to clear up when hot while smoke gets worse hot with guides. On throttle smoke implies rings while off throttle smoke implies intake guides. Of course being a Commando implies all at once.

Wadep77 said:

So my left side exhaust is burning white/grey smoke after it's warmed up. I got a start on pulling the head again and I can see oil on the left combustion chamber and top of the piston. Any way to tell if it is head gasket, piston rings. or valve guides. I really hope it is not valve guides the bike only has 10k original miles on it.

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Always easier to gather information when it is assembled and running; did you get a compression test before dismantling? Can you still do a test with the partial dismantle. A significant low compression on the oily cylinder might support a fragged ring; squirt some oil in the offending cylinder and see if the compression goes up any - if yes then probably rings, if no then maybe a burnt or leaking valve. Oil on the piston pretty much rules out exhaust guides. Are there intake guide seals on your model, did one slip up off the guide?

Did the white grey smoke come on gradually or all at once or after some hard abuse. More details the better.

I already have the head off and did not do a compression test. I don't know how. I had the head off last year to get an exhaust port fixed. When I put it back together it ran good. I re torqued the head often too(every 50 than 100 miles. Toward the end of last year I noticed the smoke and fouling left spark plug. The plug gets black and wet. I probably should have paid more attention to detail before tearing down. The bike would still start one kick, I would go for a ride and when I would get back it would sputter a little smoke at idle and if I gave it gas it would pour a puff of black followed by white/grey smoke. I need to re set float height on carbs probably causing the black smoke. While it is apart I may redo everything (head, and rings) over time. I emailed Colorado Norton works about a full head rebuild price but I'm guessing it's out of my price range for now. If any of you know someone that rebuilds heads at a good price let me know. I have an other bike to ride now so I can take my time with the Norton. Thanks for replies and any help.

Wade

Wadep77 said:

The bike would still start one kick, I would go for a ride and when I would get back it would sputter a little smoke at idle and if I gave it gas it would pour a puff of black followed by white/grey smoke. I need to re set float height on carbs probably causing the black smoke.

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Based on the easy start - black smoke - white smoke sequence, I would venture a guess that it's an overly rich carby causing oil to be washed off the left cylinder wall contributing to heavy ring wear. Steve/Hobot's on it about running a compression test first; even though it's past that point. If nothing else, run a proper leak-down test once you get the engine assembled and properly run in. You can then use these values as a baseline for future troubleshooting. Would anyone out there like to know how to buld a leak-down tester on the cheap? Let me know... I built one out of spare parts during my aircraft mechanic days, and it's perfectly acceptable by the FAA to do so if the restrictor is built to some specific dimensions.

Nater_Potater said:

Wadep77 said:

If nothing else, run a proper leak-down test once you get the engine assembled and properly run in. You can then use these values as a baseline for future troubleshooting. Would anyone out there like to know how to buld a leak-down tester on the cheap? Let me know... I built one out of spare parts during my aircraft mechanic days, and it's perfectly acceptable by the FAA to do so if the restrictor is built to some specific dimensions.

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For engines up to 1000 cubic inch,the standard restrictor has a 0.040" hole 1/4" long,with an entry angle 60 degrees included.
Regulate the pressure leading to the restrictor (usually 100 psi).
Read the pressure between the restrictor and cylinder with another pressure gauge.

I used a regulator (with gauge included),restrictor,2nd gauge,flexible hose to suit a grease gun (brake hose or nylon hose would do),adaptor with spark plug thread,and a few other fittings to join it together.

Wadep77 said:

I emailed Colorado Norton works about a full head rebuild price but I'm guessing it's out of my price range for now. If any of you know someone that rebuilds heads at a good price let me know.
Wade

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A fully rebuild head is going to cost you upwards of a grand no matter who does it unless you want crap work. You can easily do almost everything except install new guides yourself with ordinary tools. That may be worth looking into.