I noticed a large plume of blue-black smoke when I let completely off the throttle and got back on it (bout 1/3 throttle, had to pass someone), and just happened to look in my rearveiw mirror. I know from some searching that it needs valve guides. I need to know **what else could it need as well?** Seals? What else should I do besides a tune up afterwards (to get rid of the plugs that I am sure are oil-covered)?

Also, How long can a problem like this go? At the earliest, I would be able to fix it in August.

Any help would be greatly appreciated.

Thanks,

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