I have a Honda GCV160 engine that smokes at start up. The oil was a bit over filled. Not terribly. I fixed that and it still smokes a bit at start up. It goes away after 5 to 10 seconds. Passed a leak down test with flying colors. A little bit of air leaking out the oil fill tube. The valves are tight. Pretty normal for a mower engine in my experience. I am thinking it is worn intake valve seal. There is no head gasket on these engines because of the way it is designed. Am I missing anything?
Keep the oil ON the full mark. Not under nor over at EVERY mow. Like the old timers did it back in the day.
Over filling any engine causes issues. Oil aeration, oil pump cavitation, loss of oil pressure and so on.
Over filling any engine causes issues. Oil aeration, oil pump cavitation, loss of oil pressure and so on.
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It may take running multiple times to get over being over filled with oil. The breather also likely got excess in it so it may take time to get it cleared out.
Excellent input Auto Doc. I will check the breather and clean that out as well.
If it was over filled, it was over filled. Drain out the excess. Don't try and run it to burn it out.
Remember all that extra oil burns away and makes carbon. Carbon quickly shellacs up the cylinder and valves.
That Honda engine is normally a good long term engine with just little bit of TLC, especially changing the oil and replacing the oil with the proper type.
If the engine is smoking at normal oil levels it's probably worn out due to neglect due to not changing the oil. Why because on some of the GCV Honda 160's do not have a oil drain plug which enhances the oil change being neglected. The oil either has to be drawn out the filler tube or the engine turned upside down and drained and afterwards of being upside down they are usually hydro locked due to oil in the cylinder and hard to re-start and smoke like a freight train for awhile.
If the engine is smoking at normal oil levels it's probably worn out due to neglect due to not changing the oil. Why because on some of the GCV Honda 160's do not have a oil drain plug which enhances the oil change being neglected. The oil either has to be drawn out the filler tube or the engine turned upside down and drained and afterwards of being upside down they are usually hydro locked due to oil in the cylinder and hard to re-start and smoke like a freight train for awhile.
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Here is a similar build to your engine:
PartsTree - Home of OEM Parts for Outdoor Power Equipment
Parts lookup and repair parts diagrams for outdoor equipment like Toro mowers, Cub Cadet tractors, Husqvarna chainsaws, Echo trimmers, Briggs engines, etc.
www.partstree.com
Valve seal #10 can be changed by pulling the valve cover but some small cord has to be put in the cylinder before removing the valve spring to prevent the valve from dropping too far down in the cylinder. Compressed air works well also with both the valves fully closed. The intake spring fairly easy to get off by hand.