Don't try to take off the camshaft cover - it's put on with an adhesive sealer and they don't leak. Have you checked the oil to see it it is over-filled? Was the mower stored sitting flat on it's wheels? The only oil leak I have seen on the Honda overhead cam engine is around the governor shaft at the rear of the block. If oil level is good, just run the mower and see what happens. Try to determine if it's an active leak and where it comes from.
Was the mower tipped up on one side at any time? If so, this is most likely the source of the oil. You'll have to replace the air filter if oil-soaked and remove the spark plug to cycle the engine and expel oil from the cylinder if the engine feels 'locked up'.
You can tip a mower up, but the carburetor (air filter) has to be on the high side.

Is it ok to resurrect this old thread? Hope so :)

I think I have the same problem as kirkiesgirl. I have a Honda HRX217TDA (belt-driven self-propelled) made about 2007 only used about once a week on a half-acre lawn. Oil changed annually etc., lots of love.

Last week a puddle of oil appeared beneath the mower, several ounces at least. The cylinder bottom - where the fins are - is wet with oil. The wettest spot seems to be the joint with the cylinder head.

The oil filler tube is dry and dusty. Sure I tip the mower on its side to change the oil, but have not done so recently.

Engine crankcase still has enough oil - level is at the middle of the dipstick when placed in (not screwed all the way in). The machine runs fine as far as I can tell.

I hope saxman1 is still following this forum :) thanks in advance for any hints

On your oil level, if it is actually in the middle of the dipstick, it is overfull. If you meant in the middle of the crosshatched area, the level is fine. If you snap off the air filter and it is oil soaked, it will have to be replaced. there isn't actually a cylinder head on your engine, but it is possible to leak from the valve cover. They are not noted for it and as Sax wisely put it- you want to buy a new cover and a tube of sealant before you would reseal. It could be done with an old cover, but they are on the flimsy side.

Chris; on the Honda, the dipstick is not screwed in at all to check the oil - just put it in the fill tube until it stops. Tipping the mower over to drain the oil is normal and will not cause a problem - its when you raise the side with the oil fill that oil may get into the carb. I would be inclined to say that somebody tipped the mower the wrong way at some point, maybe to move it or who knows what, but that's what causes these sudden oil puddles. Check the air filter for oil - should be none - replace if it is. Use a degreaser on the oily areas and hose it off. Pull the starter cord to see if it pulls through normally. If so, go ahead and start it. It will probably smoke pretty bad until it burns the oil out of the muffler. If it won't pull through, you'll have to pull the spark plug and blow some oil out first.
You'll want to make sure the oil level is correct before starting it. Unless it was over-filled, you definitely lost enough oil to make a difference.

Thanks for the reminder, I should have checked before posting yesterday. I wish the explanation were as simple as the mower having been tipped onto the wrong side! Today I double checked the air filter, it's dry and dusty with no trace of oil.

The mower starts easily and runs with no trace of smoke.

The oil level is at the middle of the cross-hatched area on the plastic dipstick when the stick is rested in the fill tube (not screwed in).

This is looking to me like a serious problem. :(

Okay, the oil level should be at the top of the cross-hatched area, so its a little low, which you would expect with some kind of leak. So, did you clean it up to determine if its an active leak?

My local mower shop speculated that the head gasket may be leaking. I dropped it off for professional repair today.

Let us know what happens. On the Honda OHC engine, there will be no oil to speak of in the upper cylinder. If you blew a head gasket, it might not run but you wouldn't expect to see much oil there. Maybe he meant the cam cover? They are not known to leak, but anything's possible.

Okay, thanks for the info. I'll keep that in mind.

ChrisInMtown, you are AWESOME!!!!! I'm sure I have the EXACT same problem. Thank you for the part # !

BTW, its actually the 'cam cover'. The 190cc GSV engine has a cast aluminum cover which is much better. I don't know for sure that it is a direct replacement for the stamped cover on the 160cc GCV but its worth looking into.

There is a seal that is available for the area where the governor shaft comes out. It is not installed on the "residential" models, only commercial, from the factory. Part number 91231-891-003 from Honda. It's about 2.50 from your local Honda dealer and easily installed.

I have a 'commercial' GSV190 and it leaks at the governor shaft too so there's no seal. But thanks for the tip. I should pick one of those up on the offhand chance that I'll take the governor linkage apart someday and put the seal on the shaft.

Leak on governor shaft will that cause oil to spit onto the back of the deck on both left and right sides?