I have a Gravely Professional 8 hp with an odd Kohler motor, apparently. The engine tag lists it as a K181, but Ive had better luck with M8 parts manual.
Starting with the cylinder head, got the machine with helical coil for spark plug and it eventually popped out 10 years later. Recently replaced with M8 "fin-top" cylinder head (#2: 41 015 09) which is identical to K181 (#12: 41 015 01 / 41 015 06 / 41 015 07). The cylinder head gaskets are the same part #s between K181 and M8 (#13 or #8, 41 041 10) for the "fin-top" heads. There is another K181 PM lists this gasket as 41 041 05.
Now on the spark plug, the K181 calls for a Champion RJ8C (0.375" reach), while the M8 calls for RCJ8 (0.750" reach). Going back to cylinder head parts, the K181 has 2 (#16, 41 015 05 / 230451 "bottom block", and #12, 41 015 01 / 41 015 06 "fin-top") cylinder heads. The M8 does not have the "bottom block" cylinder head, but it has a longer spark plug? Wouldnt it then sit even closer to the piston?
"Bottom block" brass head gasket part #15: 230452.
Gas tank assembly on my K181 is also, for some reason the one for newer M8's with a plug-style straight fitting at the bottom (41 294 01), discontinued unfortunately.
If someone might know which of the Champion spark plugs I need? Why is it longer on the M8, without having the raising "bottom-block" 2nd cyl. head?
