Hello all!
I am new to the forum but I have already been able to learn quite a bit by reading through posts.
I currently have an old (1998) Craftsman Riding Mower with the 18.5hp Intek V-twin motor in it. It is used in rural Santa Clara County climate of the California Bay Area. It is used during late spring through mid fall. Temperatures can range from 80 to 100+F during these times in this area and it is usually dry, sometimes very dry.
The land is extremely rough, hilly, and rocky and beats the absolute heck out of the mower. It does get dusty, but can also get a little bit wet during the first cuttings of spring when the big weeds hold water. The weeds can easily by 3+ feet high.
So far the mower has been great and I just go slow and steady and I know the land really well so I know how to avoid most of the big problems. I am dealing with ~6 acres.
Recently, the mower was blowing smoke (Like smoke screen amount of smoke). I've been around motors and power equipment, motorcycles and cars all my life so I could tell it was oil. I figured the valves weren't adjusted and when I looked at them they were very tight (almost like 0 lash). I did an adjustment and the smoke stopped immediately, but I want to be sure I adjusted them right. Here are my questions:
1. Craftsman says both intake and exhaust get adjusted to .004. I have read this motor uses .003 for intake and .005 for exhaust but I have no way to confirm that. Anyone know? I don't have a manual for the motor, just the mower itself.
2. I *believe* the bottom valve is intake and the top one is exhaust on this motor. Is that correct? I know the intake is supposed to have aluminum push rods, but I can't tell for sure.
3. Finding TDC is easy, and going 1/4 past that is fine, but without marking how can I be absolutely sure I'm on the compression stroke? The way I did it was rotate until the intake valve closed and then opened all the way up and before the exhaust valve started to move (They were both open as wide as possible) that was where I did the adjustment (which was about 1/4 past TDC of whatever stroke I was on). Am I close?
4. Craftsman says adjust the plugs (Champion RC12YC) to .040. Some other places B&S says .030. Is one "Right"?
5. Finally, I could go a step hotter in the plugs to the RC14YC but I don't have any real starting issues when cold. Any thoughts on a reason to go a step hotter?
Thank you all so much, I'm hoping I can get this mower working correctly again!