Hey guys like to add my 2 cents and maybe get some help. Mine is the 18hp ohc,wont turn thru the comp stroke with a known good battery,starter good and all connections good,set the valves at .004 1/4" past tdc. I understand you should see a slight decompression coming off the cam just b4 tdc. I have no movement in the pushrods whatsoever. Suspecting bad cam. How do I get to that? Anyone know where I can access a disassembly/shop manual? Im kind of over my head here. Doing favor for my neighbor. He says go for it but I would like some kind of instrucions. Thnx

Most likely thing is the valves need adjusting, very common on OHV B&S engines. Compression Release works off Intake Valve, excessive clearance prevents Compression Release from working properly. For detailed instructions on adjusting, wconner5 at verizon dot net put in proper format. Walt Conner

Update....the engine is running!!! My son and I had faced a setback earlier in the week when one of the head bolts sheared after the second round of torquing to 36 ft-lbs. That was a bummer, but a couple days later we got the bolt out with an easyout. We put all the parts of the rider back together (with a new needle/beam torque wrench) and fired it up with some carb cleaner, and it started up fairly quickly!!! As expected, we did have the smoking of burning off of oil, but after 20 minutes or so, that seem to diminish to nothing. Seem to have a little bit of burning oil smell still, but I am hoping that is just some residual oil burning off the frame or muffler shields - those parts around the muffler seem to get very hot. Only remaining issue was a backfire after turning it off. It happened half the time after shutting it down, even when I would let it idle for 15 seconds before turning it off. But I can probably live with the backfiring. I would welcome any input on this problem, but I can do some research on the internet about this seemingly separate issue. Thanks so much for walking my son and I through our first fix of this magnitude....usually we only fix fuel problems. It was a really satisfying experience, and I am really grateful for your advice along the way....I was truly amazed. Again, thanks so much.

Well, the answer to the part about spark ignition timing is that this engine does indeed make twice the number of sparks than the number of compression strokes. This is not the only engine that does. Just about all engines that have a magneto ignition timed to the crankshaft do this. It is called "wasted spark ignition" because the magneto fires every time the flywheel magnet passes the magneto (coil). The useful spark occurs on the compression stroke, and the wasted spark occurs on the exhaust stroke. What are you basing the statement "It's getting fuel" on? You might be getting fuel as far as the carburetor inlet but that does not mean fuel is actually being processed through the carburetor and fed to the engine. Shoot a couple of shots of spray carburetor into the throat of the carb and then try to start the engine. If the engine runs for a few seconds on the carb cleaner (call it "alternative fuel"), then the carb is not feeding fuel to the engine. Look at the image below to help you find the model and type numbers of your engine. The surface you will find the numbers on is the sheet metal cooling shroud of the engine. Try the carb spray, and then post back with the model & type numbers and we will proceed from there.