Question Yes it does have oints. I ddn't touch anything in the motor exept the cam shaft and tappets. From what you have said I think it is mechanical. How do you insert tappets according to the valve clearence?-------------------------
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Ya, the cam shaft did come out. I matched up the timming marks. The thing that kills me is the flame coming out of the exaust. Whats that all about?-------------------------
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Hi, I recently disassembled the base of my mower exposing the crankcase. The tappets and the oil slinger cam off in the process of taking off the base. I have re-inserted the tappets and the slinger. Now my lawnmower is hard to start and when its running it gets so hot that flames come out of the exaust.(maybe too much oil) What is causing this, is it the way I installed everything back together? My hunch is the oil slinger.
Answer -
Did you have the cam shaft out of the engine? I'm assuming so since the tappets fell out.
Did you line up the crankshaft and camshaft timing marks?
Eric
Answer -
There are a couple of factors that could cause the flame out the exhaust: 1) Mechanical timing or 2) Ignition timing
Mechanical timing is controlled by the cam/crank timing and the valve clearance. The valve tapped are supposed to be the same lenght but the intake valve clearance is .005-.007 and the exhaust is .009-.011. Use a feeler gause to check the clearance. I've been told that you can place the timing marks on the crank and cam 180 degrees out of place but I have never found this. When we used to rebuild engine I always rotated the crank through all 4 strokes before putting the bottom case on to make sure the mechanical timing was correct. You can also check the mechanical timing by observing the valve overlap. All 4 cycle engines exhibit valve overlap when they are properly timed. Both valve will be slightly open at one of the TDC strokes. Normally you can't see the overlap but you can usually rotate both vavles by hand or with a valve lapper.
The ignition timing is controlled by the flywheel key and points if you have have them. Does your engine have points?
Let me know.
Eric
AnswerThe tappets are supposed to be the same lenght but over time they may wear. The only way to check the valve to tappet clearance it to remove the valve breather, set the pistion to TDC and measure the gap.
Newer manuals tell you to rotate the piston 1/4 inch past TDC to check/adjsut the valve clearance. This method began in the mid 90s so either TDC or just past TDC should be alright for checking the valve gap.
Let me know what the valve gap is.
Eric
