Somethings not right?

[scouttster]

I got the 3A motor and got the spark plugs out. I'm manually cranking it with a wrench and I notice the 2nd and 3rd piston coming up to TDC at the same time.. Should this be? Blown bearing? Thanks

[sdoan]

That's the way it's supposed to be. The cranks are made so 2 pistons are going up while 2 are going down, this helps with balance. You will find that 1 and 4 will come to the top at the same time too. If you pull the rocker cover and look at the valves you will see that one cylinder is at TDC with both valves closed (firing) and one is at TDC with at least one valve open (between exhaust and intake strokes).

Blown bearings make lots of noise.

[scouttster]

Confused for a sec.. Thanks for the clarity..