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Ok I’m confused. I was going to measure for pushrod length this evening but I had trouble getting the lifter on the base circle of the cam. I removed all spark plugs and both rockers on cylinder number two. It was tough rotating the crank with a wrench but I was able to do it, the problem I was having is that I never could feel the pushrod on the exhaust valve opening. I rotated the crank several turns but never could feel anything... what the heck?
Why cylinder #2?
If you rotate the crank with a pushrod on the intake lifter, once the valve opens and then closes you are about 1/3 turn from TDC on the firing stroke of the cylinder. If you have an extra set of hands, have them push on the pushrod while you turn. Otherwise, when the pushrod comes up and stops, turn a bit and then push down on the pushrod and you will hear it contact the cam. Keep turning and then pushing down on the pushrod. Once the intake stops moving down you track the piston until its at the top. It can be off a bit because there is no valve motion for quite a bit of crank rotation before and after TDC.
Why cylinder #2?
If you rotate the crank with a pushrod on the intake lifter, once the valve opens and then closes you are about 1/3 turn from TDC on the firing stroke of the cylinder. If you have an extra set of hands, have them push on the pushrod while you turn. Otherwise, when the pushrod comes up and stops, turn a bit and then push down on the pushrod and you will hear it contact the cam. Keep turning and then pushing down on the pushrod. Once the intake stops moving down you track the piston until its at the top. It can be off a bit because there is no valve motion for quite a bit of crank rotation before and after TDC.
Cylinder 2 was the easiest to access while turning the crank by myself. I will get a buddy to assist today and give it another shot. I have never manually turned a motor over before and I was just a little nervous about breaking something. I was able to get a standard 1 1/16 wrench on the crank bolt enough to turn it but it’s not fully on the bolt because the balancer gets in the way, I was a little nervous about stripping the threads.
I assume all the spark plugs are out. If you are worried about stripping the crank bolt threads, not an issue since you will be turning in the tightening direction of the threads and the bolt is already preloaded and won't move. Have your buddy gently push down on the intake pushrod and he should be able to tell when it opens then closes. You can use a straw or something to feel for the piston to some up to TDC about 1/3 turn after the valve closes. I have a small borescope for my iPhone that I can use to watch the piston, which is an inexpensive but very useful tool to have in your toolbox. I have even used to to look down the sink drain when someone thought they dropped a ring
Last edited by vettenuts; May 25, 2019 at 07:40 AM.