Ok, so the truck is a 1986 K20 with a 1989 350 (carbeurated). The engine originally had the timing mark at 12 oclock. I started having trouble with timing when the chrome dist hold down clip started not holding the dist in place. I thought there was something wrong with the 40°BTDC so I got a summit balancer with all the marks on it, designed for the 2 o clock position, and put a timing tab off the side of the timing chain cover (also at the 2 oclock position), hoping this might explain the problem.
Quote:
Originally Posted by geezer#99
How did you determine that zero on the balancer is at tdc?
|
I took the cap off the dist, pulled #1 spark plug, and took drivers side valve cover off. I had someone turn the crank from the bolt inside the crank pulley as I watched the dist. It was 180 out (which I already knew), so when the button got to about 9 o clock on the distributor, I started feeling in the spark plug hole with a dowel rod, and could feel the piston coming up. Once it stopped and started going back down, I turned the crank the opposite direction until I felt it was at the top. The timing tab lined up almost perfectly with 0 on the balancer. I verified that both valves were closed on #1, so I knew it was on the compression stroke.
At this point, I took the dist out, marked the dist base with the cap for #1, and put the dist back in the engine so that the button pointed right before (counter clock wise of) the (real) #1 mark. Then it wouldn’t fire at all. This is when I started moving the dist a tooth and finally got it to fire again.
Timing light is reading 40 at about 700 rpm with vac advance plugged.
Thanks.