Bextreme04
Full Access Member
- Joined
- May 13, 2019
- Posts
- 4,464
- Reaction score
- 5,630
- Location
- Oregon
- First Name
- Eric
- Truck Year
- 1980
- Truck Model
- K25
- Engine Size
- 350-4bbl
Am I seeing that timing tab at 12 o'clock? For some reason mine is at about 2 o'clock. This could be the problem?
Yes, as stated earlier in this thread, you need to verify mechanical TDC for the #1 cylinder to make sure you have the correct timing tab for the harmonic balancer you are running. Basically you put a special plug in the #1 spark plug hole and turn the engine over clockwise by hand until the piston makes contact with the plug and stops. You then put a mark on the harmonic balancer where it lines up with 0 on the timing tab. Then you turn the motor over counter clockwise until the piston makes contact with the plug again and stops. Then put another mark on the balancer where it lines up with 0 on the timing tab. Halfway between those two marks is the actual mechanical TDC of the #1 cylinder. If the cast in mark on the balancer is halfway between those marks, then everything is correct. If the cast in mark is pretty far off, you likely have the wrong timing tab(i.e. 12 o'clock instead of 2 o'clock or vise versa)