- Joined
- Jan 1, 2009
- Messages
- 443
Hi Guys,
Last week I wrote of my troubles getting my new rebuid to start. I got back many great suggestions, most of which I used, but unfortunately, no cigar. Finally, I pulled off the timing cover and checked the gear and sprocket allignment; exactly as stated and shown in the manual. Determined to validate the valve timing, I pulled down Dave Comeau's Mk3 cam profile and superimposed the degree specs from the manual (below).
While setting up the degree wheel, it came to me (slowly, my 60-year warranty has long since expired) while looking at Dave's graph, that the intake and exhaust lifts overlap, and I was (dumbly) setting each side, assuming that when the exhaust valve was open, the intake valve was closed. Clearly this is not the case,and I was grossly over-gapping the valves (the owner's manual states clearly to set one valve when the corresponding valve on the opposite side is open). Since I was already there, I increased the exhaust valves gap to 0.013" and degreed the LHS exhaust valve - dead nuts on. I also checked the rotor marking at 31 degrees BTDC - also spot on. So I closed her up, adjusted the valves THE RIGHT WAY, and pressed the starter. The engine immediately came to life (OK, I used the suggestion of starting spray) and settled into a nice, smooth, slightly quick idle. What a thrill. What a machine.
Last week I wrote of my troubles getting my new rebuid to start. I got back many great suggestions, most of which I used, but unfortunately, no cigar. Finally, I pulled off the timing cover and checked the gear and sprocket allignment; exactly as stated and shown in the manual. Determined to validate the valve timing, I pulled down Dave Comeau's Mk3 cam profile and superimposed the degree specs from the manual (below).
While setting up the degree wheel, it came to me (slowly, my 60-year warranty has long since expired) while looking at Dave's graph, that the intake and exhaust lifts overlap, and I was (dumbly) setting each side, assuming that when the exhaust valve was open, the intake valve was closed. Clearly this is not the case,and I was grossly over-gapping the valves (the owner's manual states clearly to set one valve when the corresponding valve on the opposite side is open). Since I was already there, I increased the exhaust valves gap to 0.013" and degreed the LHS exhaust valve - dead nuts on. I also checked the rotor marking at 31 degrees BTDC - also spot on. So I closed her up, adjusted the valves THE RIGHT WAY, and pressed the starter. The engine immediately came to life (OK, I used the suggestion of starting spray) and settled into a nice, smooth, slightly quick idle. What a thrill. What a machine.
