Help,
I purchased a 94 mach1 670 engine, I was told it ran fine, I put it in and it starts and idles, it just will not rev up. It spitts sooo much gas out the carbs it is running out of the airbow, I've cleaned the carbs, switched plugs with new ones, tried a differant CDI, also it seems that there is a lot of oil coming out of the exaust, the jets are stock in size and adjusted per the SD manual, I'm thinking Rotary Valve timing???
Thanks
Gutz

check everything, and yes try the rotary valve.

1994 Mach 1 670 rotary valve P/N 420924500. Timing is 144 degrees opening - 72 degrees closing.

Hey,
Do the symptoms fit a miss degreed valve timing?? I'm going to check it tomorrow, I have a degree wheel and with some luck....
Thanks
Gutz

It was the rotary valve, 180 degrees off, now it revs to the heavens.
Thanks
Gutz