Motorcycle Repair: 91 Kawasaki ZX6 - Not starting, engine cranks, vacuum hose

Question
I just finished adjusting the valves, and setting the timing. I drained all the fuel before doing this as I took off the carburator. Now I cannot get it to start. I have fuel in the fuel filter and spark. The engine cranks well (no unusual sounds). When I checked the spark plug for spark it was dry. Do I have to prime the carburator?

You help would be appreciated.

Thanks,

Nate

Answer
Hi Nate,

The carburetors do not require priming. However, some petcocks have a "PRI" (prime) position for bypassing the vacuum positions and refilling the float bowls after servicing the carbs. Otherwise, keep the petcock in the "ON" or "RES" positions accordingly.

Check for fuel in float bowls by loosening a float drain screw slightly.

Check petcock positioning. Try switching to "RES" (reserve).

Check for a pinched fuel or vacuum hose.

Check that the vacuum hose from the carbs to the petcock is attached.

It all above checks out ok, remove spark plugs and check cylinder compression of all cylinders. Add a teaspoon of oil to each cylinder and hold throttle wide open during testing. Adding oil will help seal the cylinders on the cool engine.

If compression readings are low or zero, the cams are likely out of time, and/or the valves have excessive clearances.

Respectfully,
Mark Shively