chris-s

I've just purchased a part-built model that has a ZDZ40 fitted up front, not sure of the exact model tho it has a blue head. It's my first gas motor, there are several gas motors in my local club so general help should be ok, but is there anything specific I should know about this engine? I belive the engine has previously run in another model.

Fuel/oil mix?

Cheers

Chris

Oilsands

I have a ZDZ 80 RV, so some of the stuff is simular. The oil/gas mix that is recommended is 40:1 after break in and premium gas. RC Showcase www.rcshowcase.com has some information on ZDZ engines, such as how to set the timing, adjustments of the H and L needles, etc. Also good source if you have any problems. Since it has an alumium head, get some never seize (high temp) and put a little on the spark plug threads. Do not over tighten the spark plug (only requires 7 ftlbs of torque) or remove it too many times, this can pull out the threads. If you do pull out the threads, you can purchase a tool and inserts to repair and get you flying again. They have a starting procedure that seems to work well, it is 5-5-1. That is with throttle at full open, ign off and choke on, flip the engine over 5 times (may need to flip over a few more time if the fuel line was dry), then with throttle at full open, ign off and choke off, flip the engine over 5 more times, then with throttle at idle (or 1 to 2 clicks above idle), ign on and choke off, flip over once and it should start. As with any gas engine, never run the engine lean. When setting the H needle, adjust to max rpm then back off to drop rpm down aprox 200-300 rpm. Setting the L needle, adjust a little at a time till you get a go transition between idle and full throttle, then recheck the H needle (as adjusting the L needle affects the H needle setting).