Im lost

[poppagonk]

I just got an ASP 91 four storke and i can't get it to run very long. i have been in rc for a long time but i have never had a four stroke. this one doesn not have a fuel pump so i know that is not the prblm. i wondering if anyone can tel me where the low end ajustment is. I don't know if i just am dum or what i just don't see it. if anyone has a pic of where it is that would be great cause i think that is y it wont run very long. and i did not get this new i got it from a sale. so if someone can help that would be great.

[ivanc]

The low end adjustment screw is in the center of the throttle barrel, throttle lever side - look in the middle of the throttle lever and you'll see it. It's made of brass.

Ivan

[Chip01]

You did not give us enough information. "Does not run for long" could mean a lot of things. How long is "long?" Will it continue to run with the glow plug lit up by a battery? Or is it fuel starvation? Could it be a tank location problem? Could it be a hole in the fuel line? Could it be that the pressure tap on the muffler is not hooked up to the pressure port of the tank? Could the clunk be stuck in the top of the tank? Could be pressure line and fuel feed line be crossed?

Is the engine new? What do you have the main needle valve set at? Should be 1.5 to 2.0 turns out, preferbly two turns if the engine is new. Do you have the throttle set to low, it has got be open a little bit to run, something above idle but way less than max.

What size prop? Should be about a 14 X 6 for starters.

Have you checked the valve clearances? They should be set at room temperature. The clearances are .04 mm to .10 mm (.0015 to .004 inches). Get some feeler gauges from the auto parts store. Set them at top dead center (TDC). There are two times TDC occurs, do it on the one that does not move the valves (otherwise known as the power stroke).

Give us some more information and we may be able to give you good advice.

Is the vent on the back plate clear? It has got to be vented unless it is one of the newer engines where the vent is up front near the cam and is ported to the intake manifold.

Cheers,

Chip