My turn with the 5.8;
this is my favorite engine, I absolutely worship its power to price ratio.......


After using this size and brand for a few years now, I have a new problem, engine will not run at any throttle setting past 30%.

Starts fine, with a flip after choking, idles fine at a steady low pace, will advance on power fine to 30% then dies. No burps, no slugs, just stops running as if the fuel is shut off.

I had the ignition unit replaced, and swapped up to a 1400mah 4.8 volt battery. Any input would be appreciated, as I need this motor to drive my P-40 in 4 days!

Thanks in advance,
Ray

The high speed needle controls fuel at openings over 30%..If it won't run there it's not getting fuel..Try partially choking it..If that works take the high speed needle out and blow it out with carb cleaner, also clean the filter screen....Check the diaphragms, if they're at all "crinkley "they need to be replaced...

Thanks RC,
I did assume something like that, and pulled the high speed needle out, but I blew it out with air, with no effect. I will try your other methods and see if thats going to be the case.

Ray

If it shuts off that fast it might be an intermittent connection at the point where the sensor wire comes out of the mount..Try taking the spark plug out, ground it against the engine, open the throttle and see if the plug fires with the throttle open.....
Remote possibility....

If it shuts off that fast it might be an intermittent connection at the point where the sensor wire comes out of the mounting plate(if the advance is mechanical)..Try taking the spark plug out, ground it against the engine, open the throttle and see if the plug fires with the throttle open.....
Remote possibility....