OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Trimmers and Brushcutters McCulloch Trimmers & Brushcutters MC Culloch proscaper 11-HD

I`m opening a new thread, as my post " adjusting screws brushcutter" MC Culloch proscaper 11-HD is closed, as i thought i had it solved after the new kit-plug-air filter-fuel pickup filter-checked the exhaust port-cleaned the petrol tank-got new fuel-cleaned the fuel cap vent. Now it`s up to it`s old tricks again, because, it starts and idles, but when i pull the trigger it stops and also sometimes it will stop without pulling the trigger. Could i ask for further advice please?

The manufacturers seem to recommend that you make the idle richer than it would be to give the best idle quality, because of that problem. I suggest you try readjusting the idle mixture (low speed mixture screw). Recheck that what you have gives the best-quality, fastest idle, then turn the screw anticlockwise up to an eighth of a turn, speeding up the idle when you do it so it runs fairly smoothly (though it will be four-stroking). The clutch may not disengage, because the speed will have to be a bit higher than before to keep it running stably with the rich mixture. Then run it flat out and adjust the high speed mixture for the fastest speed, then turn it anticlockwise until it just starts to four-stroke. That makes it a bit rich on the slow-down when you release the throttle, and gives it some chance of not stalling.

Welcome to the world of two stroke brushcutters.

I started from scratch and turned the "L and H" to seat gently and then turned the "L" anticlockwise one and a quarter back and the "H" one full turn anticlockwise. Believe it or not (i said) the thing kept running for about five minutes without revving and stopping. I restarted it three times and it jumped into life and kept running. The cutter head doesn`t stay still all the time and i adjusted the "L" screw a little and didn`t do much with the 'H" screw. I really don`t know what i did, but everything crossed, i hope it keeps working. I`ll try it again later and keep you posted.

Thanks for keeping us posted terrace. I think your reports are generally in line with my own experience - tuning those things is more or less a black art. I've found some of the same issues with chainsaws, but the bigger engines seem to be easier to tune. If you keep the fuel clean and store them with the carburetors empty, not much goes wrong. I did have one chainsaw that was always hard to start, and the best efforts of a mower shop didn't make it any better. I donated it to someone who didn't want it either - it was accepted because I included a much better saw in the deal.

The moral is, small cheap two strokes with big carburetors are a pain in the backside, but they needn't be unreliable, just nasty to operate.

I`m pleased to say that my Brushcutter still starts when i want it to. A lot of perserverance to get there but also with your fine advice and assistance. Thank you heaps.

Thank you, for letting us know the outcome. It is way better for our archives if cases have conclusions, rather than just petering out without any feedback. I'll close this thread.