Small Engines (Lawn Mowers, etc.): Compact Tractor, gutbrod 1050, max rpms

Question
Dear Ben,

I came across this forum and it seems you know an awful lot about these things.

I have A Gutbrod 1050 compact tractor. ( Petrol 1 cylinder 450cc 14hp /12 bhp) Its the same a a Massey Elf.
It seems to work just fine, but as soon as I engage the rotavator, it stalls.
The rotavator spins fine when it ls lifted off the ground and it was working fine a few weeks ago. It is made especially for the tractor.
It works if i pull away in fourth gear but is, of course, too fast to do any rotavating.
I don't believe that the strain is too much for the engine.

Could you perhaps give some suggestion of what it mightbe

Thanks in advance

David

Answer
David
Sounds like you may have a governor problem,the governor works with the engine when there is a load on  the equipment the engine will start to slow down the governor will compensate to bring the RPM'S up to help the engine with the load. In your case the lower speeds need more engine torque & it is not receiving it.
Check the tank to see if it has rust inside. If the tank is rusted, a likely cause for the problem will be the fuel filter and or carburetor problems. IF the engine has been sitting with gasoline in it and a fuel stabilizer was not used the tank and carburetor will need to be cleaned.

IF you can get a good idle on it, go to your high screw and turn it in as far as you can without killing it. Then turn it out about 1/16 turn while you trigger the throttle a couple of times quickly. Each time it tries to die out go out another 1/16 and see if you hit a setting on the high speed that lets it accelerate well. When you hit that setting (hopefully it's there), hold the throttle wide open and turn the screw out to get the highest rpms, then back in until it drops the rpms slightly (about 1/16 to 1/18 turn). Leave it at that setting and go back to the low speed screw, turn it out for max rpms, then back in to drop the rpms.

By going back in after max rpms on either screw you'll be making the mixture a little richer.  the richer mixture will let the engine carry a load.

If you can't get it to accelerate, check the fuel cap for vent blockage, the exhaust for blockage, the air filter, and the fuel for trash or any other debris.