jpadie
Member
- Joined
- May 17, 2020
- Threads
- 2
- Messages
- 11
Hi
first post here - be gentle! I know precious little about motors, and particularly not the words used for various bits.
I was asked to take a look at a neighbour's Stiga mower (combi 55 with a Honda engine) which was not starting. Engine had compression, spark was ok and air filter was clean. Exhaust was not blocked (which is a common problem here with bees filling anything that looks like a hole). So I concluded it was the carburettor and disassembled it. The float valve was ok but the little pipe from the fuel bowl in to the carburettor body was blocked. Probably with old fuel that had varnished over the winter.
I cleaned this out in an ultrasound bath and then blasted with contact cleaner. The motor then started and worked for a few hours before the revs got lower and lower and then died.
I was not able to start it again. So disassembled the carb again and made sure that the little pipe/tube into the carburettor body was still clear. It was. but still not joy with getting it to start.
I asked a friend to keep trying to start the motor with the pull chord so I could see what was happening with the two baffles in the carburettor (I don't know what they are called but there is one on the engine side and one on the air side, throttle valve and choke valve perhaps?).
I found that the motor would start every time cleanly if i manually moved the engine side baffle so that it was shut (parallel to the engine). But try as I might with adjusting the various springs and screws, I don't seem to be able to get the machine to start without manual intervention. in removing the carburettor the only thing that I changed to start with was the clamp on the choke cable which I initially loosened. I'm fairly sure that I replaced it within 2-3mm of it's initial position. Obviously since then I've wiggled just about everything!
Can anyone point me in the right direction please? happy to provide photos if that is useful.
many thanks, in advance.
Justin
first post here - be gentle! I know precious little about motors, and particularly not the words used for various bits.
I was asked to take a look at a neighbour's Stiga mower (combi 55 with a Honda engine) which was not starting. Engine had compression, spark was ok and air filter was clean. Exhaust was not blocked (which is a common problem here with bees filling anything that looks like a hole). So I concluded it was the carburettor and disassembled it. The float valve was ok but the little pipe from the fuel bowl in to the carburettor body was blocked. Probably with old fuel that had varnished over the winter.
I cleaned this out in an ultrasound bath and then blasted with contact cleaner. The motor then started and worked for a few hours before the revs got lower and lower and then died.
I was not able to start it again. So disassembled the carb again and made sure that the little pipe/tube into the carburettor body was still clear. It was. but still not joy with getting it to start.
I asked a friend to keep trying to start the motor with the pull chord so I could see what was happening with the two baffles in the carburettor (I don't know what they are called but there is one on the engine side and one on the air side, throttle valve and choke valve perhaps?).
I found that the motor would start every time cleanly if i manually moved the engine side baffle so that it was shut (parallel to the engine). But try as I might with adjusting the various springs and screws, I don't seem to be able to get the machine to start without manual intervention. in removing the carburettor the only thing that I changed to start with was the clamp on the choke cable which I initially loosened. I'm fairly sure that I replaced it within 2-3mm of it's initial position. Obviously since then I've wiggled just about everything!
Can anyone point me in the right direction please? happy to provide photos if that is useful.
many thanks, in advance.
Justin