My mower wouldn't start this year and I guessed it would be congealed oil some where. I took the carb off and soaked it in neat petrol and blew out any muck I could see, took off one cover and cleaned but left the diaphragm as it was stuck on solid and didn't want to damage the seal. Put it back together and it started only to die soon after. If I start it and keep gently pumping the primer it will run, as soon as I stop it stops. If I pump the primer when the engine is hot but not running running it sounds as if the fuel is going straight into the engine and hitting something hot as it sizzles. Have I missed some blockage or have I put the spacer between engine and carb on the wrong way round, or some other silly mistake?
Does anyone have an exploded diagram of the carb?

Gary, April 2010

Anyone been able to source a replacement primer bulb?

info appreciated

Thanks

Chris

Chris, August 2021

quite simple this one, you need a new diaphragm pump and metering.
the hot sizzling is the fuel hitting the red hot piston.
again andy marsh all one word at ntlworld dot com
you could well have the spacer the wrong way up and wrong way round!!

andy marsh, July 2010

Gary, My L400 had exactly the same problem - roaring away all the time I pressed the primer bulb and stopping as soon as I let go. I eventually noticed a small hole in the primer bulb letting air in. As soon as I sealed the hole the engine ran fine.

Robert, May 2010

I would also like an exploded diagram of the carb including the air filter assembly. Does anyone know where I can obtain the three parts of the air filter assembly, the flange, cover and dry paper cartridge filter?

Thanks.

Sandra

Sandra E Chubb, May 2010