1.8 Webber carb problems

Hi all, my 1.8 driver is massively over fuelling to the point its smoking like a chimney and running like a bag of . Ive taken the carb off took out the 4 jets and idle screw, cleaned with carb cleaner and blown out with a high pressure air line. I put the carb back on and set the mixture correct to the manual and it ran like a dream for 5 mins, no smoke but then reverted to the poor running condition again. Does anyone know how to cure this? Thanks for any help

What color is the smoke blueish, or whitish and sweet smelling?

Are your Radiator Hoses being over pressurized, and can't be squeezed when hot.

Will it idle fine, but under load stalls or cuts out?

Why, well Blueish smoke is oil fouling, White Smoke can be a blow head gasket if sweet smelling or condensate that hasn't burned off.

I had a Toyota, that would idle fine, but on the road it would balk, cut out and I couldn't get it over 30MPH.

I rebuilt the carb, and well it still did the same thing.
I dropped the Muffler (Sliencer off) and the car ran great.

Turned the Muffler over and it had rusted out on the top and collapsed internally. (the old Potato in the exhaust pie).  So don't discount excessive back pressure.

Briano1234 said

What color is the smoke blueish, or whitish and sweet smelling?

Are your Radiator Hoses being over pressurized, and can't be squeezed when hot.

Will it idle fine, but under load stalls or cuts out?

Why, well Blueish smoke is oil fouling, White Smoke can be a blow head gasket if sweet smelling or condensate that hasn't burned off.

I had a Toyota, that would idle fine, but on the road it would balk, cut out and I couldn't get it over 30MPH.

I rebuilt the carb, and well it still did the same thing.
I dropped the Muffler (Sliencer off) and the car ran great.

Turned the Muffler over and it had rusted out on the top and collapsed internally. (the old Potato in the exhaust pie).  So don't discount excessive back pressure.

The colour not to sure but definitely over fuelling. Head has been rebuilt and cylinders been pressure tested and all good