The hidden secrets of the carburettor revealed. It was as bad as I thought it might be and again evidence of the bike being a long term non-runner.
Whilst working on the engine, I’d resisted the urge to have a look at the carb, knowing that the time the bike might have been standing and not run was going to have an impact. And, yeah taking of the float bowl showed the extent of the dreaded yellow gunge, solid in places. The carb is a -28 Del’Orto, which is slightly larger than the -26 carb from the TL320.
Stripped down the carb, by removing the float bowls, main and pilot jets and then sprayed lots of aerosol carb cleaner. I used an airline and some paint-spray cleaners to work on the jets. I then went round and did it again.
Cleaning out petrol residue must down as the worst job for with any bike.
The main problem with was with the float valve needle, where the spring loaded rubber end cap was damaged. After assembling and fitting the carb, petrol just flowed through, so the float valve wasn’t seating properly. I had a spare one from a smaller 26 Del’Orto carb, so swapped that in and this then cured the problem. I didn’t adjust the float valve height and kept it as is, as once the bike is running I can then look at tuning the carb if needed.
The airbox, carb hose and inlet manifold were also checked. The airbox has seen some action and has felt the effects of the exhuast midbox. I used some silicon sealant in the largish cracks and filled in the holes. It looks like the original top of the airbox is missing, as the metal cover has has some rudemetary holes drilled in it and doesn’t look like the finished article on the TL320.