Carbi Problems ?

[cookie monster]

Recently the zook has been running poorly, lacking power, wont pull over 80kmh, higher than normal fuel consumption, exhaust staining the garage floor black.

Today I pulled the plugs out and they were ok for the gapping, but I think they were showing that the engine is running lean / timing out, as they were quite white, with no deposits on them.
This led me to have a look at the carbie and it seams that the second buttterfly of the std carbie is not opening at all. Does the second butterfly open mechanically or by vacuum, as it appeares to be connected to a vacuum type device ?

I think this could be the reason the engine seams down on power and running lean ? What do you think ?

The engine is the G13A 1324cc, recond head, std carbi, new plugs & leads.

cheers

cookie monster

[Santos]

vacuum operated, and they wont open if your rev it stationary
replacing all the vacuum hoses and a good dose of carbi cleaner might be an idea

not saying that it isnt the carb but check other things before blaming the carb

i know a poor carby hat seal was costing me power and fuel economy for a while as it was sucking hot air , a block fuel filter reduced my flow etc etc things around the carb especially

[topdown]

Had a similar problem on mine, I worked out the automatic choke wasn't working properly it wasn't opening fully after warming up and also taking ages to open on starts. The car would idle erratically and flood if I braked hard at lights plus leave a black stain on the garage floor from the exhaust on start up.

I just removed the choke all together.
Starts and runs like a dream now. Starts better on cold days than it did with the bloody choke too.

I would also check your dizzy and coil though mine was missfiring and losing power when I first bought it so I put new spark leads, points and a coil in it and it made a huge power difference.

[dank]

Check mechanical fuel pump as well. Make sure its flowing properly. If this isn't working properly then it can make everything else down the line seem like its faulty. Cheap to replace $70 odd dollars...

[RockHopper]

They are actually mechanical secondaries, but are vaccuum actuated. To see if they are opening, with the top cover off the carby, give it a rev and smother the top of the carby with your hand to restrict airflow. You should see the acuator pulling up and the secondary linkages working.