Sgt. Howard
Active Member
... also known as the 'High Speed' carb- this is the one found on Grubee 'China Trollop' kits, it has a hose breaking vacume between the filter and the throat plus the nylon insert mounting it onto the intake- I've heard mixed reviews on this device and have to admit the four that I have mounted have been a bit of a ... challange... until I've solved three main issues;
1) that CHEEZY nylon insert/sleeve/bushing- pulled dimentions off the carb, off the intake and off the ... piece of rubbish... and cut one out of thick walled 1" aluminum tubing. If this thread generates interest, I'll post the dimentions for those with a lathe
2) that stupid rubber tube from the air cleaner space breaking vacume to the venturi... remove the filter, insert a fitting screw into the tube where it inserts into the cleaner and put filter back.
3) open up the throttle handle- notice the white nylon stop that prevents the handle from allowing a low idle. This is not an accident- with an ultra lean mix (remember the tube and the leaky nylon bushing?) the only way to keep the engine running AT ALL is to shove it up to near throttle wide open... shave off about 1/4" of the white nylon stop and re-assemble... then screw the turn channel under the handle as far into the handle body as it will go. This ought to allow you to drop the idle to something more reasonable...
The idea behind what you encounter in this carb is simple- running lean produces less smog. It looks good on paper. Unfortunately it also cooks your engine and grinds your bearings. Typical California requirements. Fitting the screw as I have described leaves you with a tube that outwardly looks to be correctly installed but in fact is plugged. The nylon bushing will eventually turn into cottage cheese no matter what sealant you try to use- with the aluminum bushing, there is no leak or wobble. Lowering your idle to what will work with the other two issues solved gives you more throttle control and better engine life. With all three issues dealt with... THIS CARB ROCKS!!!! POWER UP THE KAZOO!!!
How does this check with other's experiances?
1) that CHEEZY nylon insert/sleeve/bushing- pulled dimentions off the carb, off the intake and off the ... piece of rubbish... and cut one out of thick walled 1" aluminum tubing. If this thread generates interest, I'll post the dimentions for those with a lathe
2) that stupid rubber tube from the air cleaner space breaking vacume to the venturi... remove the filter, insert a fitting screw into the tube where it inserts into the cleaner and put filter back.
3) open up the throttle handle- notice the white nylon stop that prevents the handle from allowing a low idle. This is not an accident- with an ultra lean mix (remember the tube and the leaky nylon bushing?) the only way to keep the engine running AT ALL is to shove it up to near throttle wide open... shave off about 1/4" of the white nylon stop and re-assemble... then screw the turn channel under the handle as far into the handle body as it will go. This ought to allow you to drop the idle to something more reasonable...
The idea behind what you encounter in this carb is simple- running lean produces less smog. It looks good on paper. Unfortunately it also cooks your engine and grinds your bearings. Typical California requirements. Fitting the screw as I have described leaves you with a tube that outwardly looks to be correctly installed but in fact is plugged. The nylon bushing will eventually turn into cottage cheese no matter what sealant you try to use- with the aluminum bushing, there is no leak or wobble. Lowering your idle to what will work with the other two issues solved gives you more throttle control and better engine life. With all three issues dealt with... THIS CARB ROCKS!!!! POWER UP THE KAZOO!!!
How does this check with other's experiances?