QuestionI have a '87 samurai w/ a rebuilt engine and carb. Do you have a pic of the choke vacuum cut off diaphragm?
AnswerI don't have any carb stuff, sorry.
However, I can describe the major problem with those carbs.
The water heated "wax pill" type element usually applies the choke too much, and for too long.
At the bottom of the piston is a screw in a crimped and sealed section that bears on the lower end of the wax pill piston. You will have to take the carb off and turn it upside down to see this clearly. If you use a hairdryer to heat the wax pill area, you can see it's function, and everything else will become clearer.
Disassemble that, and find a slightly longer replacement screw ( I think it's 4mm x 0.8)that will allow you to set the choke so it's not applied so heavily.
Next find the fast idle linkage, and set the fast idle speed to somewhere in the 2000 - 3000 range cold.
You'll find that the choke pulloff is not particularly effective, if you don't make those adjustments first.
They are deviations from the factory settings that work well at altitudes up to 10k ft and temps down to -30F. You can lower the fast idle somewhat at altitudes below 5k, but this works, and the factory settings are essentially only good for sea level, and moderate temps.
One thing to be aware of is that as they age, the wax pill looses some of it's "stroke", and as a result, applies the choke more and for a longer time, necessitating replacement of the adjusment screw with something that's adjustable.
This is the primary issue that causes Samurais to run way too rich in warm up, and for twice too long, consequently diluting lubrication on the rings and piston skirts, and causes the engines to have severely worn pistons/rings at lower than normal mileages.
