Mikuni carburetor

[xboxrox]

The auto choke release assist will also cause internal vac metering issues when they fail. This gadget is like $35 AUD by itself (when you can find one)

GOOD POINT geezer..!

Maybe (?) vacuum metering issues could be caused if any software part under vacuum were to leak (?) (O rings diaphragms valve disks vacuum hoses etc...)

Ordered a new choke breaker diaphragm from ebay: https://www.ebay.com/itm/333644647956

So far these software items leaked vacuum in my original carbydisassembly visual inspection, vacuum test & engine operation confirmed):

1) Secondary throttle actuator depression chamber (did not open the secondary butterflies)
2) Choke breaker pull off diaphragm (rottened, did not operate the choke butterfly)
3) Three of the four DSV ESV JSV selenoids had broken O rings (not sure the effect)
4) The BVV bowl vent valve O ring (totally shot 'n gunked up the BVV diaphragm)

Guess what..? After installing the PicknPull J/Y 1985 Mikuni carburetor; one of the first things I noticed was a dramatic increase in braking power..! Do you suppose all these leaking parts on the carb affected the amount of vacuum assist on the braking system..? Something caused the seat of my pants (foot) to feel a noticeable difference in ease of pedal pressure needed for breaking... That J/Y carb more than likely has a good secondary throttle acutator depression chamber because that carburetor caused the truck to have a new thing; passing gear..! Buwaaah..!

Your Thoughts Anyone (Good Catch geezer )