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Cosmo Hitachi carb questions

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Old Sep 11, 2019 | 12:17 PM
  #1  
Seann17's Avatar
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Default Cosmo Hitachi carb questions

I've just finished installing 4 port 13B in '77 AMC Pacer (just for fun). This carb came off about a '76 Cosmo, wondering if anyone has some experience with these to help with a few questions. I've plugged the 2 ports for the oil pump, running mixed fuel. The nipple to the left of the large adjustment screw goes to the distributor. Can all the other pipes be blocked off, including the one one the top on the other side, or are any critical to hook up somewhere? This came to be in a box, never saw the car. Also, the top bracket on the throttle side interferes with the secondaries opening, had the plastic shielded return spring attached, but when the rod (inside the spring) moves up, it makes contact before WOP. Also, the 2 ***** in the accelerator pump circuit, one metal, one plastic...which one goes under the pump, and under the discharge nozzle? Lastly is there a starting point (turns out) on the 2 adjusting screws for initial startup? Thanks for any input,
Seann









Old Mar 5, 2020 | 02:00 PM
  #2  
partlymazda's Avatar
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Default Re: Cosmo Hitachi carb questions

Originally Posted by Seann17
I've just finished installing 4 port 13B in '77 AMC Pacer (just for fun). This carb came off about a '76 Cosmo, wondering if anyone has some experience with these to help with a few questions. I've plugged the 2 ports for the oil pump, running mixed fuel. The nipple to the left of the large adjustment screw goes to the distributor. Can all the other pipes be blocked off, including the one one the top on the other side, or are any critical to hook up somewhere? This came to be in a box, never saw the car. Also, the top bracket on the throttle side interferes with the secondaries opening, had the plastic shielded return spring attached, but when the rod (inside the spring) moves up, it makes contact before WOP. Also, the 2 ***** in the accelerator pump circuit, one metal, one plastic...which one goes under the pump, and under the discharge nozzle? Lastly is there a starting point (turns out) on the 2 adjusting screws for initial startup? Thanks for any input,
Seann




nice car. some may not know that the pacer was supposed to be rotary powered but had to be modified for the straight six when they changed their mind. You are missing a spring to make that throttle latch correctly. it was a safety device. If your throttle spring broke it tripped a cam(the one pictured) and snapped to unlock the second spring. Three springs total primary throttle spring, secondary safety spring and third trip spring (missing) It made the throttle really though to push down so you would know to get it fixed. Difficult to drive this way. The top brass fitting is just a port for cold weather antifreeze starting fluid. It can be left unhooked. There is a check valve to keep the dirt out. You need to find your plugs for the main jet holes too. I would recommend keeping the oil injection hooked up too (very reliable system). I remember these cars coming in with that spring tripped. So hard to push the pedal down. Easy fix to snap it back in place. Push the rod up and latch it into the cam and you can see how it works.
Old Mar 7, 2020 | 03:29 PM
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Seann17's Avatar
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Default Re: Cosmo Hitachi carb questions

Hey thanks for your reply but I finally found at least half a manifold and made the other half to put this on the car (see photos). It's what I wanted from the start. Anyone wants the original carb, they can have it.
Thanks,
Seann


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