hitachi carb fuel flow on / off valve ?

[i need help & guidance]

what part of the hitachi carb shuts off or stops the flow from  the fuel coming in to engine bay from the fuel piping under truck from the fuel pump sending unit

 

once the gas gets from fuel pump and piping and up to the carb and enters the carb. --- what part of the carb itself - has the cut off or stop of flow mechanism in it.?

 

is the stop flow valve = the pin push spring thing that the sight glass float swings up to , when float bowl is full or is there a vacuum activated device some where else inside carb .

 

basically,  i want to know ,,, what part of the carb acts like the ( sort of mechanical toilet fill valve) and stops or slows or cuts gas flow from pump on / off inside the carb.

.

 

only the carb.

 

 

Edited December 18, 2018 by i need help & guidance

[Roadster-ka]

Yes, the valve is called the needle and seat, and the float shuts off the fuel when the level is correct. Also, there is a screen around the inlet. If you need to replace it, remove the rubber fuel hose, then while holding the base, take off the small cap to remove the inlet pipe. Then you can unscrew the needle and seat from carb top.

[banzai510(hainz)]

sometimes by tapping on this will cause it to work. if you see the float glass is empty. Tap on it while cranking the starter it might start to fill. I had this proplem. I eventually went to a Weber carb

 

If you have a later Nissan there is also a Idle cut off on the carb which car/truck will run above idle cause your using the main jet then once at idle you use the idle circuit and if wire is pulled or no 12volt the needle will fill the hole thus plugging gas from going in the idle circut

Edited December 18, 2018 by banzai510(hainz)

[i need help & guidance]

this is a 1982 nissan 720 king cab 2.2 l z22 

 

 

on a side note.

 

indirect comment..

 

 

 

i had read of a relay which requires re-soldering ,

this relay is located in cab under dash

 

but after taking dash apart and removing other relays.

 

my truck does not have this badly designed relay up under passenger side dash area

 

not sure it the relay is even in my year truck,

but i know it is not under dash on passenger above the other 2 relays and vent work.

cause i took all that off and there is nothing there

link

Edited December 18, 2018 by i need help & guidance

[datzenmike]

I can guess what relay you mean but why are you looking for it? There's no need to solder this relay unless it's not working.

 

I think only the later Z24 engines used it not the Z22..

[DIY 1985]

Did you replace your fuel pump?  Fuel filter?  The relay for the fuel pump is controlled by a oil pressure switch, so that in the event of an accident, or no oil pressure, the stalled motor will turn off the fuel pressure.  I believe that the windshield in my rig is leaking rain on the factory relay.  A PO wired my pump by tapping into the ignition-hot circuit.  I can hear my pump when the ignition is on but the motor is off.

[datzenmike]

On 12/18/2018 at 7:11 PM, datzenmike said:

I think only the later Z24 engines used it not the Z22..

 

I would advise only replacing what does not work or proven to be not working. Replacement parts are generally poor quality and worse than an old working condition part. NEVER throw an old part away. Keep as a spare or for parts. The fuel electric pump is mounted on the outside of the frame just forward of the passenger side rear tire. You should easily be able to hear it buzzing if working. The bottom of the pump twists off to get at a fuel filter inside it. If the electric fuel pump is working leave it alone. 

[i need help & guidance]

i got a few things wrong during reassembly process ,

and it caused fuel supply from fuel pump to be shut off .

once i corrected blunder.  engine runs  like it supposed to

here is before i did anything ,

[i need help & guidance]

here is with sight glass off in order  to clean bowl

 

[i need help & guidance]

here is where i learned

i had accelerator pump spring in upside down .

after reading through instructions over and over 

i learned the correct side of the spring has to rest down in carb .

the straight part of spring holds a tiny bearing in place above a jet down under pump

Edited December 27, 2018 by i need help & guidance

[i need help & guidance]

the spring sits down in jet notches

like a flat blade screwdriver would

and holds a tiny chrome bearing in place in center of jet

[i need help & guidance]

here i put sight glass back on upside down

and this caused me to think i had float adjusted wrong

because as soon as i turn key on

gas filled fuel bowl level up , right past sight glass center line dot ..  ☹️

[i need help & guidance]

i had trouble getting old fuel bowl fill valve out

because a socket or wrench would not fit .

so i used a crow foot and a Allen wrench together . .  to get old poor-functioning valve out and to install new valve

Edited December 27, 2018 by i need help & guidance

[i need help & guidance]

while i had fuel bowl fill valve off

i removed other end of fuel line hose at fuel  pump discharge side , back by gas tank under truck

then  put compressor air hose at this end

and blew out rust from lines before reconnecting  new fuel bowl sight glass valve

Edited December 27, 2018 by i need help & guidance

[i need help & guidance]

the other thing i did after correcting all the stuff had put in upside down .

i added a crimp connector spade terminal thing to the top of accelerator pump  .(see crimp sticking out under linkage bracket )

 . .  why.? after adjusting the pump set screw on the carb linkage a few times

i noticed each adjusting  i did , only allowed the carb throttle linkage to hold the pump down more and more , giving me  less fuel not more

.. each pump squirt gave me less and less gas per press of throttle.

so to stop the pump from being held down by the linkage too much (even fully open)  i just set a crimp connector on the top pin of the pump to stop the pre-spring section of the pump from losing any pump range .

it did not solve the issue of cutting out while accelerating by 100% . . . . but it made it nearly go away.

 my next thing i am going to do

is buy another pump assembly and stretch the pump spring some , before i install it

to see if that keeps the pump in full height it needs... so i wont need the crimp spade thing ....

in order to deliver a solid squirt of gas when needed.

 

Edited December 27, 2018 by i need help & guidance