carb picture..please help

[Roman Tasel]

some of you guys probably know i have been having troblems with my hitachi carb. here is a picture:

 

 

 

a-quick idle screw

b-mixture screw?

c-idle selenoid? (next to valve cover)

d-throttle adjusting screw?

e-choke

 

The other selenoid with the white wire connecting to it is the anti deisel selenoid right? I heard that if that is not working, your car will run without the key inside ignition.

Edited January 16, 2009 by Roman Tasel

[RacnJsn95]

I've never heard that...

[datzenmike]

Not a mind reader, had to look up your profile. Assume it's for a '74 620?? Picture not working either.

 

Check this post again for wire colors and what they go to.http://forum.ratsun.net/showthread.php?t=9020

 

The Idle cut is a hexagonal thing (usually with a Red wire) at the rear of the carb on valve cover side and above the throttle linkage.

 

The electric choke is just beside the idle cut solenoid and is black and round with usually a Blue wire.

 

The BCDD cut solenoid is at the rear of the carb furthest from the valve cover and screwed into the BCDD. May have a white wire.

 

 

 

 

IN THE ABOVE PICTURE

 

RED wire idle cut solenoid.

 

Round black thing behind RED wire, is the electric choke.

 

BCDD cut solinoid not shown

 

Idle mixture screw is below large spring. It's the screw with small spring wrapped around it.

 

Idle speed screw is a few inches over to the left and partially hidden by linkage. It's another screw with spring around it.

Edited January 16, 2009 by datzenmike

[datsunaholic]

The Idle cut-off solenoid and the Anti-Dieseling solenoid are the same thing. The white-wire one is the BCDD cutoff solenoid.

 

The anti-dieseling solenoid simply cuts fuel to the idle circuit to prevent dieseling, which is caused by fuel igniting by heat instead of being ignited by the normal spark. The spark turns off as soon as the ignition is shut off, but sometimes the engine will sputter a bit before dying. It's also called "run on". It's not a normal run, it kicks and sputters and sounds like hell, and it's really common with carbonned-up engines.

 

Not all carbs have the solenoid; in fact while it's common on the '73+ Datsun carbs, most earlier ones didn't have one at all. It's rare to see a Weber with one (I have 5 webers and only one has the anti-dieseling, AKA Idle cut-off solenoid). However if the carb has one you need to keep it hooked up or the car won't idle at all.

[ggzilla]

Yes, my Datsun keeps running (slowly and irregularly) indefinitely after I turn the key off. It's called "dieseling" and is the problem that the Anti-Diesel (idle fuel-cutoff) solenoid fixes. In older cars you just set the idle low enough (500-600 RPM) and there is no problem. With the '70s emission controls and higher idle speeds it was a real problem.

[650savag]

Do what I do on both of mine. I have learned to turn the ignition off with the truck in gear, and with one foot on the brake and the other on the clutch, just release the clutch at just the right time and it will die without a whimper. (no dieseling). After a time or two, you will get the feel.

[datzenmike]

Exactly. My Dart had 10.5 compression and would diesel on shut off. It didn't have idle cut but it did have a solenoid that the idle setting was adjusted against. When the key is turned off the solenoid drops and the throttle plate snaps fully shut. By the time I figured it was never set right at the factory I was using the clutch and just left it.

[primo74620]

Does anyone know where I can find a Idle cut off solenoid?????

[datzenmike]

More info needed... is this for a '74 620??? Easiest would be off an old carb at a wrecking yard. You have an L18 but the newer more common L20B solenoids would be the same car or truck.