A few questions about the 2F Engine Carburetor, Choke Breaker and Vacuum ports...

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Jun 6, 2012
What is the plastic vacuum hose thing in the bottom left of the picture and why should I keep it there?

I have just received my new 2F carburetor in the mail :p
The old one does all sorts of strange things, the worst of which is idling at 4000 RPM at random times which makes it horrible at traffic lights and down hills where engine braking is needed.

After looking at the two carburetors side by side I noticed some differences:

Firstly there is an extra vacuum port on the old carby which isn't there on the new one (pictures 2 and 4, figure 1*).The one on the right connects to the distributor which regulates the timing. The extra vacuum port on the old carby (the one on the left) is connected via a hose (the one I photoshoped red with the artistic skill of a blind nun) to a strange plastic thing with two wires leading somewhere and another vacuum hose which leads to... another vacuum port?? on the manifold.
I have disconnected all of this with no ill effects aside from the two vacuum leaks. (What and why is it?)

And secondly the diaphragm and levers which make up the contraption called the "Choke Breaker" (see pictures 1 and 3 figure 2*) are non-existent on the new carburetor. Looking at the user manual, this is a standard feature of the OEM carby.
Although I still don't really understand what it is or why it's there, a little googling tells me that the choke breaker is not strictly necessary if you use the manual choke properly. It also seems to have something to do with emissions laws.

On my old carburetor this "choke breaker" is disconnected from the vacuum (the blue hose in picture 3 is blocked off with a bolt in the hose). However when I connect its vacuum hose to one of the aforementioned seemingly redundant vacuum ports, the choke breaker appears to work (that is to say that when the FJ45 is running with the choke on full, the choke breaker keeps the choke half open, (why not pull the choke on halfway?).
Whatever it does, useful or not, it does work so I could just put it on the new carby and attach the vacuum hose to the vacuum port that is currently attached to the strange useless plastic thing.

Which begs the question: What is the plastic vacuum thing in the bottom left of the picture and what do I do with it?
Your engine and carb is a 3f and the new carb is from a 2f engine. What year landcruiser do you have
It is a 1981 FJ45 with a 2F engine.
...at least the head says its a 2F engine...
I only recently bought this Landcruiser and I am fairly new to it all so I don't know.
When I got the rego transferred they said that the engine had been changed at some point (the old owner failed to mention that...)
But it looks like a 2F and everything else is standard... so I think it probably is a 2F.

Now that you mention it, the old carby is actually a 3F.
I hope the manifolds are the same for each...

So what will I assign last remaining vacuum port to? The little plastic thing which does nothing on an FJ45 or the useless choke breaker which may or may not be standard on a 2F?
I think it could be an EGR solenoid, can anyone confirm this? If it is, it doesn't seem to be set up properly.
Pictures are a little muddled on my PC, but--Pic #1 shows an orange circle around the airhorn screw. Pic #2 shows what appears to be the idle mixture screw(brass). Pic #3 shows(I think) the choke breaker diaphragm with a blue tube that terminates somewhere below the pic area--I think it should go to the vac port on the air horn.
Pic #4 shows what I think may be a vac line to the EGR(as Great Scott says)---although it may go to a VSS -- Is this a Ca rig?
Look at the secondary diaphragm-it has a decal on it with the carb number--that would help you id it for sure, then you could look up the carb details on ToyoDIY.com.
I didn't find out what it was, but I installed the new carby without it and it works perfectly. So whatever it is, it obviously doesn't need to be there.
The plastic box is the emissions vacuum "computer" and looks like this one was being used to control the choke beaker, built like you said the troll hole carb does not have one, if you hadn't figured it out, the small nipple on the base of the carb towed the valve cover goes to vac advance for the dizzy,

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