How many different vacuum ports on Aisan (3)F carburetor? (1 Viewer)

[Cruisunder]

The FSM is not very specific about the vacuum ports on our carburetors:

All three hoses called (b) are connected to ported vacuum as they are above the throttle plate. Are all three leading to the same location in the throat, or are they functionaly different? I’m asking as I want to make sure my dizzy vacuum advance is connected to the right port (no. 2 from the right out of a total of 4 ports at the base of the carb, in my case). This question follows from a previous thread:
Carbed 3F decel / emission control computer testing (re. after-fire) - https://forum.ih8mud.com/threads/carbed-3f-decel-emission-control-computer-testing-re-after-fire.1281004/
but I put in a new post coz I figured more people might be interested in the answer to this question.

 

[ToyotaMatt]

​

i have a original paper print media 3F FSM , how can i help ?

 

[Cruisunder]

​

i have a original paper print media 3F FSM , how can i help ?

View attachment 2981039​

Does that have a diagram, or instruction explaining which vacuum port is which?

 

[ToyotaMatt]

Does that have a diagram, or instruction explaining which vacuum port is which?

i will see

what destination market carb we taliking here ?

my FSM OEM is a global spec. edition , so it covers ALL 3F carbs globally

japan

EU
saudi

more too

etc >

?

thanks
matt

 

[Cruisunder]

i will see

what destination market carb we taliking here ?

my FSM OEM is a global spec. edition , so it covers ALL 3F carbs globally

japan

EU
saudi

more too

etc >

?

thanks
matt

Australia plz. Thanx

 

[ToyotaMatt]

Australia plz. Thanx

copy that

AU coming up

 

[ToyotaMatt]

curious why u need to know all this tech ?


- do u not have any carb. now at all ?

- your current AU carb should have all the correct ports right ?

-it would help me help u if i understood the whys and the back ground

- note ALL AU foot notes on each page i post here :

- NOTE some foot notes and images are for a NON-AU only applications too

- the AU had tighter emissions standards then general countries this much i know


- do u have a TP or Choke breaker , TP is a throttle positioner i am 98% sure correct reference ?

- my summery is after a bit of careful study , the entire fuel section the AU ports hose layout and routing is 100% clearly shown in detail and talked about in the foot notes here ?


hope this helps mate ?

kindly matt

 

[Cruisunder]

Thanks @ToyotaMatt , appreciate your deep dive into the FSM. I have a pdf copy of same 1984 3F manual. See how each image describes 3 of the hoses as (b) “other three vacuum hoses”? I’d like to know if the ports at the base of the carburetor are connected via a common, or are they tapping into different locations and therefore send different vacuum signals.

The reason is I want to check that in sending the right ported vacuum signal to my distributor. The FSM also states that there should be about 10.6” of ported vacuum at 1,000 rpms, resulting in 9.6 deg of vacuum advance (and there are other values as part of this vacuum advance curve as well).

I have been testing the advance curves on my 3F carb / dizzy combination and am so far getting a definite vacuum advance, but it seems to kick in later, and by not as much. So my quest is to make sure I’m not tapping into an incorrect port on the carburetor.

I’m planning to test and compare vacuum values from these different ports as well - data will tell.

 

[ToyotaMatt]

did u see the 3F image last of the real engine ?

see how hoses are routed there ?


you only have 3 ports right ?

please clarify this key point please ?

thanks

 

[ToyotaMatt]

do u know what your frame # and modle ID codes are on your engine bay data ID plate tag ?

pleasse supply me them both

if unsure a close up of your engine bay Aluminium tag on fire wall

u can PM me this info of course too



i can use this to apply to my actual microfiche slides i have

it has vacuum diagrams in it


this may be your answers ?

i have found this RODEO 411 this way before many times


thanks matt

 

[OSS]

The drawing in the manual clearly shows how the hoses are supposed to be connected.
I say / just connect them as shown and forget about it. It’ll be connected correctly.

Toyota manuals never explain everything - only information that’s needed. Obviously they didn’t think labeling the vacuum ports in the manual was important since the drawing shows how the hoses should be routed.

 

[Cruisunder]

The drawing in the manual clearly shows how the hoses are supposed to be connected.
I say / just connect them as shown and forget about it. It’ll be connected correctly.

Toyota manuals never explain everything - only information that’s needed. Obviously they didn’t think labeling the vacuum ports in the manual was important since the drawing shows how the hoses should be routed.
View attachment 2981137

The drawing in the manual clearly shows how the hoses are supposed to be connected.
I say / just connect them as shown and forget about it. It’ll be connected correctly.

Toyota manuals never explain everything - only information that’s needed. Obviously they didn’t think labeling the vacuum ports in the manual was important since the drawing shows how the hoses should be routed.
View attachment 2981137

Mmm, yes the diagram almost shows where they go but not 100%. Here’s my spaghetti:

So port 4 sits between 1 & 2 and doesn’t show in the diagram. It all looks to be hooked up as it should but I’m still virtuous, are all ports seeing the same or a different vacuum. If they’re different then i want to be 100% certain they are hooked up correctly.

 

[OSS]

Ok. To verify when those carb pipes pull vacuum, a vacuum gauge could be teed into one, then the engine run at different RPMs & load while looking at the vacuum gauge.
Then hook up the gauge to the next pipe and do the exact same experiment.

If the gauge performs exactly the same on all the pipes, then the pipes function identically and hose location wouldn’t matter.

If vacuum behaves differently on different pipes — then the mystery remains.
Best if someone with a 3F carb could double check their setup.

 

[Cruisunder]

Just tested at a couple of rpms, no load:

Interesting … looks kinda logical and hose connections appear correct.

 

[ToyotaMatt]

Just tested at a couple of rpms, no load:

View attachment 2981726

Interesting … looks kinda logical and hose connections appear correct.

this is now easy with your live tech pics toyota in methodical and usually does NOT overlap and criss cross vacuum hoses ever .......

i concur u have it NOW correct in my opinion ..


most excellent my friend


now that your all buttoned up and looking solid routing , i would like to take a moment and change the tech subject for a minute , or in other MUD language :

HIJACK your tech thread ........

its ok the HIJACK will not last long and it even involves you and your SNAPPY 3F carb engine bay and extra MR. CLEAN engine bay too WOW im impressed !



so the HIJACK topic is :


can u please post some glamor shots of your CARB side ENGINE bay , and also a few glamor shots of your INTACT 3F valve cover decal sticker i can see poking its cute

little head up here in the above image


- i am working hard to Reproduce ALL the various 3F carb engine bay oem decals , correct placement and period correct fit form and function

- this is what i have so far and my limited references images i have managed to gather so far ?


- you and your 3F present a unique and rare opportunity to make Manifest tonight into reality tomorrow

- i will be happy to mail you out ALL my work thus far to the AU no problem .......

- thanks for any assistance



matt

 

[Cruisunder]

this is now easy with your live tech pics toyota in methodical and usually does NOT overlap and criss cross vacuum hoses ever .......

i concur u have it NOW correct in my opinion ..


most excellent my friend


now that your all buttoned up and looking solid routing , i would like to take a moment and change the tech subject for a minute , or in other MUD language :

HIJACK your tech thread ........

its ok the HIJACK will not last long and it even involves you and your SNAPPY 3F carb engine bay and extra MR. CLEAN engine bay too WOW im impressed !



so the HIJACK topic is :


can u please post some glamor shots of your CARB side ENGINE bay , and also a few glamor shots of your INTACT 3F valve cover decal sticker i can see poking its cute

little head up here in the above image


- i am working hard to Reproduce ALL the various 3F carb engine bay oem decals , correct placement and period correct fit form and function

- this is what i have so far and my limited references images i have managed to gather so far ?


- you and your 3F present a unique and rare opportunity to make Manifest tonight into reality tomorrow

- i will be happy to mail you out ALL my work thus far to the AU no problem .......

- thanks for any assistance



matt




View attachment 2981749



View attachment 2981750View attachment 2981751View attachment 2981752



View attachment 2981753




View attachment 2981754




View attachment 2981755

Sure man, here’s my best angles

 

[ToyotaMatt]

Sure man, here’s my best angles

View attachment 2981795

View attachment 2981797

u think u can pull your carb off for a few minutes so we can see the UNICORN in full view ?

 

[ToyotaMatt]

ok

here are some tech images for future reference ;

 

[Cruisunder]

Thanks for these photos. Do the links work for anyone, they come up as requested page cannot be found, for me.

Are you sure these photos are of a 21100-61251 carb, as mine does not have a throttle positioner?

 

[ToyotaMatt]

Thanks for these photos. Do the links work for anyone, they come up as requested page cannot be found, for me.

Are you sure these photos are of a 21100-61251 carb, as mine does not have a throttle positioner?

19100-61160 is next


technical T-TEN Advanced Logistics LEVEL Teq progress takes time .............

​