1972 fj40 vacuum routing

[Tigger72]

Trouble tunning and ticking off items. Right now im going to bypass the evaporative control vacuum switch which i assume has failed (or somewhere in that system). What don connect to what for the system to work correctly? Here is my guess:

Base of carb to dizzy (for vacuum advance which is my next check)
Charcoal canister to airbox
Plug intake ripple
Ignore chokes diaphragm

How is my guess? Did I need to do anything different?

Thank you!

 

[65swb45]

If the port on the base of your carburetor that you are referring to is on the outboard side, facing the driver’s fender, that is a constant vacuum port, not appropriate for use on the distributor.

And yes, plumbing the vent from the charcoal canister into the lid of the air cleaner is appropriate.

 

[Tigger72]

If the port on the base of your carburetor that you are referring to is on the outboard side, facing the driver’s fender, that is a constant vacuum port, not appropriate for use on the distributor.

And yes, plumbing the vent from the charcoal canister into the lid of the air cleaner is appropriate.

Thanks! That is the port i connected to the diaphragm on the distributor. What is the appropriate plumbing? Should the distributor be attached to the intake port? Or in this scenario is the vacuum advance eliminated?

 

[Tigger72]

Thoughts.

Thanks! That is the port i connected to the diaphragm on the distributor. What is the appropriate plumbing? Should the distributor be attached to the intake port? Or in this scenario is the vacuum advance eliminated?

Here is a reference to what I am trying to diagnose.....

 

[65swb45]

Thanks! That is the port i connected to the diaphragm on the distributor. What is the appropriate plumbing? Should the distributor be attached to the intake port? Or in this scenario is the vacuum advance eliminated?

You need to positively identify which distributor you have to answer that question. If you can’t post a pic, do a search for one and see which matches.

 

[Tigger72]

You need to positively identify which distributor you have to answer that question. If you can’t post a pic, do a search for one and see which matches.

 

[Tigger72]

It's the original. The rig itself is a May of 1972

 

[65swb45]

Yeah, don’t worry about putting vacuum to that. Vacuum retard.

 

[Tigger72]

Interesting. The FSM labels it as vacuum advance. Why vacuum retard? Is it mechanical advance then? If thats the case, then no vacuum hoses are needed for normal operation and i can just plug everything?

 

[Pighead]

Interesting. The FSM labels it as vacuum advance. Why vacuum retard? Is it mechanical advance then? If thats the case, then no vacuum hoses are needed for normal operation and i can just plug everything?

Vacuum retard might have been an early response to smog laws?
It is still a mechanical advance.
Plug everything

 

[Tigger72]

Thanks guys. Another quick question. Is the BB on this 1972 flywheel TDC? Or is it 7 BTDC? I'm seeing mixed responses in other threads.

 

[Pighead]

Thanks guys. Another quick question. Is the BB on this 1972 flywheel TDC? Or is it 7 BTDC? I'm seeing mixed responses in other threads.

The BB is 7*BTDC

 

[ToyotaMatt]

Trouble tunning and ticking off items. Right now im going to bypass the evaporative control vacuum switch which i assume has failed (or somewhere in that system). What don connect to what for the system to work correctly? Here is my guess:

Base of carb to dizzy (for vacuum advance which is my next check)
Charcoal canister to airbox
Plug intake ripple
Ignore chokes diaphragm

How is my guess? Did I need to do anything different?

Thank you!

do you have in-hand a actual 1972 paper print media Land Cruiser F1.5 Emissions Manual , this is a dedicated FSM that coverss each sub-system in a chapter by chapter format , as well as all the topics , things and general questions you have discussed here thus far , including detailed Tune Up spec's and procedures ...

more in-dept then the grey 1972 F Engine FSM paper print media manual ...

i am not discussing a PDF version on a cell phone from a link on google here , so please do not relate or confuse the two topics ...


if you do not , and would like specific topics here posted , i have all the above original's here at the Laboratory's library and can help with this via photos below ...

matt ...

,

 

[ToyotaMatt]

Your BB / 7’ Degrees BTC before top dead center is a Stainless Steel Ball Bearing the same size spec. as your Red Ryder single level action / single cock spring loaded teenage mischief maker …

Polish it off all grease and oil etc , get a nice oil base paint pen the metal kind with the BB inside it when you shake it prior to pushing the tip to soak it

Get a Fluorescent Blue or Orange one too ..

Use the white on on the BB it will reflect the timing lights strobe-pulses of Lumen Spectrums the best for you

The orange / blue paint pen yoh will use on the actual TDC mark , its a Vertical hatch mark or thin groove on the flywheel too

Strike the entire groove well


Use the 2 thin Coats of each color each location this gives you the best results ..


Now you have 7’ BTDC marked clearly and TDC too and there totally distinguishable
From one another ….

Make sense ?

This is how I approach any manually adjustable toyota timing needs and it’s a flawless way long term too

You clean. Each location with brake clean well the color keyed paint dots are a lifetime
Forever goodness goodie to rely on …

I also recommend keeping your Vacuum actuator correctly hooked up using the total system routing digram below ..

This is Not about the keeping it all original and or making less fossil fuel global warming topics …

This is my opinion that it will run better verses being simply plugged based of my own experience …

Sure , other Emissions components are not needed and or can be capped off / deleted …

You will have to by-pass the Vacuum
Switching valve box on the drivers fender of course taking the hose directly from the actuator on the dizzy to the port on the carburetor..,

Just study the rounting diagram and note there are 2 carb vacuum ports ..fyi

Try it both ways correctly hooked up as you see below and also the port on the dizzy capped off , drive around a few days each way and report bank how this felt and your overall experience / driving and acceleration through the gears …

This would be a good thing for others to read and learn from too …


Hope this helps ….

Matt .


.

 

[ToyotaMatt]

 

[Tigger72]

do you have in-hand a actual 1972 paper print media Land Cruiser F1.5 Emissions Manual , this is a dedicated FSM that coverss each sub-system in a chapter by chapter format , as well as all the topics , things and general questions you have discussed here thus far , including detailed Tune Up spec's and procedures ...

more in-dept then the grey 1972 F Engine FSM paper print media manual ...

i am not discussing a PDF version on a cell phone from a link on google here , so please do not relate or confuse the two topics ...


if you do not , and would like specific topics here posted , i have all the above original's here at the Laboratory's library and can help with this via photos below ...

matt ...

,

I do not. I have the original 2 grey FSMs and the glove compartment owners manual, but that's all for manuals. My father purchased it, so I have everything he still had down to the original loan paperwork, but nothing specific to the evaporative emissions control system. I have everything capped off at this point as I don't have emissions checks where I live, but a photo would be helpful. Thank you.

 

[ToyotaMatt]

I do not. I have the original 2 grey FSMs and the glove compartment owners manual, but that's all for manuals. My father purchased it, so I have everything he still had down to the original loan paperwork, but nothing specific to the evaporative emissions control system. I have everything capped off at this point as I don't have emissions checks where I live, but a photo would be helpful. Thank you.

See above ,

If you need any Addional pages feel free to ask


The 1972 red cover binder emissions F1.5 FSM is a must have , not to make you install
And have all smog parts present , accounted for and working like new …

It’s essential in my world because it outlines klearly what all was there originally , so you can hook up the needed still now in 2025 basic need plumbing like the PCV valve and valve cover breather stystems that every single 1972 F1.5 Engine on the Globe has & Needs , FJ40 FJ45 FJ55 FA100 etc …

 

[Tigger72]

Thank you! So sorry, I missed the photos and connected responce! I will take a look.

 

[Tigger72]

Also, I greatly appreciate the time taken for your responce! Thank you!

 

[65swb45]

See above ,

If you need any Addional pages feel free to ask


The 1972 red cover binder emissions F1.5 FSM is a must have , not to make you install
And have all smog parts present , accounted for and working like new …

It’s essential in my world because it outlines klearly what all was there originally , so you can hook up the needed still now in 2025 basic need plumbing like the PCV valve and valve cover breather stystems that every single 1972 F1.5 Engine on the Globe has & Needs , FJ40 FJ45 FJ55 FA100 etc …

Your reply proceeds on the assumption that the 50+ year old vacuum switching valve and emissions computer are still working properly. Neither of these are safe or reasonable assumptions.

But I would agree that a short drive under both conditions for a seat of the pants evaluation would be appropriate for any consumer wanting to gather additional information for themselves, rahter than just relying on suggestions from an internet forum