1983 FJ60 vacuum hose help (2 Viewers)

[arcadian]

Can anyone help me identify where the hoses that connect to the two pipes straight down under the radiator hose connect to?

 

[OSS]

If you look around you'll probably see two orphaned vacuum pipes nearby longing to be re-connected. Check the BVSV temperature sensors on the lower thermostat housing

 

[fjc-man]

It looks like the upper BVSV is broken off.

 

[arcadian]

After looking it is apparent the upper BVSV is broken, looks like I will be getting a replacement part and get those vac lines back hooked up.

 

[OSS]

Plug the open vacuum hoses

 

[g-man]

Some info on the BVSV...bimetallic vacuum switching valve. It is a solid plug. No fluid or air will come out of the nipples. When it gets hot enough to open the vacuum will pass from one nipple to the other. The top one is violet ..(on a 60) other colors for 40 series. Colors fade and change with age so if yours looks pink it probably started off violet. Different colored BVSVs open at different temps.

The upper BVSV works with the VTV..(vaccuum transmitting valve) pictured in image...(make sure the brown is facing the dizzy), to delay vacuum advance for a given time reducing NOx and HC emmissions

Why is this important? Well if you are completely desmogged, and maybe a PO has run the main vaccuum advance line directly over to the carb...then no need to connect the BVSV or buy another. Simply bypass it...and the leave the broken one in your thermostat housing.

 

[g-man]

The lower BVSV works with the Air injection system (air pump) to reburn exhaust gases. If you have no air pump, air injection rail or abv...you don't need this. Also it works with the cat and the air injection computer...if any of these are not working ...like the temp sensor on the cat....then you don't need it.

My engine is partially desmogged...(no air pump, no air rail, disconnect abv) and I have disconnected from the lower bvsv.

 

[2mbb]

The lower BVSV works with the Air injection system (air pump) to reburn exhaust gases. If you have no air pump, air injection rail or abv...you don't need this. Also it works with the cat and the air injection computer...if any of these are not working ...like the temp sensor on the cat....then you don't need it.

My engine is partially desmogged...(no air pump, no air rail, disconnect abv) and I have disconnected from the lower bvsv.

View attachment 2780741

Actually the lower (pink) BVSV is part of the choke opener system. When the engine is hot the choke plate is automatically pulled open to prevent an overly rich fuel to air ratio.

 

[g-man]

Actually the lower (pink) BVSV is part of the choke opener system. When the engine is hot the choke plate is automatically pulled open to prevent an overly rich fuel to air ratio.

Ok...but is this in addition to working with the AI system?

this image shows the lower working with the AI...

 

[UZJ100LC]

I was going to learn to wrench on an fj60 in disrepair I just picked up. After looking at this I am having second thoughts lol.

 

[OSS]

The vacuum hose routing diagram is infamously intimidating. But don't let it discourage you. Just get a copy of the emissions manual and each system is clearly illustrated and explained. See attached.

 

[fjc-man]

Ok...but is this in addition to working with the AI system?

this image shows the lower working with the AI...

View attachment 2780845

Looks like they share the vacuum source side of the BVSV, not the controlled side of the BVSV.