13B-T owners/gurus: where do these vacuum lines go?

[toyobaru]

I noticed these two lines don't connect to anything... any input or link to a diagram would be great!


vacuum line by dtpaladino, on Flickr

 

[Hulsty]

There are many vacuum lines on a 13BT, I suggest you get a copy of the workshop manual. The ones under the manifold go to the vacuum solenoids near the battery tray I belive or the ones in the quarter panel, no idea what they actually do.

 

[toyobaru]

I have the FSM, and the best diagram I can find is on EM-45, and it still doesn't give enough info. The vacuum system has been fiddled with by the PO, I'd like to get it back to spec. I'd really appreciate if someone could take some pictures for me!

Thanks!

 

[kbushnz]

Does this help ???
http://www.toyodiy.com/parts/p_G_1987_TOYOTA_LAND+CRUISER_BJ74RV-MNXQ_1708.2.html

 

[Malahki]

Does this help ???
http://www.toyodiy.com/parts/p_G_1987_TOYOTA_LAND+CRUISER_BJ74RV-MNXQ_1708.2.html

The diagram will be blocked from us North Americans

 

[shamusFJ73]

From what I can tell A goes to the engine shutdown butterfly and B goes to the the shutdown vsv, hope this helps

 

[John Galt]

This will help:
https://forum.ih8mud.com/diesel-tec...2899-13bt-vacuum-system-diagram-shut-off.html

 

[toyobaru]

Thanks for the diagram. From what I can tell, my VSV is plumbed completely differently. I can definitely tell its been messed with. I will post pictures in a bit.

 

[toyobaru]

VCV by dtpaladino, on Flickr

Hard to tell from the image, but the valve is plumbed directly to the VCV and the two other vac lines to the vcv are plumbed behind and under.

So why the disconnected hoses? Is that length of vacuum hose just bypassed? My vcv is working, although the wiring looks awful.

 

[John Galt]

Here's a pic of the stock set-up.


https://forum.ih8mud.com/attachment.php?attachmentid=136903&stc=1&d=1176985149



https://forum.ih8mud.com/attachment.php?attachmentid=487297&stc=1&d=1295895907

Vacuum from the pump is applied to the 'back' of the VSV.
When the VSV is energized the valve switches the vacuum to the air-shutter pot on the crossover, opening the shutter so the engine gets air. When the VSV is de-energized, the air shutter closes, and vacuum is switched to the [STRIKE]terminal filters [PNC83381A] located in the fenderwell[/STRIKE] the air intake.

The VSV is normally mounted on the engine block as shown at #7 in the pic. This is an unreliable location that gets a lot of heat, vibration and often water-spray. On my truck, when the original VSV failed, I mounted the new one at a higher location on the firewall by extending the #8 hose which connects to the vacuum pipe behind the engine.


The VSV on your engine has been relocated too, with a direct connection to the air shutter bypassing the disconnected lines.

An easy way to disable this engine for security is to switch the two vac-hose connections to the 'front' VSV ports.

 

[shamusFJ73]

I dont know why everyone keeps saying the objects near the batteries are filters, if they were you would have no vacuum.

They are in fact your boost sensors to control the lights on the dash, one is for boost and the other over boost. They are fed from the crossover pipe

 

[toyobaru]

Here's a pic of the stock set-up.

The VSV on your engine has been relocated too, with a direct connection to the air shutter bypassing the disconnected lines.

Thanks for the image John! I figured they had been bypassed.

 

[John Galt]

...
They are ... boost sensors to control the lights on the dash, one is for boost and the other over boost. They are fed from the crossover pipe

thanks for the correction.

On the VSV one tube is vac, one tube goes to the air shutter, where does the other tube from the VSV go?

 

[shamusFJ73]

The other tube runs into the intake just after the airbox

 

[toyobaru]

My VSV problem just returned. I've checked the continuity in the VSV, comes back normal, except I noticed I have a 12V VSV, on a 24V truck.... is this normal?

The engine starts, runs rough for a few seconds and then stalls. When I manually hold open the shutter pot butterfly valve on the intake, it still will not run. Is my problem separate from the VSV?

 

[toyobaru]

From this thread: https://forum.ih8mud.com/70-series-tech/376880-vacuum-shut-off-valve.html :

Some thoughts to consider.
The vacuum pot closes the shut off valve by having vacuum applied to it from the VSV valve when you turn the key off, the normal VSV is no power, vacuum passing thru to the pot. If the key is off and the motor dies the VSV is working (at least in this mode).
The rig has been off (no vacuum being generated) the vacuum pot and VSV has no source of vacuum except stored vacuum, when you turn the key it should shift the VSV to vent the vacuum stored in the pot and lines from the pot to the VSV, the vent allows the pot to open the shutter which allows the engine to run, either the VSV is not shifting or the vent is plugged. If the vent is plugged it will not allow the shutter to open, when you pull the hose off the pot you are making a vent.
The vent (since I don't know what rig you have) could have a filter (very small) pushed on the end of a nipple on the VSV or a rubber tube over to the intake hose between the air filter and the turbo (if you have one) or the intake tube.
If the VSV filter is plugged or the vent hose is pinched or plugged it will not allow your motor to run.
The VSV could also not be shifting. the power supply could not be making it to the VSV (the VSV shifts to run with power) if you have a broken wire or a bad ground the VSV will not shift to the run position (venting the pot).
I hope this helps.
Jim

I looked for a filter, but could find nothing. I'm starting to think my problem goes beyond VSV, because with the vac line disconnected to the shutterpot on the intake, it still wont run...

I guess I will pull apart the intake and check for obstructions. Whats the best way to check for an air leak in the fuel lines?

 

[John Galt]

I have a 12V VSV, on a 24V truck.... is this normal?

no, and it's likely poached unless it's been wired with 12v.

Use either a 24v VSV like TOYOTA Valve 90910-12020

or a 12v VSV with 24/12 convertor.

The engine starts, runs rough for a few seconds and then stalls. When I manually hold open the shutter pot butterfly valve on the intake, it still will not run. Is my problem separate from the VSV?

appears to be two problems:
obstruction or air in the fuel lines and
defective VSV

Have you serviced the fuel sedimenter?

Can you push fuel through the system with the hand primer pump on the fuel feed pump?

 

[toyobaru]

Thanks John. I'll have to keep an eye out for a 24V VSV.

I determined that I'm getting some big air bubbles in the fuel. I tried pumping the hand primer until I saw a steady stream of fuel, hooked everything up, and it idled for about 5 minutes before sputtering and dieing again. So, I tried the hand primer pump again, and found another big air bubble. Pumped it until fuel started flowing, started it, and it ran for about 3 minutes before sputtering.

So, I spose I have a leak somewhere in the fuel system... time to do some more reading. Any tips or tricks for investigating a leak?