3L-T Vacuum routing (1 Viewer)

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Nov 23, 2017
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Prince Rupert BC
Hey boys. new to the forum, looking for some knowledge i heard this is the place to go. I've recently rebuilt my 3L turbo and figured while the engine was out id toss the fuel compensator off an old 2LT Pump. The swap went fine, but im having troubles with the Vacuum routing. The diagrams online show lots of sensors and what not but this engine has only none of them. As she sits there is 2 nipples on pump, 1 on the intake manifold, and 1 on the turbo side of the engine going through a sensor coming from the vacuum pump. Any info would help alot. Thanks in advance!

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In your last two pictures:

The one on the intake manifold connects to the one on the top of your boost compensator.

I *think* the one under your boost compensator is just a vent. Hopefully someone with more experience on that chimes in.

In your first picture:

The thing mounted on your A/C compressor is a VSV (Vacuum switching valve). The electrical part switches the valve and turns vacuum on or off. One part of that VSV probably goes to your vacuum pump. Follow the other vacuum line and let us know where it goes. Maybe it has something to do with A/C idle up?

Thanks for those pictures. Worth a 1000 words as they say.

What vehicle is this by the way? Did it originally come with a 3L engine?
 
From a quad cab hilux 1991. From the VsV it runs down to a banjo on the back of the alternator, 2 nips on the banjo the other one runs to the vacuum pump which is mounted next to the brake booster (RHD)
 
@GTSSportCoupe I figured you'd be the guy who would know, I directed the OP here from a FB group, lol.
 
Your first picture there is the vacuum pump on the back of your alternator. Diesel's don't make engine vacuum because they generally don't have throttles, or they have turbos which make positive pressure. So manufacturers put vacuum pumps on them.

Thing in your second picture is a vacuum reservoir I believe.

I think basically if you leave the Vacuum pump, VSV, Vacuum Reservoir, Brake booster all as it was, you'll be just fine.

It's really just the boost compensator that you need to hook up I think.

Again, I'm more familiar with the 2LTE, so others may way in with more information here.

One thing you can do to see the factory drawings for your vehicle, is go to megazip.net. It'll show you all the part numbers and how things are from factory. Just select your chassis number (see the ID tag, or look at your frame) and year/engine etc.: Spare parts for Automobile Toyota HILUX | Buy spare parts for automobiles and moto equipment from Japan at reasonable prices in MegaZip online shop. (1914)
 
Only thing is the top line on the VSV runs to the pump side of engine, but not sure where it hooks too.

Sorry I thought that end was connected ok. I took a look at the Megazip site, and from what I can tell, it is supposed to connect to an idle up actuator. Here is the drawing. Your truck I think is an LN106, so the top part of this drawing would apply. You need to look for 88031 (the actuator) near/on your injection pump. I think this is the idle up for the A/C.

Might be that other vacuum connect under your boost compensator. I can't see well enough from your picture.

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It looks like the aircon fast idle actuator is missing.
 
Yes i pulled that actuator off when i did the pump. Can it be bypassed or is it needed?

If you use your A/C might be worth keeping. If not, just remove the VSV and vacuum line, and cap off the line at the vacuum pump.
 
Yes i pulled that actuator off when i did the pump. Can it be bypassed or is it needed?

It can bypassed but why would you want to if you use the aircon? I think you can adjust them if they are too fast/too slow.
 
I swapped all the linkages off the 2L-T pump to the 3L because it seemed to work better, will probbaly have to toss the 3L stuff back on?
 
Hey boys. new to the forum, looking for some knowledge i heard this is the place to go. I've recently rebuilt my 3L turbo and figured while the engine was out id toss the fuel compensator off an old 2LT Pump. The swap went fine, but im having troubles with the Vacuum routing. The diagrams online show lots of sensors and what not but this engine has only none of them. As she sits there is 2 nipples on pump, 1 on the intake manifold, and 1 on the turbo side of the engine going through a sensor coming from the vacuum pump. Any info would help alot. Thanks in advance!

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Hi All, This is my first EVER post, on any thing as far as I know. I need some help. Have purchased a fully rebuilt 12HT. Had the whole thing running for a few months OK, then the brakes turned to crap. Brake light on dash was coming on as well. Knowing little of what was to come I thought that the light was brake fluid level. The Alt and Vac pump was new and brought over from the old engine.
I was putting new shoes on the back as they were stuffed. Th brake light was still on, the brakes were still crap so I decided to investigate. Found the vac switch on the booster line and then to Vac pump. Anyway, I discovered the vac pump was dray as a dead dingo's d%^&er.
No oil in it > cracked the oil line on the block and started the engine. No oil came out. Oil pressure is all the way up so is OK. I took the banjo bolt off the block but could not determine if there was any opening to feed oil to the hole -> and vac pump.. I am wondering if anyone can give me some idea of what it should be. Maybe during the engine re-furb the hole was sealed off for some reason and not re-opened?
 
It really needed its own thread or added onto another 12HT thread. If someone in the future is searching for this topic, they wont find it in a 3L vacuum thread

Can you poke something in there to ascertain whether it is blocked off.
And does the vacuum pump suck its own oil up or does the engine oil pressure push it up to the pump?
 
It really needed its own thread or added onto another 12HT thread. If someone in the future is searching for this topic, they wont find it in a 3L vacuum thread

Can you poke something in there to ascertain whether it is blocked off.
And does the vacuum pump suck its own oil up or does the engine oil pressure push it up to the pump?

OK, I am new to this. I am not sure where to start threads etc, but thanks for your reply. A huge part of the problem is knowing weather it sucks it up or weather the oil pump pushes it through. There seems no absolute certainty about this but I am tending toward the pump pushing it through. I had a mirror and torch and to the best of what that offers it seemed like a blind end, but it would only need a small hole I would guess, and it might come from the side? All I am doing at present is tipping some oil in every few days. The brakes are really bad the ligth usually comes on at idle... Thanks for answering. I will try on the 12HT somewhere...
 
It really needed its own thread or added onto another 12HT thread. If someone in the future is searching for this topic, they wont find it in a 3L vacuum thread

Can you poke something in there to ascertain whether it is blocked off.
And does the vacuum pump suck its own oil up or does the engine oil pressure push it up to the pump?
the vacuum pump does not have its own oil lubricated with engine oil
 

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