Hilux 4x4 Forum

F_D requested a photo of the vacuum layout sticker on the inside of the bonnet. Unfortunately it is virtually impossible to get a decent photo with the bonnet still attached and so I decided to redraw it and post it for all to have.

This vacuum layout should clear up any further issues around where the pipes go. I have checked my vacuum hoses against it and it is correct.

(F_D, I saved it as a pdf and it fits a A4 page so you may want to scale it down. Let me know if you need help or want anything changed)

Have fun

EDIT by F_D: I have added a smaller version of Scooter's sketch, click on the PDF file for a full-size version.

Hi Scooter,

Thanks a million, this has cleared up a lot of confusion, sadly the installation of the Nikki carb on my Toy is now clearly incomplete. Interesting, I don't have to following components:

- ACV
- VAC S/W Valve
- HAC

And my dizi vacuum has got 1 connection. Maybe in my circumstances EFI would be a good thing!

Bretton

Bretton, I think that you are twisting your own arm here
EFI would be a good choice for both economy and of course power. It just cost alot more :!:

I would start by overhauling the carb and perhaps seeing if the parts you say are missing are just in hiding.
It is the cheaper option and if it doesn't work then the loss is of no consequence when weighed up against the cost of the EFI.

Yes, true. We have 2 hiluxs in our weekend 4x4 group, mine and an EFI'd one, our engines are just about the same, both with BroSpeed like conversions and his one seems alot more responsive and has more power. So I am somewhat sold on the idea, but the wife is saying it's a bit expensive, hence why I would like to do it myself. I will still overhaul the carb this weekend.

Does your lux have aircon? If so, this may explain the extra vacuum pipes, I vaguely remember the mechanic saying something to this effect, when they fitted the carb.

Bretton

Yip, EFI is far more responsive as the fuel is pumped into the chamber immediately, it doesn't get lost while travelling through the inlet manifold.
That is also why it is more economical.

My lux has aircon yes. I will check over the weekend when I have some time and see if I can find out what works what.

Scott,

That's great, thanks a heap! The vacuum hose routing is always a bit of a mystery subject, with all the engine and other changes we love making. I will print out and post a copy on my car's bonnet when I get it back.


-F_D

Howzit F-D

I still have the 4Y sticker on the inside of my bonnet, do you want it? I can always try to remove carefully...

7MGTE wrote:Howzit F-D

I still have the 4Y sticker on the inside of my bonnet, do you want it? I can always try to remove carefully...

I would like it... but I don't know if it's "removable"...


-F_D

I'll be very careful... now where is my chisel and hammer.... probably next to the petrol and matches.... wonder if acid will work.... argh stuff it, that sucker will come off. I'll use the angle grinder!!

Ewald goeie sin vir humor

I was thinking of simply swapping bonnets... gonna spray mine anyway! But why stop there - we could also swap engines, and radiators, and...and... oh heck, why don't we just swap vehicles, will be much easier than trying to remove the sticker...


-F_D

No problem F_D, only a pleasure to help out.

Besides, now I can say I had a hand in the restoration of your vehicle.

Posted here a while ago.


viewtopic.php?f=3&t=580&p=3874&hilit=vacuum#p3874

Thanks Andrew, I will redraw that one too so the guys can print it out like the other one.
I see this one has the two blanked off vacuum pipes. Does you van have an AC? Electronic ignition or Breaker?
Just trying to figure out why they are different.

I have an aircon, and contact breaker ignition.

These diagrams are not very clear :?

Some rocket scientist cut out my high altitude compensator and tubes etc when I was living in Zambia. The vehicle performed better after that , I don't know why, it used to pink a lot before that....now nothing.

Hi guys, I have overhauled my Nikki carb, now the trick is to fit it. I found a part in the box which I can't identify, see pic, plus I found another gadget dangling next to the firewall with the hoses hacked off. Is this part of the vaccum system?


The vaccum pipe coming out of the top section of the carb has a thing called jet. I don't seem to have it.
Any assistance is very welcome.
Ron.

Sorry about the size of the pics, I either get them to big or too small
Ron.

Morning Ron

The first of your pictures is the altitude compensator IIRC. Are you battling to connect it?
The next pic, I cant help with. I have no idea what it is but it doesnt seem to be part of the vaccum system as it has electric running to it and the pipe had a hose clamp on it, usually consistent with fuel or water.

The part labelled "JET" in my diagram is in fact a valve and not a jet. It is a small yellow and white valve that sits between the choke and the base of the carb and works as a vacuum valve. See pic.

What part did yopu find in the box which you can't identify?

Thanks Scooter, The diagram on my bonnet is exactly as the photo submitted previously.I found the "jet". The overhaul manual calls it a restrictor.The altitude compensator dosen't appear in my overhaul manual. Is it really necessary on a coastal vechicle? Anyway were does it go.I might as well fit it in case I go to the reef one day.(it is the part I found in the box)
Thanks a lot for your help
Cheers,
Ron.

Ron, I have not found anything in writing that explains the valve you found nor can I say what it does or if it is necessary.

What I can say is that if your lux has been running without it, then leave it that way.
Otherwise, I can take some fotos this weekend for you and make a diagram of what to connect where.
It usually sits on the left front fender, close to the other funny thing you found there. It than has various vacuum pipes connecting to various places. I will check and let you know.

Hi Scooter, I found a clip on the left fender. Is this where the altitude compensater sits? If so where does it connect to.
Ron.

Ron, have you been able to connect it correctly? I use correctly in a loose sense as who knows whether their lux is connected correctly.

The position and clip you found is for the HAC and the vacuum pipes connect to various positions.
If you look at the diagram it is there but not entirely clear.

I had a look at mine this morning and this is what I found:
- The HAC has 4 outlet/inlets
- The top one is blocked off
- If standing at the laft fender (facing the engine) and looking down on the HAC, the two outlet/inlets go:
- The left one goes to the dizzy
- The right goes to the carb, closest side to you. Close to the top left.
- The last one at the bottom goes to the carb as well. This one connects on the other side of the carb, top right

Hope that helps a bit.

Hi Scooter, I've figured out the altitude compensation system. My dissy has only one connection but my electronic one which is with Motolek for checking has two.
The rest of the system is driving me dilly. Someone had a real go at it.
Sorry to be a pain in the butt, but could you identify the photo part is it the Gas F item shown on the schematic
It has three connections one blocked off. It sits on the top of the block. The second one goes into the block right front at the top of the block.

Hey Ron, glad its getting sorted. 'We' are here to help as much as 'we' can and it's only a pleasure. :D

The unit in the first photo is the BVSV valve (I have no clue what it does)
The unit in the second photo is in fact the GAS F valve (also no idea) and as you can see from the scematic it shouldn't have one blocked off unless yours has been changed.

I will need to check my system again to make sure i have everything as well. The schematic was the one taken from the bonnet and redrawn by me to help the ouens that dont have them anymore and I never bothered to check my system was correct.

That thingie in the second photo was just left blanked out in Bulldog when he still had a heart of Carburettor. Probably something not really required in our climate.


-F_D

Hi Scooter, I finished the job this afternoon, and the engine is running like a dream.I went for a test drive and lo and behold, no flat spot. Thanks again for all the help. I am going to fit a vaccum gauge, and get started on the "water" conversion.
Ron.

Congrats Ron, glad it is sorted now and driving without a flat spot is even better. :D

Eric, I have heard that the altitude compensator isn't necessary but it doesn't do any harm that I can tell and perhaps when taking the lux up Sani or the like it would help out. I haven't tried it with or without. I also reckon that in stead of trying to figure out which of the pipes to block off it's just better to have them connected.

I spoke to someone that told me if you disconnect the altitude compensation valve and blank off the pipes the air jets will then not get any air and your mixture would bee too rich. It is better to keep those things stock if you do not understand what they do and how to effectively remove them out of the system without compromising the complete working of your carb.

Hmmmm, this(the absence of the altitude comp unit) may explain my low RPM flat?? No worries soon I will be running EFI!

Bretton

I agree Bennie now if I could just find someone here in P.E. who really knows how these things all work as even the guys at Toyota seem baffled Its really causing me no endsof greef :!:

What's up Justin? Maybe we can help.

Guys... I've got a 22R and as far as I know the compensation valve is still connected as original. I can take some photo's if you like but like I said.. it's for the 22R.

Thanks Scott

The main problem is getting the carb sorted out with all the linkages and stuff someone in the past has mucked about with it and it is proving inposible to get sorted out :!:

If you post some pics in a new thread, I'm sure we can help.
Did my article on the carb overhauling not help at all?

Hi Scott

Overhauling the carb is not a problem that I can do its the external linkages and the vacume pipes someone mucked around with both they also removed the little 3 way valve on the head between the carb and tappet cover and also the altitude comp has been disconected at presant I only have one vacume pipe running to my dizzy for a temp measure if I could just figure on were to conect the to vacume canisters on the dizzy to carb for a tempory measure I will be halfway there the next think is to sort out the electronic choke as all the little cams are all mixed up on the linkage

Justin, what I meant was, could the photos I took not help you at all, for the linkages?

Not lekker when someone has played around with it and screwed things up. I wish I could help you out by being there.
My only suggestion is to find all the missing gadgets and switches and use the diagram to re-route all the vacuum pipes.

If you need any pics or anything let me know. I know it must be frustrating.

it would seem as if thats one of the most commen problems experience, Vacuume hoses theres always someone who goes around and makes a complete mess out of things with theese hoses.. glad to see that you got it sorted out ron. as for me, ill just have to go sit and figure it all out this evening and hopefully get it all sorted out.

just a pitty that the sticker on the bonnet wount be much of an assistance sine i recently got a elec dizzy installed with a "double advance"? (not to sure if its the correct term). At the moment it looks like ther is hope to get rid of that "lovely ping and flat spot"

Etienne, if you are getting pinging, then your ign. timing is too advanced, a stock std 4Y should be set at 4 to 6 deg... and a brospeed converted engine, seems happiest at 7-8deg... these figures are at the coast... IIRC with second diaphragm on the electronic dizzi had something to do with the aircon...

B

thanks Bretton
il have a look at it later and try 4-6 deg , but so far if i removed the timing from 8deg i pickup a flat spot. my concern is that the vacuum hoses have been looped at verious points and one of those chineese carbs have been put on. thats the reason im taking a look at the vacuum hoses to see if that could be the cuase of the timing advancing to much. time to put my lux on the operating table.

i will post some pictures under a new tread then we can have a look and see whats going on. thanks for the advice

gOOD DAY, Could any one help me with how to tune up my 4Y carburetor for good fuel consumption?

Mine is currently running at 6.4km/l and I wish I could get it at atleast 9-10km/l

Any one please?

Good morning
Some assistance required please.
The vacuum hoses were changed by the previous guy who serviced the carb and the vehicle ran better. I now overhauled the carb and brought the hoses back to the way it was intended to be from the factory. There is a vacuum hose diagram in the post right at the top for reference.
From the HAC valve bottom centre the hose runs into a “T” piece. From there one end goes to distributor and the other to a check valve and then to the inlet (GAS F).
One thing confuses me is that the “T” piece bottom seems to be a restrictor, that is less air passes through the bottom than the two top sides. Is that how it is supposed to be?
If so which hose does the restrictor side connect to?
As per the diagram above the restrictor side goes to the HAC valve. If I connect it like that, the “T” piece sits odd and, one side of the vacuum hose faces up ward, above the engine. Unfortunately I cannot upload pictures.
Advice, and pictures if possible would be appreciated.