Hilux 4x4 Forum

Posted: **Tue Apr 03, 2018 7:30 pm**

So the guys still driving the old Hiluxes with the old 22r and 4y motors will appreciate this mod the most.

A while back I found this website. eagle-research.com I am not affiliated in any way here, I was simply looking for a way to get better fuel economy, turns out I found the cheapest way to 8km/l for a 22r, an improvement from 5.5km/l Total cost R5.00.

Basically the idea is that you pressurize your float bowl so that the carburetor is balanced, it essentially enhances the emulsification of the fuel among other things without you changing anything. Installation is simple with all the requirements being some fuel hose, a vacuum source and a tap to decrease or increase vacuum, you attach on side of the hose to a vacuum source (in my case I installed it on one of the many vacuum ports I had available on the carb itself and attached the other to the vent tube on top of the float bowl with the tap in between. Too much vacuum kills the engine, to little wont work, once you've turned the tap till a little way before it dies you have it tuned. That's it.

If you guys have any questions or would like to even have a look at the book this guy sells on his website I would be willing to share.Good info like this is priceless.

Posted: **Wed Apr 04, 2018 6:52 am**

What are your actual results?

Posted: **Wed Apr 04, 2018 5:06 pm**

Does it actually work? I would love a copy of the book, thanks

Posted: **Wed Apr 04, 2018 9:16 pm**

Well since I installed this little mod I have seen an increase of 2.2km per litre over and above my current fuel economy, instead of 5.5 I am getting 8km/l. I have a gas flowed head with a branches and free-flow exhaust, I am not sure if these contribute to the engines fuel economy. Also the engine feels smoother and slightly more powerful.

And to be honest here my records are over 2 tanks of fuel driven between Gordons Bay and Paarl 60% town and 40% open road with 500kg of guys and gear in the back. I drive mid throttle not pushing more then 130km/h on the down hills.

DAX send me your email and I'll send you the PDF.

It really would be great to get a few guys experimenting with this, if we can help even a few guys get more km/l then that's awesome.

Posted: **Thu Apr 05, 2018 6:41 am**

I have a carbed 22r so would love to give it a go sometime - don't see how it can do much harm. Can I send you my address as well Pampoen?

Posted: **Thu Apr 05, 2018 9:52 am**

Please do Tim, just PM me your email.

Posted: **Fri Apr 06, 2018 10:50 am**

Luke, may I please have a copy?

Posted: **Fri Apr 06, 2018 11:30 am**

Guys of you want me to send you the PDF book, just pm me your email address.

Posted: **Fri Apr 06, 2018 3:05 pm**

Thanks for the copy Luke!
Would you mind posting a close-up pick of your setup when time permits? I'm interested to see which vacuum port you used - I'm thinking of the unused AC port as mine has no AC..

Posted: **Sun Apr 08, 2018 2:49 pm**

Sorry about the wait. Here are the pics.I used a fish tank air restrictor as the valve for the system.
https://ibb.co/eOLFZx
https://ibb.co/gh2Uux
https://ibb.co/ddUaZx

Posted: **Tue Apr 10, 2018 6:21 pm**

Guys just a little more info on tuning the carburetor enhancer, once you have all the stuff on the carb start the engine with the tap fully closed, slowly open it until the engine wants to die, back it off slightly until the engine runs smoothly again. Take the vehicle for a spirited drive around the neighborhood, especially one with lots of stop streets, if the engine dies after braking hard then close the tap slightly until it does not die. After that you should be good. Your carb enhancer should be doing saving you petrol.

Posted: **Wed May 02, 2018 11:07 am**

Any update on your consumption Luke? Still performing well? Have bought the components but haven't got round to it yet, alternator packed up the other day:/

Posted: **Wed May 02, 2018 1:25 pm**

Yes it seems to be giving me better fuel consumption. On a 65 litre tank I got 500km with 5 people in the car and 300kg of stuff in the back. That is IF...... and a big if, I drive nicely. So not a massive increase but still much better then the 5.5km/l I was getting.

Posted: **Fri Oct 26, 2018 2:59 pm**

Luke did you implement the small vent in the tube as shown above (3)?

I was playing around with it yesterday - the vent would theoretically be the same as a vacuum leak which isn't a great idea, and also adds more air after the carburetor causing the motor to run lean. Without the vent the motor revs up as you gradually open the valve, but it doesn't get to the point of stalling even with the valve fully opened. I even tested a straight through pipe. I have yet to test the setup with a vent but I would imagine it may be the cause of the running rough or stalling when the valve is opened too far.

Posted: **Fri Oct 26, 2018 10:45 pm**

As I see it, that's exactly what it does, allows more air in and leans out the mixture. The only reasons I can see for taking the extra air from the float chamber is that it takes in some fuel vapour as well as air and that the resulting negative pressure in the bowl retards fuel flow to the jets as the revs increase.

All of this serves to lean out the mixture, an adjustment that is not present on the Nikki carb (along with many other carbs of the same era). Here's the danger, run too lean and you burn valves over time.

I can't help feeling a little sceptical.

Posted: **Mon Oct 29, 2018 12:05 am**

Tim86 wrote: ↑Fri Oct 26, 2018 2:59 pm Luke did you implement the small vent in the tube as shown above (3)?

I was playing around with it yesterday - the vent would theoretically be the same as a vacuum leak which isn't a great idea, and also adds more air after the carburetor causing the motor to run lean. Without the vent the motor revs up as you gradually open the valve, but it doesn't get to the point of stalling even with the valve fully opened. I even tested a straight through pipe. I have yet to test the setup with a vent but I would imagine it may be the cause of the running rough or stalling when the valve is opened too far.

That's strange. I have yet to modify my Weber carb yet but I know on the Nikki I ran a vacuum hose from the float bowl vent to one of the vacuum ports that had a constant vacuum. In between that I had a small valve, if the valve was opened up to much the engine would die, try changing ports, are you running a Nikki carb? I need to take a look at that PDF doc again but the idea is that the gentle negative pressure caused by the vacuum port causes that minute amount of air to maintain atmospheric pressure in the float bowl thus allowing the carb to run more efficiently.Too much vacuum and you kill the engine and too little and it will not have an effect. It sounds like your setup is not correct. I would take a look at the manual again.

Posted: **Mon Oct 29, 2018 7:52 am**

Andy I will be keeping an eye on my sparkies - have taken them out to get a baseline prior to fiddling around.

Luke I have the Nikki and have also used the exact port you used, it is just out of the picture below.

Lines going through firewall:

Needle valve in cab:

: 2.jpg (25.05 KiB) Viewed 8102 times

I have now implemented the vent although I still can't get the motor to die making it difficult to tune correctly... I made two different sized holes in a small copper tube and depending on how far onto the copper you push the rubber tubes on either side, you can utilize the small hole, larger hole or both holes as the vent (or none at all).

Do you think my vent is large enough?

Posted: **Mon Oct 29, 2018 8:37 am**

So I think that 1) You have a port that does not provide constant vacuum, try messing around with this as I found this to be the most effective change to the mod, 2) You need enough of a suck to keep that constant vacuum on the float bowl and allow the atmospheric pressure to be constant, perhaps the vents are stopping you from achieving this, try delete the vents, I know the float bowl does breath through the Outer Vent Control Valve as well so you shouldn't have any issues with the fuel being sucked out the vent. see H8PVMNT's thread here for more info on that. http://board.marlincrawler.com/index.ph ... =100917.30

Posted: **Tue Oct 30, 2018 7:31 pm**

Alrighty, so I have checked the vacuum port over the rev range and it gives a decent pull throughout. The problem I seem to have is another vent into the float bowl aside from the top vent over the secondary barrel and the outer vent cv. My ovcv works. With the motor running and a tube connected to the top vent, I can suck freely on the tube with no resistance (and a lot of fumes in my face). I even tested this with the ovcv removed and blocked with my thumb.

Where else does the float bowl vent to?

Posted: **Tue Oct 30, 2018 9:59 pm**

From me blocking holes and H8PVMNT it appears that the OVCV system vents the bowl through its valve to the exterior (charcoal canister in murica) as well as to above the air horn (not through its valve). The internal vent runs through the rectangular passage visible when the ovcv has been removed. Blocking this stops my problem of the additional bowl venting - I cut a piece of rubber to size and shoved it in there.

It is possible to just get the motor to stall and tune now, although I am still fazed about the tube vent so have omitted it even though the manual implies that it does not exactly act as a vacuum leak.

We shall see how it performs:)

Posted: **Wed Oct 31, 2018 10:19 am**

Any modification that has the effect of leaning out the mixture will result in lower fuel consumption. With a petrol engine the mixture serves to cool the combustion process i.e. richer will burn cooler and leaner will burn hotter. It is possible to lean out an engine to the point that the exhaust valves and valve seats start "burning" - actually eroded due to the high temperature of the exhaust gases.

Posted: **Wed Oct 31, 2018 11:47 am**

Exactly. Do as you said and keep an eye on those plugs regularly and if you see the slightest sign of erosion on the electrodes or even the rim of the plugs, you must know that your valves / seats have already suffered a little as well. Fitting an EGT gauge might be helpful.

Posted: **Wed Oct 31, 2018 1:07 pm**

Tim86 wrote: ↑Tue Oct 30, 2018 9:59 pm From me blocking holes and H8PVMNT it appears that the OVCV system vents the bowl through its valve to the exterior (charcoal canister in murica) as well as to above the air horn (not through its valve). The internal vent runs through the rectangular passage visible when the ovcv has been removed. Blocking this stops my problem of the additional bowl venting - I cut a piece of rubber to size and shoved it in there.

IMG_20181030_200433-800x600.jpg

It is possible to just get the motor to stall and tune now, although I am still fazed about the tube vent so have omitted it even though the manual implies that it does not exactly act as a vacuum leak.

We shall see how it performs:)

I am really interested in what the outcome will be. My carb was a bit shot so another approach might be helpful.

Posted: **Wed Oct 31, 2018 1:17 pm**

Thanks for the advice, I will play it safe and check regularly. Correct me if I am wrong but another sign will be the currently grey/tan colour of the ceramic changing to white. Have also ensured my float level is slightly above middle. Luke did you happen to scope out your sparkies during the time you ran the enhancer?

The enhancer manual's main focus is to get the fuel to vaporize better and reduce the intake of liquid fuel - apparently only fuel vapour combusts fully whilst any liquid fuel within the cylinder does not therefore it gets sent out the exhaust unused. The liquid fuel also does not aid in cooling, it apparently is just there along for the ride. The manual's implemented vent and existing float bowl vents will serve to lean out the mixture in my view, hence the reason I was so keen to remove them all and only utilize the 'vacuum balancing' part of the system. OVCV opens up the bowl only when the motor is off so we shouldn't have a problem of pressure building up after switch off.

I am by no means a carby fundi, neither do I often pursue these types of 'free energy system' claims as they are usually drivel, but this piece of literature does seem rather in depth and reasonably profound. It would be interesting to hear what some more people with greater carb experience have to say after reading it.

Posted: **Wed Oct 31, 2018 1:45 pm**

Tim86 wrote: ↑Wed Oct 31, 2018 1:17 pm Thanks for the advice, I will play it safe and check regularly. Correct me if I am wrong but another sign will be the currently grey/tan colour of the ceramic changing to white. Have also ensured my float level is slightly above middle. Luke did you happen to scope out your sparkies during the time you ran the enhancer?

The enhancer manual's main focus is to get the fuel to vaporize better and reduce the intake of liquid fuel - apparently only fuel vapour combusts fully whilst any liquid fuel within the cylinder does not therefore it gets sent out the exhaust unused. The liquid fuel also does not aid in cooling, it apparently is just there along for the ride. The manual's implemented vent and existing float bowl vents will serve to lean out the mixture in my view, hence the reason I was so keen to remove them all and only utilize the 'vacuum balancing' part of the system. OVCV opens up the bowl only when the motor is off so we shouldn't have a problem of pressure building up after switch off.

I am by no means a carby fundi, neither do I often pursue these types of 'free energy system' claims as they are usually drivel, but this piece of literature does seem rather in depth and reasonably profound. It would be interesting to hear what some more people with greater carb experience have to say after reading it.

To be honest I don't remember there being any issues, but my valve stem seals were in need of replacement and my carb was slightly messed.

Hilux 4x4 Forum

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