Adjusting fuel on 3B (1 Viewer)

[GregS]

I found this pic on another thread. Does it accurately describe the method for increasing/decreasing fuel on a 3B with the HAC system? Loosen the large nut and turn the entire "puck" to the right of it in the desired direction. Anybody have a better pic?
Thanks...

 

[cruiser_guy]

That will adjust how the HAC behaves with regards to fuel delivery. Is that what you're trying to do?

 

[roalco]

That HAC adjustment functions the same as the regular full stop capsule function, it only sets the maximum fuel (rack) stop position.
The screw the finger is pointing to is the injection pump bleeder screw (from the pump feed cavity).

 

[slammed41]

the fuel screw (centre of photo) is at the rear of the injector body. want more fuel? loosen (more threads showing) the screw.

 

[roalco]

Great pic, Slammed41! That is indeed the dreaded "full stop cartridge" (adjusting screw and locknut). Always a good idea to lock wire the nut after adjusting...

 

[Wedg3]

The HAC and the screw that slammed41 show have the same fonction. If you have a screw it's because you don't have a HAC. Tell me if I'm wrong ?

 

[roalco]

Yup, same thing, they both stop the fuel rack at a set, maximum, position, the HAC just reduces that position at altitude.

 

[GregS]

Thanks for all the responses.

I've got the HAC system and want to experiment with adjusting the amount of fuel after a turbo install. So if I understand correctly, I will be turning the HAC to increase/decrease fuel?

 

[eleblanc]

Thanks for all the responses.

I've got the HAC system and want to experiment with adjusting the amount of fuel after a turbo install. So if I understand correctly, I will be turning the HAC to increase/decrease fuel?

Yes, loosen the 27mm screw, and unscrew the HAC puck. I would recommand using a marker to mark where you place the puck. Go with 1/2 turn increments.

If you do not have a EGT to watch exhaust temperature, don't play with the fuel.

 

[slammed41]

If you do not have a EGT to watch exhaust temperature, don't play with the fuel.

X2...!!!

 

[GregS]

EGT and Boost gauges installed. Just looking to fine tune it a bit but not to send the egt's through the roof. Thanks for clearing it up.

 

[Lazman]

I too have excess black smoke on acceleration. So I need to tighten that screw (last pic on this thread)? I assume best to do this when the motor is warm...

 

[Lazman]

Mud is great! Did a little search and adjusted my fuel mixture. Did a few half turns and tested the rig each time. After 3 adjustments I was able to reduce the black smoke 90%. My 3B swap had a turbo initially and the fuel mixture was increased. I'm running non turbo for now. Coming from a B diesel to a 3B has made a significant improvement!

 

[Hilux safari]

Mud is great! Did a little search and adjusted my fuel mixture. Did a few half turns and tested the rig each time. After 3 adjustments I was able to reduce the black smoke 90%. My 3B swap had a turbo initially and the fuel mixture was increased. I'm running non turbo for now. Coming from a B diesel to a 3B has made a significant improvement!

I have the same problem you had. No smoke at start up or idle, but plenty of black smoke when I accelerate. I have a B diesel. Did you adjust the screw in the back of the injector body (as the picture above from Slammed41)?

 

[gerg]

Yes you can adjust the fuel pump screw or use less of the gas pedal.

 

[cruisedeisel]

Yes you can adjust the fuel pump screw or use less of the gas pedal.

THis is my theory for waste gates. WHy have a waste gate when you can just back off the throtle. Maybe stolen from tapage.

 

[gerg]

So that's not a bad idea if your turbo is oversized, but if you go smaller then you will be giving away power due to excessive boost or run the risk of overboosting and damaging your turbo. Boost always creates backpressure no matter how efficient your turbo is. If I clamped my gate shut, my turbo would begin to boost more than required around 2000rpm or so. Tuff to judge but its a guess. By 2500 rpm id be thinking id be getting close to 30psi which would be a bad idea for both compressor efficiency and thrust bearing life.

 

[Lazman]

I have the same problem you had. No smoke at start up or idle, but plenty of black smoke when I accelerate. I have a B diesel. Did you adjust the screw in the back of the injector body (as the picture above from Slammed41)?

That's exactly what I did.

 

[CptCanada]

So possibly beating a dead horse here and I apologize but to be prefectly clear, after loosening the lock nut on screw on the outer side of the pump, then in turning counter clockwise, increases fuel to the cylinders? The warning here was to not play with this unless one has a exhaust temp gauge but black smoke meaning more fuel, tho less efficient is safer correct?

 

[mano002]

So possibly beating a dead horse here and I apologize but to be prefectly clear, after loosening the lock nut on screw on the outer side of the pump, then in turning counter clockwise, increases fuel to the cylinders? The warning here was to not play with this unless one has a exhaust temp gauge but black smoke meaning more fuel, tho less efficient is safer correct?

yes, that is correct.