Adjustments to fuel setting

[nforce]

I was up at Rob Lassmans the other day with my 81 and we adjusted the fuel setting, turning the screw out close to half a turn (Rob correct me if I am wrong), and the immediate effect on the black smoke was amazing. Turbo was running great and no change with the fuel setting change. It was still stock from with the little clip on it so it did not look like it had been adjusted.
I also seemed to get an immediate improvement in fuel economy. I am now getting around 600km per tank so likely around 650 with the 255/86/16's on the truck.

Anyway, if you want your trucks working top notch, i would suggest seeing Rob. He is terrific. And he does not mind you poking around with him and learning at the same time.

btw, i had the injectors cleaned, oil changed, clean air filter....so it was the fuel setting..........

thanks and anyone who wants information on this issue just contact me back


Dave

 

[brownbear]

so you increased or decreased your fuel load?

 

[Tapage]

so you increased or decreased your fuel load?

seems to decrease the fuel ratio ..

 

[nforce]

fuel load was decreased

Fuel load was decreased, about 1/2 a turn

 

[Martin White]

Dave, I think I need to do the same thing on my truck. Can you tell me what % your fuel economy improved by making this adjustment? Was there any noticeable loss in power? Are you going to try turning it down any further? I have very high EGT's and I think this may be the problem, and may partly explain my relatively high fuel consumption.

 

[brownbear]

So giver a try Martin... And post some pics

 

[Lantec]

So giver a try Martin... And post some pics

Yes, please do.

I'm kinda thinking of turning down fuel too cause I can hit 1200F pretty easily going up a big hill to my school and I'm only averaging 19 US MPG.

I looked on your pics and i can't find it on mine. Maybe I'm not looking hard enough lol

Is it on the left or right side of the truck?

Ok, I checked on my truck and this is the closest thing I can find

Should I be alarmed if this is the correct screw and there is no nut holding it?

 

[Lantec]

Any one have ideas if that's the fuel adjustment screw?

I can't even find that in the 3B manual

 

[Martin White]

It looks exactly the same as the fuel adjustment on mine. I have made some adjustments. Dramatic change in power. I need to find the sweet spot now between power and fuel economy. I'll post some information on that later. I turned it down 1/2 turn and I think that may have been a little too much. The adjustment takes about 2 minutes so it's easily changed. The impact is immediate, so you know right away where you stand.

 

[Tapage]

I strongly recomends for tune your fuel install a pyro .. and watch your EGT throught the proceess.

 

[Lantec]

It looks exactly the same as the fuel adjustment on mine. I have made some adjustments. Dramatic change in power. I need to find the sweet spot now between power and fuel economy. I'll post some information on that later. I turned it down 1/2 turn and I think that may have been a little too much. The adjustment takes about 2 minutes so it's easily changed. The impact is immediate, so you know right away where you stand.

Did you also have to unscrew the nut at the end?

EDIT: Yes, that was a stupid question of me.

I adjusted it about 1/2 turn down and I'll see how it goes. Thanks

 

[BreckenridgeCruiser]

If it helps, check out the thread I posted. I have a good picture of the screw and Brown bear helped with a highlight. This is the 2B inline pump.

https://forum.ih8mud.com/showthread.php?t=112127

The screw needed to be turned IN on my 2B pump. I think it affects the fuel because by turning in, it moves the EDIC arm assembly closer to the fuel cut off location. It seemed to be just a mechanical effect on that EDIC lever, which operates a valve in the body of the pump that allows fuel in.

accourding to the manual, the EDIC arm should be way towards the front of the truck when you shut down, and way back when you start it up. It is somewhere in the middle when driving. Adjusting the screw adjusts the position for driving position.

I hope this helps. I had a bear of a time figuring it out, but now no smoke. I turned it down a little to much, but I don't mind the lessening of power until I install a pyro.

HTH!

 

[Martin White]

I think it's been said on another thread, but for continuity, I'll add it here. You need a 12mm deep socket (on my 1HDT it's impossible to get a wrench or regular socket on the big nut) to loosen the locking nut, and a 6 mm wrench (or socket) to turn the adjusting screw. It takes about 1-2 minutes to change your fuel setting.

The effect is immediate, and you know right away how it's going to drive. As for fuel economy, that will take longer to work out. If fuel economy increases or decreases linearly with power, it would be easy. But somehow I doubt it's that simple.

 

[Lantec]

I think it's been said on another thread, but for continuity, I'll add it here. You need a 12mm deep socket (on my 1HDT it's impossible to get a wrench or regular socket on the big nut) to loosen the locking nut, and a 6 mm wrench (or socket) to turn the adjusting screw. It takes about 1-2 minutes to change your fuel setting.

The effect is immediate, and you know right away how it's going to drive. As for fuel economy, that will take longer to work out. If fuel economy increases or decreases linearly with power, it would be easy. But somehow I doubt it's that simple.

I turned it down half a screw but I don't really notice a difference in power. I was turning towards the left, not sure if that reduces fuel or not on my pump.

 

[Martin White]

I'm pretty certain that counterclockwise reduces the fuel in all these pumps. I'm intrigued you didn't notice a difference. A little over half a turn on mine and the difference was huge. In fact, too much. I've since turned it back up a little. Still experimenting. I'm most interested in the effect on fuel consumption but it will take some time to work out a somewhat accurate measurement. It would be interesting to have access to an inline monitor - then there'd be instant feedback on fuel consumption and possibly other variables.

 

[Lantec]

I'm pretty certain that counterclockwise reduces the fuel in all these pumps. I'm intrigued you didn't notice a difference. A little over half a turn on mine and the difference was huge. In fact, too much. I've since turned it back up a little. Still experimenting. I'm most interested in the effect on fuel consumption but it will take some time to work out a somewhat accurate measurement. It would be interesting to have access to an inline monitor - then there'd be instant feedback on fuel consumption and possibly other variables.

I should take it on the highway first to see how it goes, I just drove to work and back which was like 5 minutes away, so I guess I didn't notice just yet.

 

[Martin White]

I noticed the difference just from a standstill. The effect was immediate and I could feel it in the parking lot. I turned my down over 1/2 initially and that was too much. I think now I have it about right.

 

[Lantec]

I noticed the difference just from a standstill. The effect was immediate and I could feel it in the parking lot. I turned my down over 1/2 initially and that was too much. I think now I have it about right.

It may have been I drive really slowly from the beginning to start with, I never really pressed past half throttle before I turned down the fuel.

On the way back from work today, I did try flooring it and it did seeem to lack a bit of power and EGT had a hard time reaching 900f.

 

[BreckenridgeCruiser]

My 2B pump needed a Clockwise turn to reduce the fuel load. Just to let you know all pumps are not counter clockwise to achive this...

K

 

[Martin White]

Ah, so much for that theory.