That’s all the travel it gives back there. Take the fuel nut off to allow max travel, then adjust the star wheel to take the tension off its spring. Then, it will have all the travel available. The screw on top will give it 100% fuel (21mm) to make it start quicker. For checking rack travel, the pump would have to come off to access the rack plug on the front.

It will allow it to get to the governed speed quicker. Some of these were so horribly adjusted, that they would barely rev to 2300. You would adjust the gov springs if you wanted more rpm. Very rarely does anyone ever want less rpm.

@@nevrenufhp Thanks, yes my truck was set at supposedly 180hp (which I tend to believe) at 2600rpm no load. I turned out the jam nuts a fair bit (there would be 2 or 3 threads sticking out past the 10mm but still). I also adjusted the little stopper screw on the backing plate. At the same time, I tried to set the max travel stop on the throttle arm, but the bolt was seized and broke. I plan to make a new travel stop, but I started the engine up to see what how things were looking. It will do well over 3000rpm now, and I would like to bring it back down. I just can’t tell if my problem was the travel stop, or the rack adjustment I made. P.S. I really appreciate the help, I used to ask you the odd question on Pirate4x4 - you are always so helpful. I appreciate all your work on these videos!

@@Xkekeskfndsmw , on a DT360, that’s normal. On a 466, just don’t hold that rpm for hours. Either can go to about 3400 before any valves start to float, so it’s just more useable rpm now. In one of my other videos I have a 466 hitting 3150 no load. Ran that way for 100k miles, until it went to auction. Just enjoy.

Gillett Excavating, LLC, this is the fuel rate adjustment. Some call it turning up the pump. That’s typical of adjusting the excess fuel screw on top. It dumps in fuel in the lower rpm but then goes back to stock fuel after that point. You can take the nuts off, if you have an intercooler/ aftercooler and have a pyro to watch.

nevrenufhp so if I have not adjusted the fuel adjustment on the rear of the pump like you have explained in this video, should I start by adjusting this?

Absolutely! It's one of the first things to do. I access it from the cab, through the dog house. Most pumps have a rounded tamper proof screw that needs to be drilled out. I use a 1/4"X18" drill bit to drill off the head, then replace the screw with a new allen headed one.

T. W. , what you are describing is the screw on top got adjusted. It needs to be turned back in, and this video's adjustment made. This is the real fuel adjustment. If it doesn't get too hot, you can take off the nuts.

Sean Smith , I use needle nose pliers to back it out. The nut isn’t on too tight. If there’s a nut behind it, break that one loose first.

@@nevrenufhp awesome, I'll give that a try. Thanks very much!

May have to use some sockets with a screwdriver end, and go thru the dog house in the cab. I used vise grips on the round(tamper proof) one

Adjusting the star wheel the wrong way will make it real hard to make any power. Last I remember doing one, the wheel spins toward the engine.

The top one dumps in fuel at low rpm, which was designed for quick starts. The one on the rear is fuel rate for the whole rpm band.

@@nevrenufhp thanks I understand kinda. The star wheel setting does the same thing but as I understand it's a bit more "prorated" then the other. I always thought that the aneroid setting was on the back where the main fuel jam nuts are. I guess I still don't understand what the difference is between the back aneroid setting and the the upper front aneroid setting. Also I am working on my truck right now. Is it safe to take the jam nuts completely off? I have boost and egt guages. I just didn't know if it would mess up the injection pump in any way or if it could cause a runaway.. Thanks for your quick help!

There may be a fuel supply issue, or something got turned the wrong direction.

Peek down in the opening. The star wheel should be just forward of the half way point. Half way across the opening. Farther forward is more power.

I've seen pictures of them, but never touched one. The pumps almost seem unique to Mack/Renault. All I can say is start making one adjustment at a time. More than likely it will be under that cover on top with the 4 bolts, if I'm remembering correctly.

This is the way the P3000 pump in the Fords adjusts. Except a late 92 and 93 will likely have the fuel plate adjustments like the Dodges. It’s hard to include all of em in the subject line.

@@nevrenufhp Thank you I know a little bit about diesels but not enough is there a way to tell if someone has been there before or is it like hope for the best and make the adjustments and is there a point of no return I really do appreciate you taking your time to answer my question my 7.8L6 is a 91 and it runs good has just about 89,000 miles on it burns clean no black smoke hardly once again Thank you will removing the muffler and running a 4 inch stack help I am not looking for 400 hp however the 7.8 marlin had 400 hp so I know that they got it from these engines but 50 more lb- ft would make me happy is there any way to do that without going down and dumping much money into the whole set up mine is a 210hp 601 lb-ft with a 4 speed auto

@@kevinkinsey6985 , running straight pipe will help. I made a couple videos of an F800 7.8 I used to drive that I got straight piped. They do sound good. You can take the nuts off the back and it still likely won’t get hot enuf EGT. It’ll be close if it’s heavy. To tell if anyone has been in it before, you will see the tamper proof screw chewed up or replaced. It’s one of the 2 screws to access the fuel nuts. The free mods certainly make it more pleasant driving.

@@nevrenufhp I thamk you very much yes it is a F800 15,630 is the last tare weight iI seen on it once again Thank you

There’s one of 3 varieties. One I see a lot is just one nut that you can back out with needle nose pliers. It’ll be a little stiff, but it’ll come out. You can just remove it all together.

jiemrvow a Stanadyne 781697 is the biggest factory injectors I can find. Most any injection shop can get em, possibly Napa. Otherwise, you can get even bigger from Columbus Diesel Supply.

+Redcat Racing of Texas The screw on top is responsible for that. The one under the allen plug. If you want, you can remove the nuts on the back of the pump. That'll give it all the pump has(without getting inside the pump).

So I have the screw on top backed out as far as possible without getting stuck when I rack it back and forth. I know when we talked before, you said it could just get taken out, but I don't know what that'll do.

+Redcat Racing of Texas , taking out the screw will allow the power to extend higher in the rpm. That adjustment was originally meant to aid in quick starts. Only effective in lower rpm. To fine tune it, screw the top one in 3 or 4 turns, then back out the nuts from this video.

+nevrenufhp so what if I take the screw out the top and pull the nuts off the back? Or would that just be a nightmare in the making?

+Redcat Racing of Texas . Taking both out will smoke a lot, but also make good power. If it's still weak, you may need to pressure test the AFC and the line coming from the intake manifold.

Is is stiff by itself(cable disconnected from the lever)? If it's within the pump itself, there's a few things that could cause it, and a pump shop would have to dig in to it.

nevrenufhp Yeah its doing it when its disconnected. It starts to get easier when it is driven and worked back and forth directly bu hand but then goes back if it sits for a month.

buildthings79 , my first hunch is moisture got in there, and has rusted the linkage inside.

nevrenufhp So that area of the pump is dry. Does it shift the rack closed? By the way I really appreciate your knowledge on this, Thank you.

buildthings79 , it is at about the top of the oil level. Yes, it does go down to the rack to kill it. If the rack was dry, your rpm and power would be sticky too. One possible other idea, is someone messed with the screw on top(excess fuel screw). If it is backed out too far, it will bind up during shut down.

I tried rebuilding and upgrading a pump, and I don't want to do another one. It took me about 4 months to get it finished, and I still have to send it out for calibration. May not see it for a couple more months.

Just leave that one alone. Most of the time you can just take the nuts all the way off. The pumps are so small on almost all of these. They wont send too much fuel in to hurt it, but still needs to be monitored.

There is 3 different setups that I have come across. The one you have, you can use needle nose pliers to back it off. Sometimes there’s a nut behind that. Sometimes it’s just that one round nut.

@@nevrenufhp So I should remove the round nut completely and then make the adjustment?

catalanojaa yes, remove it to make sure no other nut is behind it. You can just leave it removed anyway. It won’t get too terribly hot, but you do still need to watch the EGT

nevrenufhp I removed the round nut and backed out the 14mm nut as far as I could but I didn’t not notice any difference. How do you adjust the full fuel stopper?

catalanojaa , that is the full fuel. Take both nuts off. Then, back off the screw on top a few turns. It’s one of my other videos. Low rpm/ excess fuel screw. It’s not a lot of power gained, but it’s free. Some trucks only gain 10hp, and some about 40.

It holds back fuel until the boost kicks in. As you spin it, you will notice the wheel slowly going forward, giving less tension on the spring that's in there.

I have done the top fuel screw I backed it out about five turns on my 8.3 Cummins. Also was told to turn the star wheel inward towards the motor to full turns which I did. Should I adjust the rear fuel Adjustment as the video as well? And how far out should I back off that would you recommend one of your previous video somebody calls at the smoke screw if going to far out is that going to create a lot of smoke?

+Bruce Raub ; Yes, it can be done on the truck. I didnt have a truck close to me, so I bought this pump. Thanks for your kindness.

Thank you sir, now I have to drill out or get one of sockets machined!

+Bruce Raub . Or just remove the nuts all together

+Bruce Raub . There is no fuel plate. Just follow this video. The injection shop would be doing the same thing. It's this pump's version of the fuel plate. Back out the nuts for more power....all there is to it.

Awesome, thanks again !

Yes indeed

@@nevrenufhp you still messing with the 6.6??? you ever do anything with it/

adam sorell , I sold the one I had. I do still have the front mounts and crossmember for an F series.

@@nevrenufhp can ypu email me janaohio@yahoo.com or text 740 three65 095two

@@nevrenufhp nothing really in common with pickup and the medium duty. cabs look same but r different

All the adjustments are on my KZfaq page. I cover the gov springs, fuel rate, excess fuel screw, and timing. Also have a written version on my website: Low Buck Diesel Power. It's at freewebs.com/nevrenufhp

leonardo rivera Rivera , is subtitles ok? I also have a request for Portuguese. Will be doing both very soon.

English

Either fit some small vise grips on the bolt, or chisel the head off. It's just a 4mm coarse bolt.

there a star wheel when I take off that Allen head out do I move it forward or back I'm turning it with a flat screwdriver got it till it ran on its own ran rough though?

The star wheel moves forward towards the front of the truck. It doesn't change idle.

Is this mw the same as the 5cyl pump as the mercedes om617