New pump Question

[MEby]

For those of you who read my earlier thread, I did get the truck running. I was a combination of dead lift pump, bad fuel supply line, and extreme advanced timing(which was due to me forcing the gear over the woodruff key and shearing it of ). Now it runs well(although it seems to miss at idle a little, but pulls all six in at anything above idle) but power is way down since the pump was rebuilt. Is it possible when they rebuilt the pump that by putting everything back to spec that now it would flow less fuel now after its rebuilt than it did before the rebuild ?



It seems like i'm getting less fuel for these reasons, max egt is now 300 degrees less than what was previously possible(1200).

Boost will not go over 18 lbs(max was previously 28lbs).

And lastly at my set distance where I test my vehicle's, it goes a full 10mph slower than it did before in the same distance.

A boost leak would only result in high egts, right?

The injectors tested out perfectly.

No leaks in the high pressure lines.

The fuel supply line seems to be ok(does'nt appear to be all rusty).

Off the line I would say it pulls as good now or better than before. It seems around 1500 rpms or higher that performance is just not there. Although the last several sentences would be my butt meter talking.

What exaactly am I missing?

 

[dpuckett]

Do you ahve a fuel pressure gauge? If not, get one. I have heard of bad LPs off the shelf.



That said, unless you specify that you want fuel settings left alone, you will likely get less power than you had before, esp if you had turned some screws. 18psi and 900EGT sound about right for stock or a hair above. Kinda lethargic and lazy feeling no matter what you do to the pedal? The no power above 1500RPM puzzles me. The pumps I've had redone gained all kinds of poop and go after about 1600RPM up to the governor; and were no slouches off the line, either. Maybe the shop got something wrong internally. What is your timing set to?



Daniel

 

[TBurow]

my truck is currently rough at idle with a rebuilt pump and injectors but power is great the rough idle comes and goes and sometimes is worse than others i am thinking i have an injector leaking or sticking and just bought o\a pop tester to test and clean the injectors, i will let you know how it works out after it arrives. anyone in the area is welcome to come by and use it if needed.

 

[MEby]

Do you ahve a fuel pressure gauge? If not, get one. I have heard of bad LPs off the shelf.



That said, unless you specify that you want fuel settings left alone, you will likely get less power than you had before, esp if you had turned some screws. 18psi and 900EGT sound about right for stock or a hair above. Kinda lethargic and lazy feeling no matter what you do to the pedal? The no power above 1500RPM puzzles me. The pumps I've had redone gained all kinds of poop and go after about 1600RPM up to the governor; and were no slouches off the line, either. Maybe the shop got something wrong internally. What is your timing set to?



Daniel

I do not have a fuel pressure gauge. The pump has the fuel screw maxed out just like it was before the rebuild. The pump technician said it flows 98cc with the fuel turned all the way up and said that stock was 86cc. I would'nt say that it doesnt have any power after 1500 rpm, but I think that its not pulling as hard from there on up like it used to. Internally the shop said it is set 1/2 of a millemeter advanced. I set the timing on the truck to what felt and sounded the best by advancing and retarding it 6 or 8 times (redneck method) .

 

[dpuckett]

I dont know what head they put back in there, but 98cc is nowhere NEAR maxed out. Mine was set up for ~160. Stock is either 74mm (intercooled) or78mm (nonIC).



What in the heck is this 1/2mm, 1mm, etc, advance I keep reading about? Did I miss something in VE101, or is it just shops trying to pull one over on people and/ or not explaining stuff very well?



Daniel

 

[MEby]

What in the heck is this 1/2mm, 1mm, etc, advance I keep reading about? Did I miss something in VE101, or is it just shops trying to pull one over on people and/ or not explaining stuff very well?



Daniel

All I know is the shop guy said they advanced the pump internally by one half a millemeter. Is he pulling my leg?

 

[PToombs]

Did I miss something in VE101



Daniel

That's what you get for trying to set your timing! :-laf

 

[MEby]

Mine was set up for ~160.



Daniel

Set up how? You dont have one of the KTA Special's... ... ... ... do you?

 

[DGoyer]

Today I finally got the time to work on the VE. I had the local diesel shop
check the injectors on my 16,000 lb. delivery vehicle. He said they are in perfect shape, just turn up the pump. He pulled out a pump and showed me the fuel screw location. Well maybe at 40'ish my memory isn't like it used to be. After printing out a VE picture, and several trips in and out of the house. I found it
popped the plastic cap and turned it in one full turn. WOW, the thing idols at about 1,700. So more trips back and forth on the net, I found it how the hell
do you move the screw? I can see it fine and that is where it ends, got the nut loose can't turn screw.

 

[PToombs]

Jeez Dave, don't you have a VE guru nearby? :-laf

I had to heat my screw with a torch to burn the paint, and used a brass brush to clean it. I think I had to warm up the casting just a little too. Lotsa Blaster. I use a 1/4 inch socket and ratchet with a driver bit. Took it out, neversiezed it.

 

[DGoyer]

Well I just spent 56 min. with a hacksaw blade in a pair of vice-grips, presto
1/8 inch gone idle down. This screw is between the engine and pump. About
3/4 inch to view it. can't wait till tomorrow to get her out.

________________________
Dave

 

[PToombs]

P. S. - take the return line off, then use something to tie it out of the way. When you get the screw out, put it in from the other end, adjusts easier.

 

[DGoyer]

That is what that is, the return line right exactly in line with the slotted head of the bolt. Every time I look at one of those lines they break.

 

[PToombs]

Be brave, young scout!

 

[DGoyer]

Well I came home for lunch, took the old girl out for a test run. Wow, the boost stayed right at 30psi exhaust 950 post turbo. Problem, I came back home and parked tapped the pedal and she ran wild!! Had to turn off key, re-started all ok. did this several times, if you tap the pedal it comes down when you push just a little more away we go. Always comes down after key is turned off, did turn the screw in to much?

 

[MEby]

yes, you turned the screw in a little to far. back it out a little till it dosent do that any more

 

[DGoyer]

I turned the screw in 1/4 turn out, now it pauses for a second and drops down. The guy's at TST said they never herd of this happening. All is well now.

 

[MEby]

I turned the screw in 1/4 turn out, now it pauses for a second and drops down. The guy's at TST said they never herd of this happening. All is well now.

you might even turn it back a hair more. I think its a fairly common thing to happen even though my pump was ok with the screw turned in all the way. and welcome to the slippery slope of bombing your truck.

 

[dpuckett]

ALso, make sure you are getting full travel on your throttle rod- it may be sitting at the point of throttle shaft movement where it will seem to run away. (move my throttle about 1/4-3/8in from the stop and it will rev up to about 3600 in neutral) The blipping the throttle to make it come back down makes me think that is a possibility. And move your pyrometer probe to the manifold, it will be more valuable there.



DP

 

[sdstriper]

You might want to double check to make sure the pump lever isn't getting hung up on the fuel return line. That bolt in the top of the throttle lever was hanging up on my fuel return line occasionally, WOT eye opener.