Is it normal for a 93 6.5TD to have better response on the highway giving it half pedal depression than dropping the hammer?
I have that issue and have been wondering if it is normal?
Thanks,
Mark

Before I turned the leaf spring in on the '93 it seemed dead at 75%-100% pedal. What exactly would you say it is doing?

At part throttle the Light Load Advance mechanism will push the advance further than the speed advance you get with Wide Open Throttle.

The way it should work is when your maintaining speed, the fuel delivery rate cuts back and you get more advance. If you are getting more advance at the wrong time it could be timing chain wear or face cam/roller wear, in which the pump either needs to be advanced or rebuilt.

Before I turned the leaf spring in on the '93 it seemed dead at 75%-100% pedal. What exactly would you say it is doing?
You got me on the leaf spring thing.:eek:
But in regards to main question, if I'm driving on the highway or even the main roads, I try to get out of my own way to get around some bullet head that is doing 25 in a 35, and the truck seems to roll better if I only give it half pedal and if I drop the hammer it takes way to long for it to get up to speed. Could this be an issue of my TC?
Mark

At part throttle the Light Load Advance mechanism will push the advance further than the speed advance you get with Wide Open Throttle.

The way it should work is when your maintaining speed, the fuel delivery rate cuts back and you get more advance. If you are getting more advance at the wrong time it could be timing chain wear or face cam/roller wear, in which the pump either needs to be advanced or rebuilt.
TDG,
I was going to replace the timing set a little bit ago, but was advised against it due to it being newer and not having a bit of slop to it when pulled and checked(when the water pump was last replaced, 2 months ago). As for the pump, I don't know. I will not advance it until I get my gauges in it and maybe even until I get my new tank. It will be done by our buddy(your student) Dan and I one of these weekends when we can get together.
Thanks,
Mark
I am open to any other ideas. Could TC have anything to do with this or maybe my rear-end?

Or perhaps a blockage in the filter housing or pump itself. Mark, you had rust showing up in your filter, right?

My 93 acts exactly the same way. From the "seat of the pants" feel, it seems to accelerate faster at about 1/2 pedal than at full pedal. Engine only has about 15K on it and the injector pump was replaced about 1000 mi ago. Has acted this way since I bought the truck so I just assumed it was "normal".

Boost pressure also spikes initially (6-7 lbs) at at 1/2 pedal, but drops at full pedal to about 2-3 lbs.

Before I turned the leaf spring in on the '93 it seemed dead at 75%-100% pedal.
You got me on the leaf spring thing.
Leaf spring he's referring to is the one inside the pump that sets the travel limit for the shoes/rollers/plungers on the rotor. Turning it in spreads the leaf spring giving you more travel and more fuel.

Most of what you guys are experiencing, is the nature of the beast, Light Load advance is controlled by the face cam that moves with the throttle lever.
About 70% throttle and up is full retard position on the face cam, meaning your only getting speed advance, which is set to 4 deg @ 3400 on a 4911.

At lower engine speeds, say about 2000 and lower, With the pedal on the floor you will be at 0 Advance, let it off to maintain speed and fuel delivery will cut back and LLA will move to about 5 deg (depending on engine load).

Damn that sounds like you copied that straight out of a db2 service manual. I m sure everyone knows what that means

Hmmm.....maybe I can get some sort of visual (graph) explanation, plotting engine RPM vs Advance at WOT and L.I.
I'll see what I can come up with...

TDG You might want to tell everyone thats pump degrees not engine degrees.

Ahh, good point, Pump rotates at half crank speed, so advance movement of the cam ring is actually double the difference in injection timing.

Also why static timing is so sensitive, 1 deg is really 2 deg.

To all,
Went and had a couple of checks today and seems to be having all the symtoms of a torque converter. I am going to start a thread in the supporting vendor area to see who has a good one at a decent price (while I won't lose my a$$ in shipping/preferably local). If anyone has an idea where I can get one at a decent price, please let me know. I do want one that is going to last though since I will probably paying out the hind end for labor.
By the way, if anyone(probably local or it may defeat the cause due to shipping) needs tires at at a wholesale price. Pick-up only--no mounting. I just hooked up with a place here in Ohio that gave me a price of $114.00 ea. for Toyo LT 265/70 or 75/16.. and $32.15 per tire for the ones I'm running right now.
Thank you all for the info and advise and I know I will have more questions soon.
Thanks,
Mark