well today was the first time that i was able to pull something with my truck. i had a mini trackhoe on a 20ft heavydutey utility trailer, and i couldnt get over 50mph. it would take off through 1st and 2nd real good and would take a while to hit 3rd, it would hold 3rd for a little while and gradually loose rpm's until it would shift down into 2nd again and do the same thing over and over. the whole time i was pulling it never smoked a bit, the only time it would smoke was when it would change gears,and it was just a little puff. i just had a top end gasket change done and new injectors installed, the truck runs good it just doesnt seem to have the power. im going to bring itn and see if i can have the timing set on it to see if thats it. i just think if thats it , than its a little to advanced. what do yall think it could be?

 

What was your towing weight? with 3.55 gears and an automatic the truck is only rated at a Total vehicle weight of 12,000 lbs, 6,500 is what your truck likely weighs.
Just the heavy duty trailer likely weighs another 6. A truck with 4.10 rear end and standard trans is rated for more like 17,000 lbs.
If you didn't see any smoke with that kind of load, and you don't have a turbo, you shoulkd have a pyrometer before turning up any fuel delivery, and yes get the timeing checked first. I just retarded mine today, check out post on super tuning with glow plug readings.

 

the trailer is basicly a utility trailer its just has the pipe side rails instead of the angle iron side rails. not to sure what the machine weighs its a little mini track hoe, its a pc35 kobelco if that helps any. i pull this machine everyday with a 2500 chevy and it will outpull my truck thats just kinda hard to believe. i would have to say something is wrong somewhere, just not to sure where. i would like to see if its the timing that is the issue, because i realy dont want to start turning the fuel up if i can help it. it might even be the pump is week with 200,000 miles on it.

 

If you were on flat ground, than I would be tempted to think that something is not quite right. In general it seems to be normal to see some smoke when at full throttle, if your not than the engine may not be getting all the fuel is should be. I think having the IP looked at would be a good start, and you can also check pressure at the the valve at the fuel filter. There should be 6 psi at idle if memory serves.

 

A Kobelco 35 weighs 8000 pounds in round numbers.
Lousiana is flat enough that you should have been able to hold 55 rather easily.

Back when mine was NA I used to pull a Bobcat 331 on a 3500 pound trailer rather often here in WV a good bit with my 86.
The Bobcat is the same weight class as the Kobelco, your trailer weight is the only variable that is not answered.
The only truck difference is mine is 4x4 with a 4 speed and has a dump bed on it.
It weighs 8000 pounds empty.
There was a definite smoke trail behind me up every hill, which is rather often here.

Since the VRV is mechanically controlled by throttle position, your automatic tranny will not let you go to wide open throttle without shifting down to second gear.

Here in the hills I just hit the highway, shifted into 4th and put the throttle on the floor before I started up every hill and it did OK.

I think your IP is getting weak if you see no smoke.
And the IP timing may also be part of the problem.

 

thanks dave i was hopping you would chime in on this one. ive been opperating equipment for about the last 10 years and ive hauled alot of them with 1 tons and lowboys and i know somethings wrong with the way it pulls. this is my first ford with a diesel engine in it and i know it should pull the wheels off of it. the trailer that i was hauling probley weighs about the same. do you think maybe the previous owner of the truck maybe turned the fuel down on the ip hoping that maybe it would burn less fuel. im not to sure where the fuel screw is, so i could tell if maybe someone tinkered with it. i do know i had my wife with me and i asked her to look at the exhaust pipe while i was pulling and she said there was no smoke coming out of it, and if there was it was only when it would change gears. i did notice that it starts smoking if you let it sit and idle for a little while. it used to to smoke alot before i changed the injectors and now none. so what do you think it could be other than the pump?

 

When you replaced the injectors, you retarded the timing because of the extra pressure it takes to pop them off.

Also I figure you are about due for an IP if the injectors made much difference in the way it ran.

The fuel screw is located on the passenger side of the IP on the inside.
It is behind a small plate that looks like home plate on the baseball field.
Two small bolts hold it on, 1/4" head if I remember right.
There is also a very thin gasket behind the plate, use caution when you remove it.
Also you will loose about a cup of fuel out of the IP when you remove the cover.

It is a bit hard to find the screw, it is on a shaft that rotates as the pump turns over.
When the timing mark on the harmonic balancer is in the 1 O'clock position you should be able to see the allen screw with a mechanics mirror and light.
If you do not see it, you need to turn the engine over 360 degrees on the crankshaft and then it should come into view.

It takes an allen wrench about 5/32" to turn the screw.
You need a good allen wrench, you don't want some cheap wrench that will round out the allen screw.
One flat in should be plenty, a little goes a long way on that screw.
Ideal setting is a very light black smoke trail when pulling hard, any more is just wasted fuel.

You could also benefit from a ram air setup to the air filter, I have a couple pictures of mine in my gallery in the mod album.

Do you hear anything like a rattle when you first start the engine and the timing advance is on?
You might also loosen the IP and turn it the width of the static timing mark top to the passenger side to advance the timing a little.
Once again a little is a lot.

The IP turns over once for every two revolutions of the crank shaft.

Pulling heavy loads often would be a good reason to get a pyrometer.
Turning the fuel up, adjusting the timing, and adding ram air would be three more good reasons.

Add a turbo and you will wonder what happened to the trailer, it must have come loose.

85 four door dually......I may have to come visit you about 3 am one morning.
That is about what I would like to find from someplace where the rust was not so common.

Most of the early 80's trucks around here have bad cab corners, fenders are shot and the door bottoms are about gone.

My cab is in good shape, but I need fenders and doors soon.

 

Based on my experiance with my truck, I changed injectors, got rid of the smokeing at idle, but did not change timing on my IP, I assumed new injectors timing should be back in line. After a 1K km I decided to change the IP as well, as it had 240K km on it and didn't owe me anything, I was amazed at the differance a new IP made. FWIW.
As per my previous post, timing is critical to power as well, good place to start.

 

well i just did a new top end gasket change cause the head gaskets were leaking water out the back of the head. when i removed the ip i put a scribe mark to put everything back together with. after i put everything back together it didnt have alot of pep but the smoking was gone, and it used to smoke like a freight train. i had talked to a buddy of mine and he had said to advance the timing a little, but he told me to turn it to the drivers side. so after i read what you had wrote this whole time i have been retarding the timing instead of advancing it. could it be so retarded that it doesnt have the power and isnt smoking like it should.

 

Possible, but when you are far to much retarded, you usually have some white/light grey smoke at idle.
With new injectors that would be reduced a bit though.

Retarded will have an effect on the power though.

 

yes at idle i do have a little grey smoke coming out of the exhaust pipe but not much. i went and looked at the ip marks and it is about an 1/8 of an inch to the drivers side past the other mark.

 

OK that is retarded, I would line the marks back up as a starting point.

 

thanks dave for the info, yesterday i adjusted the ip about a 1/16 of an inch to the passenger side of the timing mark. i went and test drove it on a bridge that has a pretty good slope to it, and it is pretty tall too. usely i can top it at about 45mph, and i topped it at 65mph so it is a lot better. i wish i still had that machine that i could test it with lol. what is the name of the machine that you use to set the timing with, and what degrees do you set it at. im going to call around and see if anybody has such a thing around here. i just dont want to bring it somewhere and they tell you they set it with a machine and didnt even turn a wrench on it. thats why i like to do everything myself.