I am trying to help Alex in Germany, 1987 F250 6.9L C6.

Alex approved of this post and I will direct him to this topic. Easier for me to write in English - Eng. is Second (or third) language for Alex

I do not have enough experience with diesel injection pumps and DB2 to give qualified advice about timing the I/P. Normally I recommend not to mess with it without having a timing probe and to get it precision tuned by someone who has the right equipment. Problems can occur if it isn't done right - like pump timing harmonics can induce more cavitation. However in cases like this one something has to be done.


We have already discussed the Fuel screw on the passenger side of the pump (with online instructions) and the adjustment screw behind the incoming fuel line at the center of the pump which I advised him not to change

Black smoke, apparently from the beginning of acceleration is the problem he is trying to correct, and today he told me that after work his truck would not start and had to be towed 40 km back home.

Alex does (very recently) have the original 1987 Ford Truck Shop Manuals on CD but probably without future updates and service bulletins. So if you have helpful advice directly from the manual, quoting the sections would be helpful.

The following is extracted from his email a few days ago:

Also all time I hit the gas pedal black smoke is coming from exhaust.

I am talking about this advance lever, it is fully screwed out for maximum travel.

The image he attached is from a DB2 article at Motor Mayhem. Below the image I will paste the relevant text from that page so readers will know what his initial question is about. If you already know about this automatic advance you can skip the descriptive text and read the rest of his email below.



Maybe you can give me more information about this.
Maybe bad timing? Worn injectors? Worn pump? Talking about this lever
Do you have any advice for me?

--------------

The is no mention of an adjustment in article that I quoted. .
I looked in the 87 Ford Shop Manuals (extensive section on DB2 in the ENGINE EMISSIONS DIAGNOSIS VOLUME H CAR TRUCK manual) but I didn't see anything about adjustment of automatic advance- I may have missed it- it's a big section. I also didn't see it in the Stanadyne PDF file on DB2 injection pump.

Alex has mentioned removing the Injection pump to make adjustments which I hope is not necessary

Any advice on how to cure the Black Smoke problem will be very much appreciated. That is the main issue. A troubleshooting sequence or standard sequence to correct this would be helpful.

From my viewpoint at this time: It may be that the only way to get this close to correct is to start with static timing- set it at the marks (which are only for assembly reference). He has instructions and images to do that (both methods- #2 by removing the oil filler-tube/cover and bringing the dowel (pin) to 12:00 o:clock looks like the easiest to me). THEN, estimate where the timing should be moved from that point and and move it that many degrees. The elevation there is around 1500 feet.

I've read that optimum timing for the 6.9L is between 5 degrees and 8.5 degrees BEFORE Top Dead Center. I don't know which way to move it from there for higher elevation, but I might start at 5 degrees BTDC and see how it runs, make some adjustments on the fuel screw to see what happens and go from there.

Or, if it is possible, set the fuel screw first to a known optimum number of turns from a stop and then set the pump timing to possibly get a more accurate pump timing, Then change the fuel screw or minor adjustments to injection pump timing that might be necessary.

What do you people who are experienced in timing without timing instruments think?

I think he wants to get the optimum timing first and later if he needs more power he can make some adjustments.


His truck not starting after a 40 km trip to work and then sitting all day may be a related issue although it's likely to be an air leak that is not related. He is using only a rear tank. I don't think a front tank is installed. I Know that he removed the rear tank recently for some cleaning and maintenance, filler tube etc. so maybe an air leak was created- also thinking about the switch-over valve. However, UNLESS you see how an air leak or work on the tank would create black smoke , lets avoid discussing that so the topic does not fill up with the typical air-leak advice.

Alex has not had this truck for very long, 3 months? He has a well equipped shop to work in with significant mechanics experience for someone under age 30 with a nice collection vehicles including a big old diesel Army truck (like an M31? so I think he can handle anything he needs to do mechanically, he just doesn't have adequate knowledge and experience yet with this American IH/Navistar 6.9L Ford Truck.

I will direct Alex to this topic by sending the URL in an email.
Thank you very much!

 

The photos you posted do not show the part of the Stanadyne pump that is often the first part to wear. That is the bore that the advance piston rides in and the pump that runs the advance. It is a weak spot in the pump. The automatic advance works by a rotary vane fuel pump that also is not in that photo. At engine idle speed - it makes less then 10 PSI and there is no auto-advance. As the pressure climbs with RPM the timing advances. Usually when it gets to around 60 PSI - full advance is in effect. Can be 10-12 degrees depending on the application. That is engine degrees - not pump degrees. Pump runs half speed and 5 degrees at the pump is 10 degrees at the engine.

The lever on the side of the pump is simply a mechanical device for changing timing and has nothing to do with the auto-advance.

Black smoke is unburned fuel. Can be from too much fuel delivery, lack of air, timing maybe way off, etc. How do you know someone did not turn up the fuel delivery by turning down the scew on the plunger leaf-spring? One turn of that screw by 1/3 a turn and that truck will blow black smoke often.

 

Lets see...
First off, if your friend messed with the screw on the Light Load Advance Lever on the side of the IP, he should first try to put it back the way it was. Unfortunately each pump is different(this is a calibration adjustment), but I would set it such that it's sticking out of the lever by approximately a dime's width on the back(where it contacts the piston).

If he's messed with the Light Load Advance Cam(the aluminum piece that the Light Load Advance Lever rides on; it's on the throttle shaft at the top of the IP), that needs to be adjusted. A 'close' method for this is:
1. Leave the throttle at the 'idle' position
2. Loosen the screw holding the cam in place, so the cam can be rotated freely.
3. Rotate the cam back and forth. You will see and feel where the lever starts to be moved by the cam. Place the cam just before this point and tighten such that the throttle can be moved just slightly before the lever starts moving.


Once that is done, we need to listen to the engine. How does it /sound/. Lots of clatter, no clatter when he accelerates? Does the clatter disappear when it smokes, or get worse?

If it gets worse or has tons of clatter, I would try retarding the pump(rotating the entire pump) based on instructions you've seen around here. If it's sounding like a gasser, advance it.


Once things are relatively close, I want some video. Fine tuning is possible without tools, but it requires listening to the engine under various conditions.

 

The black smoke issue may be as simple as turning back the max-roller-setting screw a bit. Might be an easy 15 minute fix with an Allen wrench (maybe).

 

Thank you for these very knowledgeable and helpful replies and for helping! I'm swamped with some work I need to do right now but I will be back within a couple of hours with some direct replies.

Alex is in a German time zone in Bavaria (about 9 hrs difference) getting near midnight there at the time I am posting this. It's a bit slow communicating back and forth due to time zones.

I'm quite sure that Alex will log in with some specific questions as they arise. He posted one topic here about his truck awhile back with some photos, and a few questions shortly after he bought it.

I'll be helping from the sidelines to help clarify information, look things up, find additional information, etc.

This shouldn't take long, I have seen that Alex is a good worker with a good well equipped shop space and he wants to drive this truck!

Thank you very much for your time and help!

 

A few "low tech" comments.

The timing being off is not going to cause black smoke when the engine is at operating temperature. White or grey smoke at times, yes.

Having the max fuel screw turned in too much will make it blow black smoke nearly every time you stomp on the pedal. But that has nothing to do with the engine quitting.

You asked about the screw in the back of the pump at the fuel inlet. That is the pressure adjustment for the rotary vane-pump in the back of the injection pump assembly. It has direct effect on how the automatic advance works. And yes - best to leave it alone since you have no way to check the advance to see what it is doing. I also suspect you have no way to even check the PSI of that vane-pump regulator. The only way to check that PSI is with a special adapter. That tiny bolt in the back that holds the little lock tab is actually threaded into a pressure-test port. It's a tiny hole and Stanadyne has a $10 adapter that you screw into it and then a standard test hose and gauge with standard 1/8" pipe thread.

 

No, it'll cause black smoke if too advanced, under load/throttle. I've /done/ it.
If you floor it, yes. If you are careful about how you throttle the engine, you can drive around with it turned all the way up and not have any black smoke.


Perhaps we're thinking about different things. There is a screw, covered by a red cap, near the top of the IP at the back(above the fuel inlet).
This screw affects the governor response and nothing else. The screw is actually a couple of inches long, with a smooth rod for most of it's length. The governor assembly rides on this rod, and the end pushes against a spring.

Adjusting this will change governor response -- how much fuel it adds when the RPMs drop. I ran into an issue with a sticky pump that wanted to die when I let it drop to idle from a higher RPM, but would idle fine if you let off slowly. I adjusted that screw in several turns, which had the effect of making it compensate more and prevented it from dying. It ended up making the pump feel more 'snappy'. Timing was not affected.

 

He can give me a call, I am at his time zone being Czech. I think the best way would be order a pump from RD performance, at least u be sure the pump is ok. I had the same issues with the tanks when one was droped. I assume it is the FSVnot sealing properly. I have a spare pump I can borrow, do not know anything about it, it is junkyard pump, plus I have another on the spare engine which was supposed to run prior pulling from the truck.

 

[QUOTE=Macrobb;15773788
Perhaps we're thinking about different things. There is a screw, covered by a red cap, near the top of the IP at the back(above the fuel inlet).
This screw affects the governor response and nothing else. The screw is actually a couple of inches long, with a smooth rod for most of it's length. The governor assembly rides on this rod, and the end pushes against a spring.
[/QUOTE]

The screw in the back of the pump I'm mentioned is for adjusting the fuel-pressure regulator that runs the auto-advance timing which is totally hydraulic.

Turning in the the screw - that flattens the leaf spring - that allows more plunger travel - to make more max fuel certainly can make a truck so it blows a puff of black smoke every time you hit the pedal. It's a situation I've seen come up many times on GM 6.2s and 6.5s as well as IH-Ford 6.9s and 7.3s. Also on many a John Deere tractor.

 

Hey there,

now I am here!

Thank you for your inputs!

I bought the Truck at end of September. Drove it home for 250 Kilometers and already noticed that there are some issues are waiting for me. :-/

- Air leak in fuel line (should be on the IP the lever on driver side.)
- Rear fuel tank missing
- front seems to have a hole (no, it is okay, it was grease from U-Joints and a old rubber hose)
- very low to near no battery charging (got two 100 Amp batteries in with 70 Amp Alternator will be swapped to 3G soon, nearly all components here)
- VRV valve missing on IP
- lots of white smoke after start and running Idle (seems to be CDR valve, already new, and much better)

So I startet to work up some things already.

So I did not change anything on the timing or pump at the moment.
What you can notice : If you pull up the rpm the "advance lever" is moving fully to its end position.

Also got an Detroid diesel running in an M1009 (6.2D) and there maybe I can check for compareing how it should move.

And in the same moment you move the rpm up you can see black smoke from exhaust. Also the engine is accelerating very slowly (idly?) moving up. 6.2 Seems to have more power than the 6.9 :-/

If you have any advice let me know, I am happy for every help I can get on this.

Thanks!

 

Call me 8 pm I am in Prag, Tschechien. 00420773922093 it is already with intl. prefix.
Jan

 

White smoke as you describe can be from retarded timing. Black smoke is usually from too much fuel delivery. As far as power goes when compared to a GM/Detroit 6.2 in a M1009? Should be no contest. Any 6.9 or 7.3 should have quit a bit more power. Even the military 6.2 that has a little more power then some civilian 6.2s. That military truck only has 3.08 axle gears hooked to a TH400 three-speed auto trans. What does your Ford have?

 

Dude I have driven a 6.2 diesel, no way it has nearly the power of the 6.9/7.3. Your pump must be really off or tired. It took me quite a while to adjust mine, but now I am happy. I just hauled 1. something ton of wood, it did great, in fact the truck loves to be loaded. then it is smooth ride, maintained 60mph on the country roads and highway, riding like a champ. And it is very quiet, The torque is fantastic, I just love the old IDI so much.

 

You misunderstood what JD wrote. He stated that any 6.9 or 7.3 has significant more power than 6.2 and also more power than military 6.2 - which (military 6.2) sometimes has more power than civilian 6.2

 

I said no way it has nearly the power of the IH engines, what I wanted to say that I have driven several ones and they are not very good engines powerwise. I am glad I did not buy the Chevrolet K30 with 6.2D as it was my first choice considering diesel truck.