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Old 11-28-2013, 03:52 PM
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Default Bosch VE Pump Info

Here is something I found that would be of some help:

VE44 general info:
The Bosch VE44 diesel fuel injection pump was used on the 89-93 Dodge Cummins diesel Ram trucks. There were two versions of the VE44 pump, commonly known as the ‘early’ and late’ VE44. The early pump was used in the non-intercooled 1989-1991.5 trucks, and the late pump was used on the intercooled 1991.5-1993 trucks. Generally there are no major internal differences between the two pumps, and both use the same Bosch DGK 121 rebuild kit. The two visual differences include the output delivery valves (the 6 output ports connected to the injector hard lines) and the KSB. Both are good pumps.

Differences between the two pumps:

Non-I/C pump - #426 114
- larger and longer delivery valves
- timing a bit steeper then the IC pump....1.4MM vs 1.25MM

I/C pump - #426 184, or #426 205
- smaller and shorter delivery valves

General Pump Info:
The two VE44 pumps will physically ‘swap’/bolt up. However, the output delivery valves are not common between the two pumps. The delivery valve thread pitch is different, so the hard lines must match the respective delivery valves. The delivery valves can be swapped from one pump to another in order to match, or vice versa - the hard lines can be swapped out to match the valves.
- The IC pumps will push more fuel that the non-I/C pumps
- The non-I/C engines had bigger injectors (9mm) than an I/C engines (7mm)
- The 9mm heads are prone to cracking
- 12mm head (or 13mm head?) is stock. 14mm is aftermarket

KSB = 'Kaltstartbeschleuniger' – which is German for “Cold-Start-Device”.

The KSB is the little round component about the size of a tall shot glass mounted on the drivers side of the injection pump. The early KSB and late KSB do NOT swap, nor do they have the same operating function.
The KSB is used as a cold start aid. It will advance the timing on the engine when cold, and is designed to provide substantial injection timing advance in the low engine rpms so as to improve engine operation / emissions when the engine is stone cold after start-up. When in the engine rpms come up, the substantial timing advance tapers off to a much smaller measure of advance. The KSB does not function after the engine coolant reaches ~160* F.

VE44 Non-Intercooled KSB.
Pre '91 engines used the ‘wax motor’ type KSB, called so because a pellet of encapsulated engineering wax/plastic expanded when heated to move a plunger, which internally advanced the timing. 1988 emission requirements required the timing to be advanced when cold, to reduce white smoke. The non-intercooled trucks have a "wax motor" that opens the bypass passage in the KSB unit. When the ignition switch is turned ‘on’ an internal heating element begins to heat up the wax, the expansion of which opens the bypass. It may also have a voltage reducing resistor, but I am not sure. The wax motor style does not open instantly, but relies on an approximate warm-up delay to simulate the time required for the truck to warm up. The KSB is located on the driver's side, low, and toward the front of the VE44 pump.

The earlier 89-91.5 (non-I/C) wax motor type KSB holds the valve open when cold. When the engine is started the valve is already open, increasing timing. As the engine warms the pellets melt and the valve closes. This type requires 12v to close and function correctly. Without 12v power, the KSB will remain on, which can be hard on the pump.

VE44 Intercooled KSB.
The 91.5-93 KSB works in conjunction with a thermistor sensor in the head. When the ignition switch is in the ‘on’ position, 12v power is present at the thermistor. When cold, the thermistor sends 12v power to the KSB solenoid, which opens the KSB. Upon starting the engine, injection pump internal case pressure will advance the timing. 12v switched power is required for the KSB to open and function correctly, and will turn off when the thermistor sensor warms up and opens the 12v circuit, thus removing 12v power to the KSB. If unplugged, the KSB will simply not function, which will only possibly make a difference when cold. Under 90 deg., voltage is applied to the solenoid, blocking the fuel return path, and using internal pump fuel pressure, advances the timing slightly. Over 90 deg., no current is applied to the KSB solenoid, fuel is allowed to return via the normal operating fuel path. The timing advances normally thru internal porting, and sliding plunger. Also, between the switch and the solenoid is a resistor, mounted to a bracket on the side of the head, that reduces the voltage to the solenoid down to ~ 8V (when current is flowing through it & the solenoid -- if you just disconnect the wire at the solenoid you will get battery voltage). The solenoid operated KSB works instantly when you connect & disconnect the voltage to it -- when it is working you can hear the engine speed pick up and drop off connecting & disconnecting it.

General info from the web that might be useful:

If you're going to try to build a 5.9L Cummins with a VE injection pump to make more than 400 horsepower, you'd better have some big injectors. The Bosch rotary pump only puts out about 17,000 psi of pressure versus more than 25,000 psi for '03-and-newer common-rail injection systems. This means that since there is no way to up the pressure to increase the amount of fuel that is sprayed into the engine, more volume (larger injectors) is your only solution.
Lucas Prince of Darkness injectors (commonly referred to as POD's) are a good starter injector, although they are smoky, and your mileage may suffer. Dynomite Diesel also offers injectors for first-gens that are a bit more expensive, but they make for a great daily-driver injector, and can still make good power. For those sled pulling guys who aren't worried about smoke or EGTs, custom six-hole injectors with .016-inch or .018-inch orifices (referred to as 6x16s or 6x18s) are available from places like DieselTuff, Scheid, Buddha Power, and New Era Diesel.

Injection Pump
There are some simple tweaks you can perform to the VE injection pump to get an extra 100 hp. In the last few years, people have started making custom parts for these pumps to increase their fuel output even more. Brian Block, one of the original VE gurus, designed a 14mm injection pump head that can flow a lot more fuel than the stock version. The upside to the 14mm is a 100-horsepower increase over stock; to date, the only VE trucks over 600 horsepower at the wheels have used Brian's pump heads. Rocken-Tech is another company that builds parts for the VE, and their 4mm cam plate and 14mm head have also been used successfully at power levels over 400 hp. With either of these 14mm heads, an ultra-high-flow lift pump is necessary to maintain injection pump longevity.

Intercooled vs. Non-Intercooled
If you plan on towing, it's easier and cheaper to start off with a later, '91 1/2-'93 intercooled truck. The intercooler will keep EGTs in check, and the extra Overdrive gear will help fuel economy. Oddly enough, non-intercooled trucks had much larger injectors, which means they can still make decent power on a set of stockers. Power Stroke intercoolers can be made to fit first-gens, although water injection also does a good job of cooling the incoming air. If you find a screaming deal on an earlier model, go for it. If not, hold out for an intercooled truck.
Non intercooled trucks built before January 1, 1991 have larger injectors(9mm) and will get more boost with pump tweaking alone than the later model intercooled trucks with the 7mm injectors.

There are 4 main adjustments on the VE pump:

Low manifold pressure (boost) fuel delivery adjustment
This adjustment is fairly simple and will help considerably around town at low engine speeds and low boost conditions.
There is a small cap in the center of the 'fuel-control device' atop the pump (the 'appendage' that is plumbed to the intake manifold and restricts the amount of fuel injected until the manifold pressure is above atmospheric). This cap can be readily removed with two small screwdrivers and a gentle rocking motion. Beneath the cap is a torx T-25 screw and a lock nut that holds it. The locknut is 13 mm and has a 'break-away torque' of around 100 in-lbs. Turn the T-25 screw 2 turns clockwise and tighten the locknut to 125 in-lbs. For additional fuel (and smoke) the screw may be turned farther (CW). Back it off (CCW) to reduce smoke. NOTE: this will increase the exhaust temperature by about 75 degrees F on long grades. Clean the plug with CRC Brake cleaner and seal it with LocTite pipe thread sealant with teflon. Externally, it will appear stock.

Full load fuel delivery rate adjustment
The main adjustment is found under the AFC diaphragm that is held on with a 4-screw cover. MARK THE POSITION OF THE DIAPHRAGM, then remove the diaphragm -- there is a stamped tick mark on it, so use a magic marker or scribe to note the position of the diaphragm vs. housing. Remove the diaphragm and shaft, and note the shaft is both tapered and on an eccentric. Usually, rotating the shaft 120 degrees clockwise will cause the wear to go to the richest (smallest diameter, effectively) part of the shaft. You may want to start at 90 degrees and then go farther if that does not produce the power you want. The farther you go, the higher and faster EGT will climb. The fuel stop part rubs up and down along this shaft, and note the way to install the shaft that allows maximum travel of the fuel stop part that hits this shaft and is perpendicular to it.
Just pay attention and mark stuff so you can put it back the way it was, and you should be able to figure it out just fine. After adjusting the diaphragm eccentric, the low boost fuel rate may need to be adjusted slightly to reduce low speed smoke.

AFC Star Wheel Adjustment
Under the AFC diaphraghm and spring is a star wheel adjustment which sets the spring tension on the fuel load delivery rate diaphragm. If your star wheel (under the AFC spring) is set too high, the delivery rate pin won't move downward as it should with increasing boost levels. Turning the star wheel up (counterclockwise) increases the spring pressure, and slows the delivery rate. I'd suggest turning the star wheel down (clockwise) in 1/4 turn increments until you smoke, then back off (counterclockwise) till smoke is gone to your satisfaction, or smoke on under power, a black haze, not a black soot cloud. The retaining lock spring doesn't have to be removed, the star wheel will rotate with a small screwdriver gently placed and pried between the wheel and it. Note the location of the wheel, mark it, and count any turns for reference. Remember: Star wheel down=less spring resistance=increased fuel delivery rate.

Full Power Adjustment
Unless your AFC or diaphragm is way out of its proper setting. This is all you should have to adjust.
On the rear of the pump, partially concealed by the fuel lines, and under a plastic cap is another adjustment screw. Remove the plastic cap, remove the metal collar tack-welded to the screw, loosen the jam-nut, and turn the power adjustment screw clockwise about 1 to 2 turns. After turning the Full Power Adjustment, you may need to re-adjust the Smoke Adjustment Screw to reduce low speed smoke, and the idle screw or throttle linkage to correct the idle speed.

If your smoke is only at full throttle load - back off the full load screw.
If your smoke is at low end thru pull-up - Back off the smoke adjust screw on the top of the diaphragm housing. If you have dramatically adjusted the "star wheel" (the cogged adjusting wheel under the diaphragm) it can have the same effect, as even very slight boost will cause it to move to "full fuel", instead of waiting for the turbo to spool up a bit. Adjust the star wheel back a bit to reduce the smoke level.
If smoke is heavy at immediate start-up - fine adjust the smoke setscrew.

Fuel lines. As viewed from the back; clockwise from 11-o'clock position: 2-6-3-5-1-4
1996 RAM "Custom Ground" 100 plate 3/4 forward, 300 injectors, 16.5° timing, Goerends Auto = 365HP, 833TQ Third Gen Rims, Aluminum Headache Rack
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