warning warning disconnect the vp44 fuel pump drain line … · 2019. 9. 4. · vp44 fuel pump....

9/3/2019 QuickServe Online | (3666193) ISB and QSB5.9-44 Troubleshooting and Repair Manual

https://quickserve.cummins.com/qs3/portal/service/manual/en/3666193/ 1/9

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General InformationThe fuel injection pump (VP44) is an electronic rotarydistributor pump. The pump performs four basic functions:

1. Producing the high fuel pressure required for injection2. Metering the exact amount of fuel for each injection cycle3. Distributing the high-pressure, metered fuel to each

cylinder at the precise time4. Varying the timing relative to engine speed.

A cam ring with three plungers, a rotor, and an electronicallycontrolled fueling solenoid valve is used to develop anddistribute the high pressure required for injection.

A worn or damaged internal transfer pump, plunger, or fuelingvalve can affect the pressure and amount of fuel injected, thusreducing the power from the engine. Generally, if the fuelinjection pump is injecting fuel from one outlet, it will deliverfrom all outlets.

VP44 Timing Principles

Timing in the VP44 is controlled by an internal timing pistoncoupled to a cam ring inside the pump. The timing piston ismoved by fuel pressure. The amount of fuel pressure in thetiming piston assembly housing is controlled by an internaltransfer pump and a pulsating timing solenoid valve.

As pump speed increases, the fuel pressure to the timingpiston assembly also increases. Based on the inputs from thefuel pump control module (FPCM), the timing solenoid valvepulses to vary the pressure to move the timing piston, whichresults in the cam ring moving to the desired position toachieve the commanded timing.

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Initial Check

The more pressure created by the internal transfer pump andtiming solenoid valve, the more the timing will advance;therefore, timing range capability is increased at higher rpm.

WARNING

Depending on the circumstance, fuel is flammable. Keepall cigarettes, flames, pilot lights, arcing equipment, andswitches out of the work area and areas sharingventilation to reduce the possibility of severe personalinjury or death when working on the fuel system.

WARNING

Do not vent the fuel system on a hot engine; this cancause fuel to spill onto a hot exhaust manifold, which cancause a fire.

Disconnect the VP44 fuel pump drain line from the T-fitting andplug it.

Disconnect the vacuum gauge plastic tubing from the cylinderhead's drain line and connect it to the VP44 fuel pump inletline.

Note : All fuel must be drained from all fuel lines, ifobserved.Apply the vacuum test to the fuel system and check thevacuum gauge. The vacuum can not exceed 381 to 508 mm-Hg [15 to 20 in-Hg].

If the system holds the vacuum (if the reading on the gaugedoes not reduce, the vacuum should not drop more than 2.54mm-Hg [0.1 in-Hg] in a minute), then there is no leak in the fuelsystem.

Note : The vacuum test is completed if the fuel systemholds vacuum for at least 5 minutes.



Preparatory Steps

If the system does not hold vacuum (the reading on the gaugedoes not hold and reduce to 0 mm-Hg [0 in-Hg], then there is aleak in the fuel system.

If the system does not hold a vacuum, check for leaks at theVP44 fuel pump.

Inspect the lines, fittings, washers, and VP44 fuel pump for anydamage. Replace and install parts that are damaged.

Contact a Cummins® Authorized Repair Location forreplacement and installation of the VP44 fuel pump, if required.

WARNING

Batteries can emit explosive gases. To reduce thepossibility of personal injury, always ventilate thecompartment before servicing the batteries. To reduce thepossibility of arcing, remove the negative (-) battery cablefirst and attach the negative (-) battery cable last.

WARNING

Depending on the circumstances, fuel is flammable. Keepall cigarettes, flames, pilot lights, arcing equipment, andswitches out of the work area and areas sharingventilation to reduce the possibility of severe personalinjury or death when working on the fuel system.

Disconnect the battery cables, negative (-) cable first.



Remove

Disconnect the fuel return line. Refer to Procedure 006-013 in Section 6. (/qs3/pubsys2/xml/en/procedures/53/53-006-013.html)Disconnect the fuel pump supply line. Refer to Procedure006-024 in Section 6.(/qs3/pubsys2/xml/en/procedures/53/53-006-024.html)Disconnect the 9-pin electrical connector from the fuelpump control module (FPCM).Remove the crankcase breather and gear retaining nutand washer. Refer to Procedure 003-018 in Section 3.(/qs3/pubsys2/xml/en/procedures/53/53-003-018.html)

Note : Doing the above will help prevent the fuel pumpkey from falling into the housing if it is loose.

It is recommended to bar the engine over so the keyway on thegear is at the 12-o'clock position when removing the fuel pump.This position can be found by taking the oil fill or fuel pumpgear access cap off, whichever applies, and aligning thekeyway in the fuel pump gear to the top dead center (TDC)position on the front cover. In this position the line on the fuelpump gear will be approximately in the 5-o'clock position.

Disconnect the 9-pin electrical connector from the fuel pumpcontrol module (FPCM).

Remove the fuel pump support bracket.

Remove the fuel pump gear retaining nut and washer.

Use Fuel Pump Gear Puller, Part Number 3163381, to pull thefuel injection pump drive gear loose from the pump driveshaft.

https://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/53/53-006-013.htmlhttps://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/53/53-006-024.htmlhttps://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/53/53-003-018.html



Clean

Note : Do not drop the drive gear key when removingthe pump.Remove the four mounting nuts, and remove the fuel injectionpump.

Once the damaged fuel pump is removed, it must be properlylabeled with the Engine Serial Number (ESN).

Record the engine serial number (ESN) on the wire tag (1)provided with the replacement pump. Insert the tag into theplastic sleeve if one was provided to protect it from fuelsaturation. Securely fasten the tag to the damaged pump byinserting the wires through one of fuel pump mounting boltholes and twisting wires together.

Drain the fuel from the damaged pump.

Use the plugs and the caps from the replacement pump to plugthe threaded holes and cap the delivery nozzles on thedamaged pump.

Place the damaged pump in a plastic bag to prepare forshipping.

Use a clean, dry cloth to wipe all of the oil off the back of thegear housing mounting surface and pump housing.



Inspect for Reuse

Install

Inspect the mounting surfaces for damage.

Inspect the fuel pump mounting o-ring for cuts or damage.

CAUTION

The driveshaft must be clean and free of all oil beforeinstallation. Failure to do so can result in the drive gear

slipping on the shaft.

The keyed gear and shaft allow for the fuel injection pump tobe installed in any position, as long as the markings on thefront gear train align and a gear has not slipped.

The Woodruff key part number (identification code) is locatedon the data plate on the side of the VP44 pump. The correctkey number must be used so correct timing can be achieved.

The arrow on the key must be pointing toward the fuel injectionpump and away from the gear housing.



Use an evaporative cleanser (e.g., brake cleaner, isopropylalcohol) to clean the pump shaft and gear bore.

Note : Barring the engine so the keyway is at the 12-o'clock position will aid in aligning the key into thekeyway.Note : The fuel injection pump shaft must be rotated toalign with the keyway in the gear.It is recommended to bar the engine over so the keyway on thegear is at the 12-o'clock position when installing the fuel pump.This position can be found by taking the oil fill or fuel pumpgear access cap off, whichever applies, and aligning thekeyway in the fuel pump gear to the top dead center (TDC)position on the front cover. In this position the line on the fuelpump gear will be approximately in the 5-o'clock position.

Install the pump. Make sure the key does not fall into the gearhousing. Take care not to damage the pump mounting o-ring.

Note : When installing the fuel pump, the dowel in theback of the gear housing must line up with the hole inthe pump mounting flange, as well as the keyway in thegear.

Hand-tighten the four mounting nuts.

Install the pump driveshaft nut and spring washer.

Torque Value: 36 n•m [ 27 ft-lb ]

Note : Do not overtighten; this is not the final torque.

Tighten the fuel injection pump mounting nuts.




Finishing Steps

Install the injection pump support bracket. Finger-tighten allcapscrews before final tightening.

Tighten the brackets in the following sequence:

1. Bracket-to-fuel pump capscrews2. Brace-to-block capscrews3. Bracket-to-fuel pump brace capscrews.

Tighten all capscrews on the support bracket.

Torque Value: 24 n•m [ 212 in-lb ]Connect the 9-pin connector to the VP44 fuel pump.

Tighten the pump driveshaft retaining nut.


WARNING

Batteries can emit explosive gases. To reduce thepossibility of personal injury, always ventilate thecompartment before servicing the batteries. To reduce the



Last Modified: 06-May-2009

possibility of arcing, remove the negative (-) battery cablefirst and attach the negative (-) battery cable last.

Install the low-pressure fuel lines. Refer to Procedure 006-024 in Section 6 (/qs3/pubsys2/xml/en/procedures/53/53-006-024.html).Install the fuel return lines. Refer to Procedure 006-013 inSection 6. (/qs3/pubsys2/xml/en/procedures/53/53-006-013.html)Install the high-pressure line. Refer to Procedure 006-051in Section 6. (/qs3/pubsys2/xml/en/procedures/53/53-006-051.html)Install the crankcase breather. Refer to Procedure 003-018 in Section 3. (/qs3/pubsys2/xml/en/procedures/53/53-003-018.html)Connect the battery cables, negative (-) cable last.Vent all air from the fuel system. Refer to Procedure 006-003 in Section 6. (/qs3/pubsys2/xml/en/procedures/53/53-006-003.html)Operate the engine and check for leaks.
https://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/53/53-006-024.htmlhttps://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/53/53-006-013.htmlhttps://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/53/53-006-051.htmlhttps://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/53/53-003-018.htmlhttps://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/53/53-006-003.html

warning warning disconnect the vp44 fuel pump drain line … · 2019. 9. 4. · vp44 fuel pump....

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