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SKU:
NLT1E02250
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Cummins Mechanical Fuel Transfer Pump 3936317 3921550
$76.99
In Stock
$76.99
Sale price
$76.99
Regular price
This new aftermarket mechanical piston-style fuel transfer pump replaces Cummins 3936317, 3921550, J936317, and related references for compatible 4B, 4BT, 6B, 6BT, 6CT, B3.9L, and B5.9L diesel engines with inline injection-pump applications.
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
Compatible equipment / model
- Cummins 4B and 4BT engine applications with matching mechanical pump
- Cummins 6B and 6BT / B5.9L 12-valve applications using an inline injection pump
- Cummins 6CT and selected C-Series applications with the listed pump
- Cummins B3.9L 8-valve applications using 3936317
- Industrial and equipment installations must be verified by engine serial and pump layout
Product Overview
Long cranking, low supply pressure, loss of power, or a filter that will not stay full can indicate a weak transfer pump after tank pickup, vent, lines, filter, air leaks, and shutdown controls are checked. Diesel leakage into the engine oil requires immediate attention.
The engine-driven pump pulls fuel from the tank and supplies the injection pump at low pressure. It is not an electric lift pump and does not replace the high-pressure injection pump.
Match the injection-pump family, mounting flange, operating tappet or plunger, 1/4-18 NPTF inlet where applicable, outlet orientation, priming lever, engine CPL / serial, and original references.
Key Features & Performance
- Mechanical piston-style low-pressure fuel pump
- Engine-driven operation without a separate electric motor
- Manual priming lever on compatible configurations
- Multiple Cummins supersession and cross-reference numbers
Replaces Part Numbers
- 3936317
- J936317
- 3921550
- 3917334
- 3925856
- 3926034
- 3930135
- 3932225
- 3933253
Common Uses
- Restoring fuel supply to a mechanical injection pump
- Replacing a transfer pump that leaks externally
- Correcting confirmed low supply pressure under load
Technical Specifications
- Product Type: Mechanical diesel fuel transfer pump
- Pump Style: Engine-driven piston type
- Engine Families: Compatible Cummins B and C applications
- Condition: New aftermarket replacement
Installation & Fitment
- Clean the engine and close the fuel supply
- Compare actuator and port positions
- Use the correct gasket and avoid excess sealant
- Prime the system with the lever where provided
- Start the engine and test supply pressure and leaks
Compatibility Notice
Northline Parts does its best to list all known compatible models, but the correct part may fit an application that is not shown above. Model year, production date, serial number, engine or equipment specification, installed options, and previous repairs can change fitment. Match the original part, reference number, dimensions, connectors, mounting points, and product photos before purchase.
Frequently Asked Questions
Q: Is this an electric pump? A: No. It is an engine-driven mechanical transfer pump.
Q: Can it fix low power on a 6BT? A: Only if testing confirms inadequate supply pressure from this pump. Filters, air leaks, tank pickup, injectors, and the injection pump also matter.
Q: Will it fit every Cummins 6BT? A: No. Match engine serial / CPL, injection-pump type, flange, actuator, and ports.
Q: Is this an original-equipment part? A: No. This is a new aftermarket product. Brand names and part numbers are used only to identify compatible applications.
Part Summary
keywords: Cummins 3936317 transfer pump, 3921550 mechanical lift pump, 6BT low fuel pressure repair, 4BT fuel filter loses prime, J936317 piston pump replacement
Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, specifications, and application before purchase.