12V Fuel Shutoff Solenoid 3921978 for Cummins 6CT 6CTA 8.3L ISC QSC
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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.
| Cummins engines | 6CT, 6CTA, C8.3, ISC, QSC and selected related applications using 3921978 |
|---|
Product Overview
The shutdown solenoid energizes the fuel-control mechanism during operation and returns it to the stop position when power is removed. A failed pull or hold circuit can cause a no-start, immediate stall after key release, intermittent shutdown or an engine that will not stop.
The 3921978 family is widely cross-referenced beyond basic 6CT/6CTA engines, including selected ISC, QSC, ISL and QSL installations. Common interchange numbers include 3918600, 3915502, 3918343 and Case J921978.
Key Features & Performance
- 12V continuous-duty fuel shutdown function
- Primary reference Cummins 3921978
- Broad 8.3L industrial diesel application family
- Common replacement for failed pull/hold shutdown solenoids
Specifications & Reference Numbers
- Voltage: 12V
- References: 3921978, 3918600, 3915502, 3918343, 3921758; Case J921978
- Common configuration: 3-terminal shutdown solenoid
Before You Order
Verify voltage, terminal count, bracket and linkage. Similar Cummins engines can use different solenoid duty cycles and wiring.
Frequently Asked Questions
What should I use as the final fitment check? Use the listed part/reference numbers, your exact engine or machine model, and the physical configuration of the part being replaced. Serial-number and production changes can matter.
What are common reasons to replace this part? The shutdown solenoid energizes the fuel-control mechanism during operation and returns it to the stop position when power is removed. A failed pull or hold circuit can cause a no-start, immediate stall after key release, intermittent shutdown or an engine that will not stop.