4996708 - Genuine Cummins Starter 12V for ISB/QSB

Description

Cummins 4996708 Starter 12V - Genuine Cummins Starter for ISB and QSB 6.7L

The Cummins 4996708 is a genuine 12 volt starter for ISB and QSB 6.7L engines. It cranks the engine over to start it, using a plunger type solenoid to throw the 10 tooth pinion into the flywheel ring gear. Built by Denso, 4.8 kW.

Key Functions:

- Cranks the engine for starting
- Plunger type solenoid engages the pinion into the ring gear
- 12 volt, clockwise rotation

Fitment & Specifications:

Cummins ISB and QSB 6.7L
- 12 volt, 4.8 kW, 10 tooth
- Clockwise rotation, 40mm gear OD

Verify fitment with us before ordering to ensure the correct part for your application.

Purpose of the Part

When you turn the key, the solenoid pushes the pinion out to mesh with the ring gear and closes the contacts, sending battery power to the motor to spin the engine over. Once it fires, the pinion kicks back out. Because it pulls heavy current, the starter depends on good batteries, cables and grounds to work right.

Issue Symptoms / When to Replace

No crank or slow crank, a single click when you turn the key, grinding, the starter spinning without engaging, or it staying engaged after start. Heat soak that keeps it from cranking once the engine is hot is another common one.

Before replacing it, check the batteries, cables and grounds, since weak power and bad connections cause the same no crank and slow crank symptoms. Check the ring gear teeth too if you hear grinding.

Brand Information

Cummins sources this starter from Denso, one of the main OE starter manufacturers, so a genuine unit is the same one the engine was built with. It is matched to the 6.7L flywheel and ring gear, so the pinion depth and engagement are right and it holds up to the current draw and heat down by the exhaust. Aftermarket copies often use lighter internals and weaker solenoids, which is where the heat soak no crank and early failures come from.

Installation Notes

1. Disconnect the batteries before touching the starter cables.
2. Check the ring gear teeth for wear or damage while the starter is out.
3. Clean the mounting surface so the starter seats flat and grounds properly.
4. Get the shims right if the old one used them, the wrong pinion depth causes grinding.
5. Torque the mounting bolts and the cable connections to spec, loose cables cause heat and slow crank.
6. Check that the batteries and grounds are good before blaming a new starter for slow crank.

How to Identify an OEM Part

A genuine unit has the Denso name and number stamped on the housing along with the Cummins part number tag. Check they match your order and compare the mounting flange, solenoid and terminal layout to the starter coming off. Copies usually have printed markings and rougher castings.

Why buy from Wisent Parts
  • ⏱️
    Fast shipping
    Orders before 12PM EST ship same business day.
  • 🛡️
    180-day warranty
    All parts covered from delivery date.
  • ↩️
    Easy returns
    30-day returns.
  • ✅
    Verify fitment
    Send VIN/ESN and we’ll confirm.

Shop with confidence

Warranty & Return Information
Warranty Information

Wisent Parts offers a 180-day warranty on all parts from the date of delivery. This warranty covers orders placed directly through our website. If a part fails during this period, we’re here to help - whether it’s a replacement, repair, or refund. For full details, refer to the Warranty page.

Return Information

Wisent Parts accepts returns within 30 days of delivery. All returns are subject to a restocking fee. To qualify, parts must be unused and in their original condition. For full return instructions and restocking fee details, please refer to the Returns page.