Product Description
Cummins 3900068 OEM Ring Dowel (14MM) – Cylinder Head / Main Bearing Cap – 5.9L & 6.7L Cummins
The Cummins 3900068 OEM 14MM Ring Dowel is a genuine Cummins alignment dowel used to properly locate and secure cylinder heads, main bearing caps, and other critical engine components on select 5.9L and 6.7L Cummins diesel engines. Precision-machined to Cummins OEM specifications, the 3900068 ring dowel helps maintain proper component alignment during engine assembly and rebuild procedures.
Whether you're performing a complete engine rebuild, installing a new cylinder head, align boring a block, or servicing the bottom end of your Cummins engine, using genuine Cummins locating dowels helps ensure accurate fitment and long-term reliability. The 3900068 dowel is commonly used throughout B-Series Cummins engine platforms where precise component positioning is critical.
Features
- Genuine Cummins OEM component
- OEM Part Number: 3900068
- 14mm precision alignment ring dowel
- Helps ensure proper cylinder head alignment
- Used for main bearing cap positioning
- Manufactured to Cummins factory specifications
- Supports accurate engine assembly procedures
- Ideal for engine rebuilds and repairs
- Direct replacement for worn or damaged dowels
- Designed for long-term durability and reliability
Fitment
- 1989-2024 Cummins B-Series diesel engines
- 5.9L 12-Valve Cummins engines
- 5.9L 24-Valve Cummins engines
- 5.9L Common Rail Cummins engines
- 6.7L Cummins diesel engines
- Industrial Cummins B-Series applications
- Engine rebuild and machine shop applications
- Cylinder head installation and service
- Main bearing cap installation and alignment
Note: Always verify fitment using your engine serial number (ESN) before ordering. Some applications may require multiple dowels depending on engine configuration and service procedure.
What's Included
- One (1) Genuine Cummins 3900068 OEM Ring Dowel
Specifications
- Manufacturer: Cummins
- Part Number: 3900068
- Product Type: Ring Dowel
- Dowel Diameter: 14mm
- Material: Hardened Steel
- Function: Precision Component Alignment
- Installation Location: Cylinder Head and Main Bearing Cap Applications
- Engine Family: Cummins B-Series
- Application: Engine Assembly and Rebuild
- OEM Replacement: Yes
Cross Reference Numbers
3900068, Cummins 3900068, OEM Cummins Ring Dowel, 14MM Alignment Dowel, Cummins Cylinder Head Dowel, Cummins Main Cap Dowel
FAQ
What is the purpose of the Cummins 3900068 ring dowel?
The 3900068 ring dowel is used to accurately align engine components such as cylinder heads and main bearing caps during assembly. Proper alignment helps ensure correct fitment and long-term engine reliability.
Is this a genuine Cummins part?
Yes. The 3900068 is a genuine Cummins OEM component manufactured to factory specifications.
Will this fit both 5.9L and 6.7L Cummins engines?
Yes. The 3900068 ring dowel is commonly used on various Cummins B-Series 5.9L and 6.7L diesel engine applications. Always verify fitment using your engine serial number.
Should dowels be replaced during an engine rebuild?
Many engine builders replace damaged, worn, or corroded dowels during rebuilds to ensure proper component alignment and assembly accuracy.
How many dowels are required per engine?
The quantity required depends on the specific engine and repair being performed. Consult the Cummins service manual for your application.
Can a damaged dowel cause engine problems?
Yes. Improper component alignment can contribute to sealing issues, assembly problems, and premature wear. Damaged dowels should always be replaced during service.
