Morbark Beever M18R Diesel Catalytic Converter Rebuild
The Morbark Beever M18R is a high-capacity industrial brush chipper designed for demanding land clearing and vegetation management. Diesel-powered M18R machines run a Caterpillar C4.4 Tier 4 Final diesel with DOC/DPF aftertreatment. The stop-start high-load cycle of heavy-duty chipping degrades these systems over time. New England Supply House rebuilds them through our core-exchange program.
Engine & Emissions System
| Engine | Caterpillar C4.4 Tier 4 Final Diesel |
|---|---|
| Emissions Tier | EPA Tier 4 Final |
| Catalyst Type | Diesel oxidation catalyst (DOC) + diesel particulate filter (DPF) |
Why Catalytic Converters Fail on This Machine
Cat C4.4 Tier 4 Final engines use a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) to meet emissions standards. Wood chippers are hard on this system: the stop-start work cycle — chipping a load, shutting down, restarting — prevents the DPF from reaching passive regeneration temperatures. Active regeneration cycles are frequently interrupted when operators don't recognize the warning indicators, and repeated interruptions cause accelerated soot loading. Over time the filter plugs, backpressure rises, and the DOC substrate degrades from thermal stress during forced regen attempts.
What’s Included in the Rebuild
- Full disassembly and inspection of the catalyst housing and substrate
- New catalyst substrate installed to OEM specifications
- Reassembly using your existing housing (core exchange — your housing returns to you)
- Performance verification before return shipping
- Warranty against manufacturing defects
How Core Exchange Works
- Call or submit the fitment check form — we confirm your machine’s engine and emissions configuration before you ship anything.
- Remove your catalytic converter and ship the core to us with tracking and insurance. Ship to: New England Supply House, 14 Pinto Way, Mansfield, MA 02048
- We rebuild and return your core within 3–5 business days.
Request a Fitment Check
Call 774-701-6374 or submit a fitment check request online. This is not a complete list of compatible configurations — call us if your specific engine build isn’t listed.