Cummins/Onan — Carburetor Disassembly
Repair & overhaul
From a Cummins/Onan service manual covering: 4.5 MCE, 5.0 MCE, 6.5 MCE. Check it applies to your exact model before use.
Applies to: Cummins/Onan 4.5 MCE, Cummins/Onan 5.0 MCE, Cummins/Onan 6.5 MCE, Cummins/Onan MCE engine
Before you start
- Most parts cleaning solutions are flammable.
Procedure
- Disconnect fuel line, governor rod, breather tube, vacuum lines and choke wires.
- Unbolt carburetor from intake manifold.
- Disconnect choke links and remove carburetor adapter.
- Remove throttle and choke plate retaining screws and pull out shafts.
- Remove main and idle mixture screws.
- Separate fuel bowl from upper section.
- Note float assembly positions before sliding out retaining pin.
- Unscrew needle valve seat.
Full service-parts list: Cummins/Onan 4.5 MCE →, Cummins/Onan 5.0 MCE →, Cummins/Onan 6.5 MCE →
Source: Cummins/Onan service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.