Cummins/Onan Onan P4500i / P4500 — High Altitude Kit Installation Procedure

Installation · Carburetor

For the Cummins/Onan Onan P4500i / P4500, from the Cummins/Onan operator's manual.

Applies to: Cummins/Onan Onan P4500i, Cummins/Onan P4500

Procedure

1. Remove battery access panel and disconnect the battery.
2. Remove the maintenance panel on the side by removing the 5 bolts that secure it.
3. Remove the control panel by removing the 4 face screws and the two screws on each side; let it hang loose.
4. Drain all the fuel from the carburetor float bowl into a suitable container.
5. Remove the two bolts that secure the air filter box to the carburetor; remove the lid and foam element.
6. Remove the clamp on the vapor tube; remove the vapor tube and crankcase breather.
7. Remove the two nuts that hold the box base to the carburetor and slide it off.
8. Remove the gasket from the carburetor front face; remove the two electrical connections from the stepper motor.
9. Slide the carburetor off the studs and turn it sideways to remove the fuel line.
10. Remove the bolt at the bottom of the float bowl and remove the float bowl.
11. Using a flat head screwdriver, remove the main jet; the jet and emulsion tube will fall out.
12. Install the emulsion tube back into the carburetor with the ridge on top going in first.
13. Select the appropriate jet for your altitude and install it with a flathead screwdriver.
14. Reinstall the float bowl gasket and the float bowl.
15. Reinstall the carburetor, gasket, air filter box, control panel, and side panel; start and verify operation.

Full service-parts list: Cummins/Onan Onan P4500i →, Cummins/Onan P4500 →

Source: Cummins/Onan operator's 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.

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