Propane Idle Set - Procedure

84chrysler8

Models


1984 MMC Import Vehicles All With Gasoline Fueled Engines, All Emission Markets (Except Vehicles With Turbo Chargers & Canada)


Subject


Propane Idle Set Procedure


Index


FUEL


Date

January 17, 1984


No..


14-08-84

P-94-C

The propane idle set procedure is authorized for 1984 subject model import vehicles.

The propane idle set method is to be used when "CO" meter procedure cannot be used, i.e., "CO" meter in for repair or is not available in the service area.

PROPANE IDLE CHECK & SET PROCEDURE

1. Idle Setting Conditions: Lights, electric cooling fan, and all accessories are off, transmission in neutral, and front wheels in straight ahead position.

2. If engine is cold, allow it to warm up until full operating temperature is reached (185 to 205~F).

NOTE: PERFORM THE FOLLOWING STEPS 3 THROUGH 5 AND STEP 19 ONLY IF ENGINE IS EQUIPPED WITH A FEEDBACK CARBURETOR EMISSION SYSTEM.

3. Turn off ignition switch.

4. Disconnect the NEGATIVE cable from the battery for about 5 seconds. Then reconnect negative battery cable.

5. Disconnect the connector of the exhaust oxygen sensor.

6. Start and run engine for 5 seconds at an engine speed between 2,000 to 3,000 rpm.

7. Then, allow engine to run at curb idle for 2 minutes.

FIGURE 1:

8. Check engine idle speed and basic ignition timing. Adjust to specifications if necessary (Figure 1).
9. Disconnect the air cleaner fresh air intake duct from the air cleaner snorkel.

Insert the propane supply hose into the air cleaner snorkel about 4 inches.

Make certain both valves on propane bottle are fully closed and the bottle is upright and in a safe location.

FIGURE 3:

10. Open the propane bottle main valve fully, then slowly open the propane fine control valve to the position where maximum engine rpm is achieved. (Too much propane or too rich idle mixture will cause the engine to lose rpm as the fine control valve is opened.) (Figure 3.)

FIGURE 2:

Note the engine rpm increase. Specified values of each engine propane idle speed increase are outlined in Figure 2.

If the propane idle speed exceeds more than 25 rpm from the specified value in Figure 2 or the rpm does not increase at all, idle fuel mixture should be adjusted according to the propane assisted idle set procedure that follows.

FIGURE 4:

11. It is not necessary to remove carburetor from intake manifold to remove the idle mixture screw plug.

Drill out concealment plug on car. Remove vacuum connector from high altitude compensator (HAC) fittings on carburetor air horn (Figure 4).

Use a 1/4" diameter drill 8' long at the 11 o'clock position on the plug boss. Locate drill point 3/16" from end of boss.

Plug should pop out when the drill bit contacts it (Figure 4).
12. Start engine and run for 1 minute at engine speed of 2500 rpm.

13. Run engine at idle for 2 minutes.

FIGURE 2:

14. Open the propane main valve and slowly open the fine control valve to the position where maximum engine speed is achieved. Use the idle speed adjusting screw to set the specified propane idle speed from Figure 2.

15. Turn off propane main valve and adjust idle mixture screw to the specified idle set speed from Figure 2.

16. To recheck the maximum propane speed, open the main propane valve again. If the speed still differs more than 25 rpm from the specified propane speed from Figure 2, repeat Steps 14 through 16.
17. Turn off both valves on propane bottle.

18. Remove the propane hose and replace fresh air duct on air cleaner snorkel.

19. Reconnect the exhaust oxygen sensor (if engine is equipped with a feedback carburetor).

20. Install Idle Mixture Screw Concealment Plug. (If new plug is needed, use PN MD606954.)


POLICY: Reimbursable within the provisions of the warranty

FRONT WHEEL DRIVE LABOR OPERATION TIME SCHEDULE:

TIME ALLOWANCE:
Labor Operation No. 14-30-06-93.............. 0.7 Hrs.


FAILURE CODE: RO - Driveability