APPLICATIONS
| Application | Body Type | Carb. No. |
|---|
| 5.0L |
| Auto. Trans. w/o A/C | F | 17085480 |
| Auto. Trans. w/ A/C | F | 17085482 |
| Man. Trans. w/o A/C | F | 17085481 |
| Man. Trans. w/ A/C | F | 17085483 |
| Auto. Trans. (3-Speed) |
| W/o A/C | B, G | 17085484 |
| W/ A/C | B, G | 17085486 |
| Auto. Trans. (4-Speed) |
| W/ A/C | B | 17085494 |
| W/o A/C | B, G | 17085488 |
| W/ A/C | B, G | 17085490 |
| 5.7L |
| Auto. Trans. w/o A/C | B (1) | 17085596 |
| Auto. Trans. w/ A/C | B (1) | 17085598 |
| (1) Police models only. |
SPECIFICATIONS
| Application | Degrees BTDC @ RPM |
|---|
| 5.0L | 4 @ 500 |
| 5.7L |
| Non-Catalyst | 2 @ 600 |
| Catalyst | 6 @ 500 |
IGNITION TIMING SPECIFICATIONS
| Application | RPM |
|---|
| 5.0L |
| Auto Trans | 1850 |
| Man Trans | 1500 |
| 5.7L |
| Non-Catalyst | 1850 |
| Catalyst | 2200 |
FAST IDLE RPM SPECIFICATIONS
| Application | RPM |
|---|
| 5.0L |
| Auto. Trans. (1) | 600-650 |
| Man. Trans. (1) | 750 |
| 5.7L (1) | 650 |
| (1) Idle RPM is with solenoid activated. |
| (1) | Idle RPM is with solenoid activated. |
CURB IDLE RPM SPECIFICATIONS
| Application | RPM |
|---|
| 5.0L |
| "F" Body |
| Auto Trans | 570-610 |
| Man Trans | 730-770 |
| "G" Body | 520-560 |
| 5.7L | 620-650 |
PROPANE ENRICHED RPM SPECIFICATIONS
IDLE MIXTURE CHECK & ADJUSTMENT - PROPANE ENRICHMENT METHOD
Note. Idle mixture screw is preset and sealed at factory. Idle mixture should be adjusted only in case of major carburetor overhaul, throttle body replacement or high emissions as determined by official inspections.
| CAUTION | Adjusting mixture by other than following method may violate provincial laws. Because of sealed idle mixture screw, idle mixture checking procedure requires artificial enrichment by adding propane. |
Installing Propane Idle Enrichment Flowmeter. Scheme 1
Scheme 1: Installing Propane Idle Enrichment Flowmeter
M4ME & M4MC Carburetors
- Set parking brake and block drive wheels. Engine must be at normal operating temperature and A/C off (if equipped). Disconnect and plug hoses as directed on Vehicle Emission Control Information decal under hood.
- Connect an accurate tachometer to engine. Disconnect vacuum advance and set timing to specification indicated on decal. Connect vacuum advance and set carburetor idle speed RPM to specification indicated on decal.
- Disconnect crankcase ventilation tube from air cleaner. Using propane tool (J-26911), insert hose with rubber stopper from propane valve, into crankcase ventilation tube opening in air cleaner. Propane cartridge must be vertical.
- With engine idling in "DRIVE" (auto. trans.) or "NEUTRAL" (man. trans.), slowly open propane control valve while pressing button. Continue to add propane until maximum enriched idle RPM drops due to excessive richness. Note maximum enriched idle RPM.
- If rich RPM drop cannot be obtained, check for empty cartridge or propane system leaks. Propane enrichment RPM is differential between idle speed RPM and maximum idle RPM. Maximum idle RPM is idle RPM plus propane enrichment RPM.
- If maximum enriched idle RPM is within specification, idle mixture is correct. See PROPANE ENRICHED RPM table. If maximum enriched idle RPM is not within specification, remove carburetor from engine to gain access to plug covering idle mixture needle and remove plug.
- Lightly seat mixture needle and then back out 3 turns. Place transmission in "DRIVE" (auto. trans.) or "NEUTRAL" (man. trans.). Back needle out 1/8 turn at a time until maximum idle speed is obtained. Set idle speed to maximum enriched idle RPM.
- Turn mixture needle in 1/8 turn at a time until idle speed reaches value indicated on decal. Recheck maximum enriched RPM with propane. If not within specification, repeat adjustment procedure.
- After adjustments are complete, seal idle mixture needle setting using RTV silicone sealant. The sealer is required to prevent tampering with setting and to prevent possibility of fuel vapors leaking.
- Check fast idle speed. If necessary, adjust fast idle speed as described on decal. Turn off engine. Remove propane tool and connect crankcase ventilation tube. Unplug and reconnect vacuum hoses. Install air cleaner. Remove block from drive wheels.
