FUEL SYSTEMS MERCARB 2 BARREL CARBURETOR 5 B

Transcription

1 FUEL SYSTEMS MERCARB 2 BARREL CARBURETOR 5 B

2 Tle of Contents Pge MerCr 2 BBL Cruretor B-1 Torque Specifictions B-1 Tools B-1 Specifictions B-1 Identifiction B-2 Exploded View B-3 Adjustments B-4 Choke Setting B-4 Checking Flot Weight B-4 Pump Rod B-4 Flot Level B-5 Flot Drop B-6 Preliminry Idle Speed nd Mixture.... 5B-6 Finl Adjustments B-7 5B-0 - MERCARB BARREL CARBURETOR

3 MerCr 2 BBL Cruretor Torque Specifictions Units of Mesurements In. (mm) Fstener Loction l. ft. (N m) Cruretor To Mnifold 20(27) Fuel Line to Cruretor 18(24) Fuel Inlet Filter Nut 18(24) Tools Prt Numer Description A1 Tchometer Universl Cruretor Guge Boroughs Specil Tool nd Equipment Inc N. Burdick Street Klmzoo,MI (616) BT 8128 B Specifictions Flot Grm Scle Engine Model 3.0L 3.0LX 4.3L 5.0L Cruretor Type MerCr MerCr 43mm MerCr 35mm MerCr 35mm 36mm/43mm Cruretor Numer / A Flot Level 2 Piece Solid Inlet Needle Spring Loded Needle 3/8 (10) See Note 1 9/16 (14) See Note 1 Flot Drop 1-3/32 (27) (See Note 1) Pump Rod 1-5/32 (29) Choke Setting Index Mrks Aligned Choke Unloder 5/64. [080] (2) Idle Mixture Screws 1-1/4 Turns Flot Weight 9 Grms Mx. Primry Jet Size 1.45 mm/1.60 mm 1.65 mm 1.60 mm 1.85 mm Power Vlve Size 0.84 mm/0.74mm 0.74 mm 1.78 mm 1.0 mm Venturi Cluster I.D. 442/ Numer Accelertor Pump Dischrge Hole Size.025 (0.635).035 (0.889) Note: 1 Mesurement tken from gsket MERCARB 2 BARREL CARBURETOR - 5B-1

4 Identifiction Cruretor Prt Numer Loction - Prt Numer - Dte Code Dt Code Explntion: Exmple 2301 First Figure is Yer: 2 = 1992, 3 = 1993, etc. Second Figure is Month: 2 = Ferury, 3 = Mrch, etc. X = Octoer, Y = Novemer, Z = Decemer Third nd Fourth Figures re Dy of Month: 01 = First dy, 02 = Second dy, etc Identifiction Numer (See Specifictions) Venturi Cluster Identifiction 5B-2 - MERCARB 2 BARREL CARBURETOR

5 Exploded View 1 - Air Horn 2 - Gsket 3 - Screw 4 - Screw 5 - Lockwsher 6 - Nut - Fuel Inlet 7 - Gsket 8 - Gsket 9 - Spring 10 - Filter 11 - Inlet Needle nd Set (Solid) 12 - Bffle Plte 13 - Pin 14 - Flot 15 - Flot Bowl 16 - Venturi Cluster 17 - Gsket 18 - Screw 19 - Screw 20 - Lockwsher 21 - Flt Wsher 22 - Gsket 23 - Power Vlve Assemly 24 - Gsket 25 - Jet 26 - Gsket 27 - Pump Shft nd Lever Assemly 28 - Screw 29 - Wsher 30 - Clip - Retiner 31 - Accelertor Pump Assemly 32 - Spring 33 - Nut 34 - Spring Wsher 35 - Inlet Needle nd Set (Spring Loded - Optionl) 36 - Cm - Idle 37 - Screw 38 - Throttle Body 39 - Gsket 40 - Idle Mixture Adjusting Needle 41 - Spring 42 - Screw - Idle Speed Adjustment 43 - Spring 44 - Screw 45 - Lockwsher 46 - Choke/Housing 47 - Gsket 48 - Screw 49 - Lever Assemly 50 - Screw 51 - Rod - Choke 52 - Rod - Accelertor Pump 53 - Accelertor Pump Shft nd Lever Assemly 54 - Wsher (Outer) 55 - Wsher (Inner) 56 - Throttle Lever 57 - Nut 58 - Wsher - Locking 59 - Clip - Pump Rod 60 - Retiner 61 - Spring 62 - Check Bll MERCARB 2 BARREL CARBURETOR - 5B-3

6 Adjustments! WARNING Checking Flot Weight Avoid gsoline fire or explosion. Improper instlltion of rss fittings or plugs into fuel pump or fuel filter se cn crck csting nd/or cuse fuel lek. Apply #592 Loctite Pipe Selnt with Teflon to threds of rss fitting or plug. DO NOT USE TEF-LON TAPE. Thred rss fitting or plug into fuel pump or fuel filter se until finger tight. Tighten fitting or plug n dditionl 1-3/4 to 2-1/4 turns using wrench. DO NOT OVER- TIGHTEN. Instll fuel line. To prevent over-tightening, hold rss fitting with suitle wrench nd tighten fuel line connectors securely. Check for fuel leks. -Grms Scle -Flot Choke Setting Norml choke setting is such tht scried mrk on cover is in line with long cse mrk on choke housing. Pump Rod 1. Bck out idle speed screw until it no longer contcts idle cm. c Ilde Speed Screw - Ilde Cm - Scried Mrk - Lener c - Richer 5B-4 - MERCARB 2 BARREL CARBURETOR

7 2. With throttle vlves completely closed, mesure from flme rrestor mounting surfce to top of pump rod. Flot Level 1. Turn ir horn upside down. Pivot flot ssemly up nd down on hinge pin to ensure it moves freely. IMPORTANT: Before checking flot level, rise flot nd llow it to fll; however, DO NOT force downwrd y hnd. 2. Mesure flot level using Universl Cruretor Guge (P/N ). Mesure from gsket to toe of flot. - Mesurement 1-5/32 in. (29 mm) 3. Bend s shown Mesurement from this Point to Gsket Pump Rod - Bend Here For Correct Adjustment - Mesurement With 2 Piece Solid Inlet Needle - 3/8 in. (10... mm)mesurement With Spring Loded Inlet Needle - 9/16... in. (14 mm) 3. Bend flot rm shown MERCARB 2 BARREL CARBURETOR - 5B-5

8 Preliminry Idle Speed nd Mixture 1. Bck out idle speed screw until it no longer contcts idle cm. Turn idle speed screw in until it just contcts idle cm, then turn screw in n dditionl two turns Bend Flot Arm t This Point For Correct Adjustment 4. Visully check flot lignment fter djustment. Flot Drop - Idle Speed Screw - Idle Cm IMPORTANT: DO NOT turn idle mixture needle tightly ginst set (in the following step), s dmge to set nd/or needle my result. 2. Turn idle mixture needle in until lightly seted, then ck needle out 1-1/4 turns Idle Mixture Needle - Mesurement - 1-3/32 in. (27 mm) From Gsket To Toe Of Flot 5B-6 - MERCARB 2 BARREL CARBURETOR

9 Finl Adjustments IMPORTANT: Bot MUST BE in the wter nd engine t norml operting temperture to ccurtely check nd djust idle speed nd mixture. Cruretor should e set so tht engine idles s smoothly s possile, with ot in the wter, engine norml operting temperture nd drive unit in forwrd ger. To djust idle speed nd mixture, proceed s follows: IMPORTANT: DO NOT ttempt to compenste for other engine prolems ( incorrect ignition timing, fulty ignition components, low compression, vcuum leks, etc.) with cruretor djustments. This will only cover the prolem, which must e corrected if engine is to chieve mximum fuel economy nd performnce. 1. Connect shop tchometer to engine. 2. Strt engine nd run t 1500 RPM until engine reches norml operting temperture.! WARNING DO NOT leve helm unttended while performing idle speed nd mixture djustments, following. BE CAREFUL NOT TO ACCIDENTALLY ACCELERATE ENGINE WHILE PERFORMING ADJUSTMENTS. 3. With ot in open wter, plce remote control in forwrd ger, idle position. ADJUSTING IDLE MIXTURE SCREW To djust the idle screw correctly, the throttle pltes must e just out closed. To mke sure this is done do the following: 4. Disconnect the throttle cle 5. Reset idle speed (RPM) screw so engine idles t RPM in neutrl ger 6. Adjust idle mixture screw 7. Reset idle speed screw until engine idles t RPM in forwrd ger. 8. Adjust nd connect throttle cle FLOODING AT IDLE RPM If engine is flooding t idle RPM, check the following: 1. Ignition system prolem cusing engine to run rough 2. Idle mixture screw djusted incorrectly 3. Bd needle nd set 4. Incorrect flot level or flot drop MERCARB 2 BARREL CARBURETOR - 5B-7