MTD 643 manual

Snow Thrower Model s 643 & 663 IMPORT ANT : READ SAFETY RULES AND INSTRUCTIONS CA REFULL Y MTD LL C P .O . B O X 36 11 31 CL EVEL AND, OHIO 44 136-0 01 9 Wa rn in g: This uni t is e quip ped wit h an i nter nal com bust ion en gin e and sh ould not be use d on or near an y un impr oved for est- cov e red , bru sh -c overe d or gras s -co ver ed[...]

2 TAB LE O F CON TEN TS Conten t Page Import ant Sa fe Ope ratio n Pract ices ..... ..... .... ... .... ..... ..... .. ..... ..... .... ... ..... .... ..... .. . 3 Assembl ing Yo ur Snow Thrower .... ..... .. ..... ..... .... ... ..... .... ..... ..... .. ..... ..... .... ... .... . 5 Know Yo ur Sno w Thrower .. ..... ..... .. ..... ..... .... ... [...]

3 SECT I ON 1: I M PORT AN T SAF E O PER ATI ON PR AC TICE S This symbol poin ts ou t i m portant safety instructions, which if not followed, co uld endanger the personal safety and/or property of yourse lf an d others. Read and foll ow all i n structions in this manual before attempting to operat e this m achine. Failure to comp ly wi th these ins[...]

4 4. Never oper ate wi th a missi ng or damag ed disch arge chute . Keep al l safety devic es in place and wo rking. 5. Never ru n an engi ne indoo rs or in a poorly ventila ted area. Engine exhaust contains ca rbo n monoxide , an odorl ess and d eadly ga s. 6. Do not ope rate mach ine whi le under t he inf luence of alcoh ol or drugs. 7. Muffle r [...]

5 SECTION 2: ASSEMBLING YOUR SNOW THROWE R NOTE: References to right or l eft side of the snow thrower are determined from behind the unit i n the operating position. The “operator’s position” is defined as standing directly behind the s now thrower, facing the handle panel. Un packing • Remove s crews from the top sides and en ds of the sh[...]

6 SECTION 3: KNOW YOUR S NOW THROWER Fi gur e 5 WARNING: Read , understand, and follow all in structio ns and w ar nings on the ma chi ne an d i n th is man ual bef ore oper ating. T ractio n Control / Au ger Con trol Lock The traction control is locate d on the right handle. Squeeze the traction control to engage the wheel d rive. Release to stop.[...]

7 Headlight The headlight is on whe never the engine is running. Throttle C ontrol The throttle control is located on the engine . I t regulates the speed of the eng ine and will shut off the engine when pushe d down completely. See F igure 5. Clean -Ou t T o ol The chute clean -out tool is fastened to the top of the auger housing with a mou nting [...]

8 Recoil Starte r • Rotate choke kno b to FULL chok e position (cold engine sta rt). I f engine is warm, place choke i n OFF positio n instead of FULL. • Push primer button t wo or three times. If engine is warm, pus h primer b utton once only . NOTE: A lways cover vent hol e in pri mer button whe n pushing. Additiona l priming may be necess ar[...]

9 Fi gur e 6 Chut e Clean- Out T ool The chut e clean-out tool is convenient ly fastened t o the rear of the auger hous ing with a mounting clip. Should snow and ice lodge its elf i n the discharge chute during operation, proceed as fo llows to safely clean the chute and chute openi ng: • Release both the A uger Control Lever an d the T r act ion[...]

10 SECTION 5: MAKING ADJUSTMENTS WARNING: N EVER a t temp t to make any adjustmen ts while the engin e is running, except whe re specified in the operato r ’ s manual . Ti re P res s u re (Pne u matic Tires) • The tires are overinflated for shippin g purposes. Before operat ing check tire pressure and reduc e pressure to bet ween 15psi and 20 p[...]

11 Shift Rod A djustment To adjust the shift rod, proceed as fo llows: • Remove th e hairpin clip and slide the shift rod conn ector up, to separate the upper shift rod from the lower shift rod. See F igure 10. Figu re 10 • Place the shift lever into the sixth (6) position. • Rotate the shift arm clockwise (from t he operator ’ s position) [...]

12 wheel hub.This position gives p ower drive to the left wheel only, ma king the unit easier to maneu ver. Both Whe els Drivin g • Rotate whee l assembly to alig n hole in t he hub wi th the inner hole on the ax le shaft. Insert klick pin in the hol e. Outer axle shaft hole should be v isible. IMPORT ANT: NEVER o perate the snow thrower with the[...]

13 Tractio n Control / Auge r Co ntrol Lock The cams on th e ends of the control rods which interlock the traction drive and aug er d rive controls must be lubricated at least once a season or every 2 5 hours of o peration. T he cams can be accessed benea th the handle panel. Use a multi-purpose auto motive grease. Drive and Shifting M echanis m Lu[...]

14 • Drain the gasoline from the s now thrower, or place a piece of pl astic film under the gas cap. • Tip the snow thrower up and f orward s o that i t rests on its auge r housing. • Remove th e six self-tapping screws from the frame cover unde rneath the snow thrower. • Roll the front and rear auger bel ts of f th e auger drive p ulley. S[...]

15 Figu re 20 • Remove th e four screws from the friction wheel assem bly. Remove the friction wheel rubber from betwee n the friction wheel plates. See Fi gure 21. • Reassem ble the new friction wheel rubber to the friction wheel p lates and hub, tighten ing the six screws in rotation and with equal force. • Position the f riction wheel ass [...]

16 SECTION 8: TROUBLE SHOOTING NOTE: For repairs beyond the mi nor adjustments abo ve, contact your local autho r i zed service dealer. T rouble Possible Cau se( s) Co rrec tive Act ion Engine f ails t o star t Fuel ta nk empty, or st ale fuel . Blocked fuel li ne. Choke not in O N positi on Faulty spark p lug. Key not i n swit ch on engine . Spark[...]

17 2 12 4 6 7 10 9 14 11 8 16 1 3 15 Models 643 & 663 5 13 3 17 Ref. No. P ar t No. Part Description 1. 618-01 23 RH Housing 2. 618-01 24 LH Housing 3. 71 0-0642 Self T apping Scre w , 1/ 4-20 x .75 4. 711-09 10A Spir al Ax le, 28 ” 5. 714-01 61 Hi-Pr o Ke y , 3/16 x 5/ 8 6. 715-01 43 Spring Spi ral Pin, .25 x 1.2 5 7. 71 7-0528 W orm Gear , [...]

18 Models 643 & 663 14 10 2 14 12 16 3 20 60 63 67 65 55 54 8 17 11 22 21 18 4 1 11 15 19 7 14 53 59 68 69 69 27 82 70 72 72 73 27 68 71 74 27 56 64 76 77 78 79 11 15 75 81 27 83 80 13 13 42 26 26 48 9 9 49 23 28 14 28 9 41 39 12 43 43 10 26 31 35 38 40 6 6 5 5 24 24 30 32[...]

19 Models 643 & 663 Ref. No. Part No . Part Descri pti o n 1. 684-0 008A Shift Ar m Assem bly 2. 710-0 458 Carri age Bolt 5/ 16-18 x 1.75 ” 3. 710-0 449 Carri age Bolt 5/ 16-18 x 2.25 ” 4. 710-0 788 TT Screw 1 /4-20 x 1 ” 5. 712-0 429 Hex L ock Nut 5/16 -18 6. 746-0 778 Z Fit ting Ca ble 7. 710-1 880 Hex S crew 5/16-18 x .75 ” 8. 711-0 [...]

20 Mode ls 643 & 663 1 2 3 4 5 6 7 8 9 10 11 12 14 15 13 16 10 26 18 27 28 13 30 31 32 33 16 18 35 34 36 37 38 39 41 40 42 17 40 39 29 24 9 19 30 31 50 51 52 49 48 47 43 44[...]

21 Mode ls 643 & 663 Ref. No. P ar t No. P art Descr iption 1. 712-0116 L ock Jam Nut 3/ 8-24 2. 756-0178 F lat I dler 3. 784- 5632B Auger Idler Ar m 4. 710-0459A He x Cap Scr e w 3/8-24 x 1.50 5. 738-0281 Sh oulder Screw 6. 736-0167 W ave Washer 7. 732-0611 Ex tensi on Spring 8. 712-3068 He x Nut 5/ 16-18 9. 710-0276 Ca rria ge Bolt, 5/ 16-18 [...]

22 Mode ls 643 & 663 1 2 3 4 5 6 7 4 8 9 10 11 12 13 14 15 16 17 18 19 19 16 16 16 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 IMPORTANT: For a prop er working machi ne, use Facto ry Approved Par ts. V-BELTS are spec iall y designed to engage an d dis engage safel y. A substitu te ( non OEM) V -Belt can be danger ous by not di sengagi ng co[...]

23 Mode ls 643 & 663 Ref. No. P art No. Part Description 1. 710- 1652 Hex Was her Screw 1/4 -20 x . 625 2. 731- 1324 Belt Co ver 3. 732- 0710 Extensi on Spring 4. 710- 0627 Hex Screw 5/16-24 x .75 5. 710- 3005 Hex Cap Scr ew 3/8-1 6 x 1.25 6. 0589 6A Dr ive Clutch Idler Br acket 7. 748- 0234 Shoulder Spacer 8. 756- 0987 Pulle y Half 9. 754-0346[...]

24 Models 643 & 663 1 1 2 3 4 4 5 5 6 16 ” W heel s 13 ” or 15 ” Whee ls 4 7 7 8 9 10 10 11 11 12 41 5 13 14 15 16 17 18 1 19 20 21 22 23 24 25 25 26 28 29 1 1 30 31 32 33 34 8 35 Dri ve Cl utch Cable Au ge r Cl ut ch Cable Auger Clutch Cable Blo wer Housi ng 36 20 37 38 39 40 27 42 42 42 43 44 45 46[...]

25 Mode ls 643 & 663 Ref. No. P a rt No. P a rt Description 1. 710-0599 Hex Scr ew 2. 784-5688 Driv e Cabl e Guide Bra ck et 3. 784-5687A Auger C lut ch Cabl e B rac ket 4. 756-0625 Roller C ab le 5. 738-0924 Hex Scr ew 1/4- 28 6. 784-5630B F rame Ass emb ly 7. 741-0563 Ball Bearing 8. 736-0105 Bell W ash er 9. 712-0116 Loc k Jam Nut 10. 741-05[...]

26 Notes[...]

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MANUF A C TURER ’ S LIMITED W ARRANTY FOR: The l imited w arran ty set f or th belo w is giv en by MTD LLC wi th respec t to new merc handise purcha sed and used in th e Unit ed Stat es, its po ssessions and te rritories. MTD LLC warrant s thi s product ag ainst def ects f or a peri od of two (2) year s com m e ncing on the date of original purch[...]