Operator's Manual 21" Self-Propelled Lawn Mower Model 378Q \ IMPORTANT: Read safety rules and instructions carefully Warning: This unit is equipped with an internal combustion engine and should not be used on or near any unimproved forest-covered, brush-covered or grass-covered land unless the engine's exhaust system is equipped with a spark arrester meeting applicable local or state laws (if any). If a spark arrester is used, it should be maintained in effective working order by the operator.
TABLEOFCONTENTS Content Important SafeOperation Practices SlopeGauge Assembling YourLawnMower KnowYourLawnMower Operating YourLawnMower Page 3 6 7 8 Content Making Adjustments Maintaining Your Lawn Mower Troubleshooting Illustrated Parts List Page 11 12 14 15 9 Warranty 20 FINDINGMODELNUMBER This Operator's Manual is an important part of your new lawn mower. It will help you assemble, prepare and maintain the unit for best performance. Please read and understand what it says.
SECTION1: IMPORTANT SAFEOPERATION PRACTICES WARNING" This symbol points out important safety instructions which, if not followed, could endanger the personal safety and/or property of yourself and others. Read and follow all instructions in this manual before attempting to operate this machine. Failure to comply with these instructions may result in personal injury. When you see this symbol--HEED ITS WARNING.
unclogging thechute. Thecutting bladecontinues to Keep children away from hot or running engines. They can suffer burns from a hot muffler. rotate forafewseconds aftertheengine isshutoff. 6. Never placeanypartofthebodyinthebladeareauntil Never allow children under 14 years old to operate a youaresurethebladehasstopped rotating. power mower. Children 14 years old and over should 13.
3. Check thebladeandengine mounting boltsatfrequent intervals forproper tightness. Also,visually inspect blade fordamage (e.g.,bent,cracked, worn)Replace blade withtheoriginal equipment manufacture's (O.E.M.) blade only,listedinthismanual. "Useofpartswhichdonot meettheoriginal equipment specifications mayleadto improper performance andcompromise safety!" 4. Mower blades aresharpandcancut.Wrapthebladeor weargloves, anduseextracaution whenservicing them. 5.
I o E II 91 SIGHT AND HOLD THIS LEVEL WITH A VERTICAL TREE t- 191 I -. ,. I A POWER POLE A CORNER OF A BUILDING I ill O " .. ,_ 4) III! !11 II1 I ,II I OR A FENCE POST I 4) ~ ~ ~FQLDo^. O .._"- iO I::l d) o *d r- t.O E o rd) o 15 ° o ,_ o) cu 05 o WARNING Do not mow on inclines with a slope in excess of 15 degrees (a rise of approximately 2-1/2 feet every 10 feet). A riding mower could overturn and cause serious injury.
SECTION3: ASSEMBLING YOURLAWNMOWER RemovingUnitFromCarton • • • • Remove staples, break glue on top flaps, or cut tape at carton end and peel along top flap to open. Remove loose parts if included with unit (i.e., operator's manual, grass bag etc.) Cut along corners, lay carton down flat, and remove packing material and bottle of oil, if any. Roll or slide unit out of carton and check carton Tighten these wing nuts \ thoroughly for loose parts.
• • • Loosen the wing nut holding the rope guide to the upper handle. See Figure 6. Squeeze the blade control handle against the upper handle and pull starter rope out slowly. Thread the recoil starter rope into the rope guide and tighten the wing nut. Starter Rope \ Upper Handle Nut IMPORTANT: This unit is shipped without gasoline or oil in the engine.
SECTION5: OPERATING YOURLAWNMOWER NOTE: For shipping purposes your mower is set with the wheels in a low cutting height position. For best results raise the cutting position until it is determined which height is best for your lawn. See the adjustment section for details. WARNING: operator is standing near the lawn mower while starting engine or operating mower. WARNING: Never run engine indoors or in enclosed, poorly ventilated areas. Engine exhaust contains carbon monoxide, an odorless and deadly gas.
Fora healthierlawn,nevercutoffmorethanonethirdofthetotallengthofthegrass.Yourlawn shouldbecutinthefallaslongasthereis growth. Thismowerisdesignedtobeoperatedatfull throttletogiveyouthebestcutanddothemost effective jobofmowingor mulching. ,i_ AttachingGrassBag • • Lift the rear discharge door and remove the mulching plug, if installed. Lift the rear discharge door and hang the grass bag on the mower. See Figure 10. WARNING" the mower strikeswire a foreign object, stop the Ifengine.
SECTION6: MAKINGADJUSTMENTS ,_ Reassemble the upper handle to the lower handle. Attach the starter rope as instructed in the Assembly Section. adjustments without engineany and WARNING: Do notfirst at stopping any time make disconnecting spark plug wire. \ CuttingHeight • The cutting height adjustment lever is located above the left rear wheel. Pull the lever out and away from the mower and then move it forward or back for a new cutting height. See Figure 12.
SECTION7: MAINTAININGYOURLAWNMOWER GeneralRecommendations Cleaningthe Deck • Always observe safety rules when performing any maintenance. IMPORTANT:We do not recommend the use of a • The warranty on this lawn mower does not cover items that have been subjected to operator abuse or negligence. To receive full value from the warranty, the operator must maintain the lawn mower as instructed in this manual. • Some adjustments will have to be made periodically to maintain your unit properly.
• • • • • • • Test the blade by balancing it on a round shaft screwdriver. Remove metal from the heavy side until it balances evenly. It is recommended that the blade always be removed from the adapter when testing for balance. Before reinstalling the blade and the blade adapter to the unit, lubricate the engine crankshaft and the inner surface of the blade adapter with light oil. Be sure to install the blade with the side marked • • • Tip the mower back on its handle and block securely.
wayfortheselfpropelledmechanism towork. Checktheinstallation ofthegearbyspinningthe wheel.It shouldspinfreelyinonedirectionbutnot theother.If thewheelspinsfreelyinboth directions, flipthegearover. Tipthemowerbackontoitswheelsandperformthe neutraladjustment testdescribed onpage9. • • • Clean and lubricate mower thoroughly as described in the lubrication instructions. Follow the engine manual for engine storage. Coat mower's cutting blade with chassis grease to prevent rusting.
SECTION9: PARTSLISTFORMODEL378 37 36 \\\ 16 38 R\\\\\\\\\ _* 36 22 44 8 0 R\\\\ 39 42 34\ 32 26 7 33 3Q 18 40 13 Ref. No. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. Part No.
Model378 2 \ 1 ,/ 14 18 \\ 19 \ 31\ 32 35 36 52 39 16
Model378Q Ref. No. Pa_No. Description 1. 710-1667 Hi-Lo Screw 2. 731-1058 3. 731-0620 Control Housing: Lower Drive Control Lever 4. 731-1057 Control Housing: Upper 5. 731-1059 Mounting Cap: SP Cable 6. 710-1205 7. 720-0279 Eye Bolt Handle Knob 8. 749-0439B Upper Handle Hex Lock Nut 1/4-20 9. 712-0324 10. 746-0875 11. 710-0605 12. 736-0501 13. 746-0876 14. 710-1174 15. 736-0451 16. 720-0284 17. 749-0907B Knob Assembly Lower Handle 18.
Model378 _._ 2 2 4 12 13 15 \\\ 29 14 _27 \\ J _30 25 28 _\\\\ 23 _33 \\\ 16 \\\\ 17 22 20 21 18
Model378 Ref. Part No. Description 712-3025 Hex Jam Nut 5/16-24 736-0425 Bell Washer 756-0656 736-3084 Pulley Flat washer 712-0896 Hex Jam Nut 782-7598 Belt Keeper 741-0124 Bearing 7501050 Flange Spacer 682-0027A Idler Bracket Assembly 710-0299 Hex Cap Screw Torsion Spring No. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34.
MANUFACTURER'S LIMITED WARRANTY The limited warranty set forth below is given by MTD LLC with respect to new merchandise purchased and used in the United States, its possessions and territories. e, "MTD"warrants this product against defects in material and workmanship for a period of two (2) years commencing on the date of original purchase and wilt, at its option, repair or replace, free of charge, any part found to be defective in materials or workmanship.
