Here are the diagrams and repair parts for Official MTD 138-668-088 lawn tractor, as well as links to manuals and error code tables, if available.
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Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.
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Single speed transaxle right hand diagram
Part #736-0188
Part #710-0837
Single speed transaxle right hand diagram
Part #710-0809
Choose a symptom to see related riding mower and lawn tractor repairs.
Main causes: unlevel mower deck, dull or damaged cutting blades, worn mandrel pulleys, bent mower deck, engine needs tun…
Main causes: dead battery, stale fuel, bad starter solenoid, ignition system problem, bad ignition interlock switch, clo…
Main causes: damaged tie rods, bent or worn wheel spindle, worn front axle, damaged sector gear assembly…
Main causes: punctured tire or inner tube, leaky valve stem, damaged wheel rim…
Main causes: worn or broken blade belt, broken belt idler pulley, blade clutch cable failure, bad PTO switch, damaged ma…
Main causes: faulty battery, bad alternator…
Main causes: damaged cutting blade, worn deck pulley, damaged mandrel pulley, loose fasteners on mower deck components…
Main causes: shift lever needs adjustment, neutral control needs adjustment…
Main causes: worn or broken ground drive belt, bad seat switch, transaxle freewheel control engaged, transaxle failure, …
These step-by-step repair guides will help you safely fix what’s broken on your riding mower or lawn tractor.
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Use the advice and tips in these articles and videos to get the most out of your riding mower or lawn tractor.
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Check the starter solenoid, starter motor, wiring, battery and engine.…
You might find the answers to your questions about your riding mower or lawn tractor in this list of frequently asked qu…