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Bolens 660 THRU 688 lawn tractor

Bolens 660 THRU 688 lawn tractor Parts

Here are the diagrams and repair parts for Bolens 660 THRU 688 lawn tractor, as well as links to manuals and error code tables, if available.

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Browse Parts for 660 THRU 688 Riding Mowers & Tractors

  • Deck Assembly, 38-in for Bolens 660 THRU 688 - Part 683-04003A

    Deck/blade diagram

    Deck Assembly, 38-in

    Part #683-04003A

    The manufacturer no longer makes this part, and there's no substitute part

  • Dash Panel for Bolens 660 THRU 688 - Part 731-04179

    Dash Panel

    Part #731-04179

    The manufacturer no longer makes this part, and there's no substitute part

  • Shift Hex Grip for Bolens 660 THRU 688 - Part 720-04008

    Lift handle/lift shaft/frame diagram

    Shift Hex Grip

    Part #720-04008

    The manufacturer no longer makes this part, and there's no substitute part

  • Panel for Bolens 660 THRU 688 - Part 783-04031

    Lift handle/lift shaft/frame diagram

    Panel

    Part #783-04031

    The manufacturer no longer makes this part, and there's no substitute part

  • Pipe Nipple for Bolens 660 THRU 688 - Part 737-0199

    Engine/muffler/deck diagram

    Pipe Nipple

    Part #737-0199

    The manufacturer no longer makes this part, and there's no substitute part

  • Grease for Bolens 660 THRU 688 - Part 737-0148

    Upper and lower housing diagram

    Grease

    Part #737-0148

    The manufacturer no longer makes this part, and there's no substitute part

Bolens Lawn Tractor 660 THRU 688 FAQs

To start your Bolens 660 front-engine lawn tractor, we set the parking brake, make sure the PTO (blade) switch is off, sit in the seat, and then turn the key to crank the engine. Most no-start issues come from safety interlocks, fuel, or a weak battery; check the owner's manual for your exact control locations.

Quick start steps (most Bolens riding mowers)

  • Sit fully on the seat (seat switch must be engaged).
  • Move the PTO or blade lever/switch to OFF.
  • Set the parking brake; on many tractors this means pressing the clutch or brake pedal fully and latching the brake.
  • Put the transmission in neutral (or make sure the shifter is in the neutral slot).
  • Move the throttle to FAST; use CHOKE if the engine is cold.
  • Turn the key to START; release it as soon as the engine fires.

If it will not crank (no spin)

These checks solve most “turn key and nothing happens” problems:

  • Confirm the brake pedal is fully depressed and the parking brake is set.
  • Verify the PTO is off; the tractor will not crank with blades engaged.
  • Check battery cables for tight, clean connections.
  • Listen for a click at the starter solenoid; clicking often points to low battery voltage.
  • Inspect the seat switch and brake switch for loose connectors.

Helpful walkthrough: riding lawn mower engine wont turn over or click video

If it cranks but will not start

Focus on fuel and ignition basics:

  • Make sure there is fresh fuel and the fuel shutoff (if equipped) is open.
  • Set choke correctly (more choke cold, less choke warm).
  • Check the air filter for heavy dirt or oil saturation.
  • If it starts then dies when you release the brake, recheck the brake switch and interlock circuit.

Helpful walkthrough: riding lawn mower engine spins but wont start video

Common control positions (what to look for)

Control Typical “start” position What it prevents if wrong
Parking brake / brake pedal Fully set / fully depressed No crank
PTO (blade) switch/lever OFF / disengaged No crank
Throttle FAST Hard starting / stalling
Choke ON for cold start Flooding if left on warm

Why it matters

Your Bolens 660 uses safety interlock switches (seat, brake, PTO) to prevent starting or running in unsafe conditions. Starting steps that seem minor, like fully setting the brake or turning the PTO off, directly control those switches.

Last updated: February 2026

A lawn mower or lawn tractor is made up of several major systems: the engine (fuel, air, ignition, exhaust), the drive and cutting systems, steering and braking, and safety controls. For your Bolens 660 lawn tractor, the exact part list and diagrams are in the Bolens 660 owner's manual.

Main part groups you will see

Most riding mowers and tractors (including Bolens models) are organized into these common assemblies:

  • Engine and fuel: fuel tank, fuel lines, carburetor, choke/throttle linkages
  • Air intake and ignition: air filter, spark plug, ignition coil, flywheel
  • Exhaust: muffler, exhaust gasket, mounting hardware
  • Lubrication: oil fill, drain, dipstick, seals
  • Drive system: belts, pulleys, transmission, idlers
  • Cutting deck: blades, spindles, deck belt, deck lift linkage
  • Steering and front axle: steering wheel, steering shaft, pivot bar, axle assembly, bearings
  • Brakes and safety: brake linkage, puck brake, seat switch, interlock switches

Examples of real replacement parts for Bolens 660

These are examples of parts commonly replaced during repairs and maintenance:

  • Exhaust sealing: gasket 692236
  • Steering wear items: steering shaft, axle/pivot components
  • Deck wear items: spindle assembly, pulleys, belts
  • Rolling gear: wheel assembly, tire, rim

Quick “system to part” map

System What it does Common parts you may replace
Fuel and air Feeds clean fuel and air to the engine fuel line, carburetor, air filter
Ignition Creates spark to start/run spark plug, ignition coil
Exhaust Routes exhaust safely, reduces noise muffler, exhaust gasket
Cutting deck Cuts grass evenly blades, spindle assembly, deck belt
Steering/brakes Controls direction and stopping steering shaft, puck brake

Why it matters

Knowing the part groups helps you troubleshoot faster. For example, a no-start problem usually points to fuel, air, or ignition, while uneven cutting points to deck leveling, blades, or spindles.

If you are diagnosing a starting issue, our riding lawn mower engine clicks but doesnt turn over video is a good next step.

Last updated: February 2026

On a Bolens lawn tractor, “660” is the model number, not an error code. It identifies the Bolens 660 THRU 688 front-engine lawn tractor so we can match the correct diagrams, parts (like steering and engine hardware), and service procedures in the owner's manual.

How to tell a model number from an error code

Most riding mowers and lawn tractors do not display numeric “error codes” the way many appliances do. Instead, you’ll usually see symptoms (no-crank, no-start, poor cut, vibration) that point to a system to troubleshoot.

Common places you’ll see 660 on this tractor:

  • The model tag/ID plate on the frame (often under the seat or near the engine)
  • Parts listings and exploded-view diagrams
  • The cover of the manual and parts references
  • On older paperwork such as purchase or service records

If you meant a problem code or symptom

If the tractor is acting up, use the symptom to narrow the fix. These are the most common “code-like” complaints we hear:

  • Engine clicks but won’t turn over (battery, starter circuit, safety switches)
  • Engine spins but won’t start (fuel, spark, air filter)
  • Engine dies when you release the brake (seat switch, brake switch, interlock)
  • Poor steering or excessive play (steering shaft, bushings, fasteners)

Quick checks that solve many no-start issues

  • Confirm the PTO/blade switch is OFF
  • Sit firmly in the seat and press the brake/clutch fully
  • Check battery terminals for corrosion and tightness
  • Verify fresh fuel and an open fuel shutoff (if equipped)
  • Inspect the air filter and spark plug condition

Parts that commonly come up during troubleshooting

If your issue involves exhaust leaks or steering looseness, these model-matched parts are commonly replaced:

Symptom What to inspect Example part on this model page
Puffing/ticking at engine exhaust Muffler mounting, gasket Gasket 692236
Loose steering feel Shaft wear, fasteners Steering shaft (listed in parts)

Why it matters

Using the correct model identifier (660) prevents ordering the wrong Bolens parts and helps you follow the right adjustment and safety-interlock procedures for your exact front-engine tractor.

Last updated: February 2026

This parts page is for the Bolens model 660 front-engine lawn tractor (a riding mower), not a Bolens push mower. For the Bolens 660 tractor, we use fresh regular unleaded gasoline; the exact fuel and ethanol guidance for your engine is listed in the owner's manual.

What to use in a Bolens 660 lawn tractor

  • Fresh regular unleaded gasoline (typical: 87 octane)
  • Clean fuel from a sealed container
  • Only the fuel type listed on your engine label and in the manual
  • Avoid mixing 2-cycle oil into the gas (4-cycle tractor engines use straight gasoline)

Ethanol guidance (what works best)

Most riding mower engines run best on gasoline with 10% ethanol (E10) or less. Higher-ethanol blends commonly cause hard starting and fuel-system deposits during storage.

Fuel choice OK for most riding mowers Why
Fresh regular unleaded (87 octane) Yes Correct combustion and easy starting
E10 or less Yes Helps protect fuel lines and carburetor
Old gas (over 30 days) No Causes varnish, surging, no-start

If you meant a Bolens push mower

Bolens push mowers use the same general rule (fresh regular unleaded), but the best answer depends on the exact push mower model and engine family. Match your mower’s model number to the fuel section in its manual, then follow the same storage steps below.

Why it matters

Using the right gasoline and keeping it fresh prevents carburetor clogging, reduces starting problems, and protects rubber fuel lines during seasonal storage.

Last updated: February 2026

Most common symptoms to help you fix your riding mowers & tractors

Choose a symptom to see related riding mower and lawn tractor repairs.

Main causes: damaged tie rods, bent or worn wheel spindle, worn front axle, damaged sector gear assembly…

Main causes: dead battery, stale fuel, bad starter solenoid, ignition system problem, bad ignition interlock switch, clo…

Main causes: worn or broken blade belt, broken belt idler pulley, blade clutch cable failure, bad PTO switch, damaged ma…

Main causes: engine overfilled with oil, leaky head gasket or sump gasket, damaged carburetor seals, cracked fuel pump, …

Main causes: punctured tire or inner tube, leaky valve stem, damaged wheel rim…

Main causes: unlevel mower deck, dull or damaged cutting blades, worn mandrel pulleys, bent mower deck, engine needs tun…

Main causes: worn or broken ground drive belt, bad seat switch, transaxle freewheel control engaged, transaxle failure, …

Main causes: faulty battery, bad alternator…

Main causes: shift lever needs adjustment, neutral control needs adjustment…

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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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