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How much does it cost to repair a hydrostatic transmission on a lawn mower?
Hydrostatic transmission repairs are typically a riding-mower cost category; most Craftsman walk-behind mowers like model 917377790 use a belt-and-pulley drive system instead of a hydrostatic transmission. For this mower, repair costs usually center on drive components (belt cover, pulleys, wheels) rather than a transmission rebuild; confirm your drive layout in the 917377790 owner's manual.
Typical cost ranges (what you can expect)
Hydrostatic transmission work (common on riding mowers) is expensive because the unit is often replaced as an assembly.
- Diagnostic labor: commonly 0.5 to 1.5 hours
- Minor service (linkage adjustment, fluid service where applicable): typically lower-cost
- Major repair (pump/motor failure): often becomes a full transmission replacement
- Walk-behind drive repairs (belts, pulleys, wheels): usually far less than hydrostatic work
Quick comparison
| Mower type | Drive type | Usual “big ticket” repair | Cost tendency |
|---|---|---|---|
| Riding mower | Hydrostatic | Transmission replacement | High |
| Walk-behind (like 917377790) | Belt/pulley self-propel | Pulley, wheel, belt-related repairs | Moderate |
What to check on Craftsman 917377790 before pricing a “transmission” repair
Many “won’t move” complaints on a self-propelled walk-behind mower trace back to wear items and hardware.
- Inspect the drive area under the cover for packed grass and debris
- Check for loose fasteners (the manual’s maintenance schedule calls this out)
- Look for a damaged or wobbling pulley; a worn idler can cause slipping
- Check the drive wheel condition and engagement
- Verify the control cable/bail fully engages the drive
If you find pulley wear, the parts list for this model includes idler pulleys such as the husqvarna lawn mower idler pulley 532166042. For broader parts lookup by model number, we also support search on Sears PartsDirect.
Why it matters
Pricing depends on whether you are dealing with a true hydrostatic unit (riding mower) or a self-propelled walk-behind drive. Misidentifying the drive system can lead to overestimating the repair and replacing the wrong components.
Last updated: February 2026
Should I use 87 or 89 gas for lawn mower?
Use 87-octane regular unleaded gasoline in your Craftsman 917377790 gas walk-behind lawn mower; our manual specifies a minimum of 87 octane. Using 89 is not necessary for normal operation, as long as the fuel is fresh and clean (and you do not mix oil into the gas). See the owner's manual for the exact fueling and storage steps.
What to use (and what to avoid)
- Use fresh, clean, regular unleaded gasoline (87 octane or higher).
- Fill the tank to the bottom of the filler neck; do not overfill.
- Do not mix oil with gasoline (this is a 4-cycle mower engine setup).
- Buy only what you can use in about 30 days to keep fuel from going stale.
- Wipe up any spilled fuel before starting.
87 vs 89: quick comparison
| Fuel choice | Works in Craftsman 917377790? | When it makes sense |
|---|---|---|
| 87 octane (regular) | Yes (recommended) | Everyday mowing; best match to the manual guidance |
| 89 octane (mid-grade) | Yes | Only if 87 is unavailable; it will not improve power in normal conditions |
If the mower will sit for 30 days or longer
Alcohol-blended fuels can pull in moisture during storage, which can lead to fuel system problems. For longer storage, we follow the manual approach:
- Run the engine until the tank and fuel system are empty.
- Store the mower indoors if possible, and let the engine cool before storing.
- Start next season with fresh fuel.
Why it matters
Correct octane and fresh fuel help prevent hard starting, rough running, and carburetor issues. Most “fuel problems” on walk-behind mowers come from stale gas or storage with fuel left in the system, not from using 87 instead of 89.
Parts that commonly come up with fuel and starting issues
If you are troubleshooting starting or drive issues while you are maintaining the mower, these model-matched parts are commonly involved in related repairs:
- Rope guide 586122501 (starter rope routing and recoil pull feel)
- Belt cover 532180191 (access for inspecting the drive belt area)
You can also look up additional replacement parts for Craftsman 917377790 on this model’s parts list, or search by model number on Sears PartsDirect.
Last updated: February 2026
What are the common problems with Craftsman lawn mowers?
Common problems we see on the Craftsman 917377790 gas walk-behind lawn mower include loss of power, uneven cutting, excessive vibration, and a starter rope that’s hard to pull. These symptoms usually come from blade condition, deck buildup, airflow issues, or control adjustments covered in the 917377790 owner's manual.
Most common symptoms and likely causes
- Loss of power: heavy grass load, dirty air filter, grass buildup under the deck, oil level too high, walking speed too fast
- Poor cut (uneven): worn or bent blade, loose blade hardware, uneven wheel height settings, deck packed with clippings
- Excessive vibration: loose or damaged blade, bent crankshaft (often after striking an object)
- Starter rope hard to pull: flywheel brake engaged, blade dragging in grass, damaged blade adapter
Quick checks we recommend first
- Disconnect the spark plug wire before working near the blade.
- Tip the mower safely (air filter and carburetor side up) and clean the underside of the deck.
- Inspect the blade for bends, cracks, or heavy nicks; replace if damaged.
- Set all wheels to the same cutting height.
- Verify engine oil is at the correct level (overfill can reduce power).
Parts that commonly come up on this model
If inspection shows wear or damage, these model-matched parts are often involved:
| Area | Part to check | What it affects |
|---|---|---|
| Cutting | Lawn mower blade 532180459 | Cut quality, vibration, load on engine |
| Starter routing | Rope guide 586122501 | Rope wear, pull feel |
| Belt area protection | Belt cover 532180191 | Debris intrusion around drive components |
Why it matters
Running with a dull or damaged blade or a deck packed with clippings increases engine load and vibration; that shortens component life and can lead to harder starting and poorer cut quality.
You can order replacement parts for the Craftsman 917377790 from the parts list for this model, or search by model number on Sears PartsDirect.
Last updated: February 2026
What year is Craftsman Model 917377790?
Craftsman model 917377790 is a walk-behind rotary lawn mower model series that was sold in the early 2010s. The exact build year is identified from the mower’s product ID or date code on the unit (not from the model number alone); we use the 917377790 owner's manual to match the correct model and then confirm the date code on the mower.
Where to find the build date on the mower
Look for a sticker or stamped code in one of these common spots:
- Under the rear discharge door or on the rear deck lip
- On the deck near the engine mounting area
- On the handle support bracket or near the height adjuster
- On the engine shroud (engine model and code are often listed there)
How to decode what you find
Different Craftsman walk-behind mowers and engines use different formats, but these checks work well:
- Product/serial label present: use the serial or date code to determine the year.
- Engine code present (common): the engine’s code often includes a manufacture date; that date is a reliable indicator of the mower’s timeframe.
- Only the model number present: the model number confirms parts compatibility, not the exact year.
Quick reference: model number vs. date code
| Item you have | What it tells you | Best use |
|---|---|---|
| Model number (917377790) | Which parts diagrams and parts fit | Ordering parts and repairs |
| Serial/date code label | The mower’s build timeframe | Determining the year |
| Engine model and code | Engine build date and spec | Engine parts and tune-up |
Why it matters
The year matters most when you are matching engine tune-up parts, drive system components, and handle/control hardware. For example, this model’s parts list includes items like the lawn mower blade 532180459 and rope guide 586122501, and the correct version depends on matching the exact model and configuration.
You can order replacement parts for Craftsman 917377790 from the parts list for this model, or search by model number on Sears PartsDirect.
Last updated: February 2026
