How much does it cost to repair a hydrostatic transmission on a lawn mower?
Hydrostatic transmission repairs are typically a riding-mower cost; Craftsman model 917387430 is a walk-behind rotary mower and normally does not use a hydrostatic transmission. For riding mowers that do, repairs commonly run from a few hundred dollars for service to $1,300+ for the transmission itself, and up to about $2,500 for a full replacement with labor.
What you’re likely dealing with on model 917387430
Most “won’t move” complaints on a walk-behind mower are caused by drive system wear or adjustment, not a hydrostatic unit.
- Check the drive control cable for slack or binding
- Inspect the drive belt and pulleys for glazing, cracking, or slipping
- Clean under the drive cover (grass buildup can stop engagement)
- Check for loose fasteners and worn wheel hardware
- Stop the engine and disconnect the spark plug wire before any inspection (per the 917387430 owner’s manual)
Cost ranges (typical)
These ranges help you decide whether to repair or replace.
| Repair scenario | Typical cost range | Notes |
|---|---|---|
| Basic diagnosis and adjustment | $75 to $200 | Cable/belt checks, cleaning, minor tuning |
| Drive belt or pulley service (walk-behind) | $100 to $300 | Parts plus labor varies by shop |
| Hydrostatic transmission replacement (riding mower) | $1,300 to $2,500 | Higher end includes labor and fluid service |
Parts that commonly affect “drive” performance on this mower
If you’re servicing the cutting system at the same time, replace worn hardware so the deck runs smoothly.
- Lawn mower blade 532406713 if the blade is bent, nicked, or badly worn
- Blade adapter wear can cause vibration and poor cut quality
- Fasteners and handle hardware should be tightened per the maintenance schedule
Why it matters
A slipping belt, clogged drive cover, or loose hardware can mimic a “transmission problem.” Fixing the real cause first prevents repeat failures and helps the mower run safely (excessive vibration is a sign of damage).
Last updated: January 2026
What kind of gas do I put in my lawn mower?
For the Craftsman 917387430 rotary lawn mower, we recommend using fresh regular unleaded gasoline (most commonly E10). Fill the tank only when the engine is off and cool, and wipe up any spills before starting, as outlined in the 917387430 owner's manual.
What to use (and what to avoid)
- Use fresh, clean regular unleaded gasoline (E10 is typical).
- Use a clean fuel can; replace it if it starts to rust.
- Avoid stale gas (old fuel is a common no-start cause).
- Avoid storing gas in the mower from one season to the next.
- Never refuel indoors, or while the engine is running or hot.
Quick fuel checklist for reliable starting
If your mower is hard to start or loses power, fuel quality is one of the first things we check:
- Confirm there is fuel in the tank.
- Make sure the fuel smells fresh (not varnish-like).
- Drain and replace fuel if you suspect water contamination.
- Clean up spilled gasoline before starting.
- Let the engine cool several minutes before refueling.
Fuel storage guidance
The manual calls out storage habits that prevent fuel-related problems.
| Situation | What we recommend | Why |
|---|---|---|
| Fuel left over after mowing season | Do not store it in the mower | Helps prevent stale fuel issues |
| Gas can shows rust or dirt | Replace the gas can | Rust and debris can cause running problems |
| Storing mower in a building | Let engine cool; avoid fumes near flame/sparks | Reduces fire risk from vapors |
Why it matters
Stale or contaminated gasoline is a top cause of “does not start” and “loss of power” symptoms on walk-behind mowers. Using fresh regular unleaded fuel and handling it safely protects the carburetor, improves starting, and keeps performance consistent.
Last updated: January 2026
What model number is the Craftsman 917387430?
The model number for this Craftsman walk-behind rotary lawn mower is 917.387430 (often written without the dot as 917387430). You’ll see it printed on the mower’s model label and on the cover page of the 917387430 owner's manual.
Where to find the model number on the mower
We recommend checking these common locations on Craftsman walk-behind mowers:
- On the rear of the mower deck near the discharge chute
- On the deck top surface near the engine mounting area
- On the handle bracket area (near the lower handle)
- On a sticker or metal tag that also lists serial information
Why the dot matters (917.387430 vs 917387430)
Both formats refer to the same mower; the dot is a Craftsman formatting style used in manuals and parts lists.
| You might see it as | What it means | When it’s used |
|---|---|---|
| 917.387430 | Same model number | Common in printed manuals and diagrams |
| 917387430 | Same model number | Common in online parts lookups |
Related parts you may see tied to this model
When you’re confirming the model for parts ordering, these are common items listed for Craftsman 917387430:
- Lawn mower blade 532406713 (blade size and mounting must match your deck)
- Lawn mower blade adapter 581547901 (connects the blade to the crankshaft)
- Rope guide 586122501 (helps route the starter rope at the handle)
Why it matters
Using the exact model number (917.387430 or 917387430) ensures you get the correct diagrams and compatible parts, especially for deck hardware, blade mounting components, and handle controls.
Last updated: January 2026





