Honda GCV170, 166cc overhead valve
The GCV170 is the engine on Honda's HRN216 mowers. It replaced the GCV160 on Honda mowers in 2019. Unlike the GCV160 it is an overhead-valve engine, and on the HRN216 it has an automatic choke.
GCV170166cc OHVAuto choke
Specs and part numbers at a glance
- Model sticker reads
- GCV170
- Displacement
- 166 cm3 (10.1 cu in)Honda's HRN216 spec sheet rounds it to 167 cc.
- Bore x stroke
- 60 x 59 mm
- Spark plug
- NGK BPR5ESNGK BPR6ES on pressure washer versions.
- Plug gap
- 0.70–0.80 mm (0.028–0.031 in)
- Oil
- SAE 10W-30, API SJ or later. Capacity 0.40 L (13.5 oz)Honda's web spec page says 0.41 L. Fill to the upper dipstick mark either way.
- Fuel
- Unleaded, 86 pump octane or higher, up to 10% ethanol. Tank 0.91 L (0.24 gal)
- Air filter
- Paper element 17211-Z8B-901
- Idle speed
- 1,700 ± 150 rpmHonda lists idle and valve clearance as dealer adjustments.
- Valve clearance (cold)
- IN 0.10 ± 0.02 mm, EX 0.10 ± 0.02 mm
Find the model number
Honda puts the engine model on a sticker on the engine. It starts with G, so this one reads GCV170. The serial number is stamped into the side of the engine: 4 or 5 letters followed by 7 digits. The engine type code (up to 4 characters) is stamped close to the serial number. You need the type code to pick the right parts in Honda's parts catalog. This is marker D on the drawing below.
Where the number is stamped
- ABriggs & Stratton: stamped into the metal just above the spark plug. You may need a flashlight.
- BBriggs & Stratton: stamped on a small metal plate between the valve cover and the air filter.
- CBriggs & Stratton: stamped on the sheet metal above the muffler, which can be on either side.
- DHonda: the model (it starts with G, like GCV170) is on a sticker on the engine. The serial number and type code are stamped into the side of the engine.
Mowers that use this engine
Honda's own HRN spec sheet lists this engine on every HRN216 model.
| Mower | Model no. | What the maker lists |
|---|---|---|
| Honda HRN216 (VKA, VLA, VYA, PKA) | HRN216 | Honda HRN specification sheet, 2019 |
Parts and part numbers
Check the number against the parts list for your exact model before you order.
| Part | Part number | Notes |
|---|---|---|
| Spark plug | NGK BPR5ES | Honda owner's manual |
| Air filter element | 17211-Z8B-901 | Honda dealer listing for GCV170 and HRN216 |
Tools you need
- Spark plug wrench
- Wire-type gap gauge
- Oil drain pan
- Clean rags
- Gloves
Maintenance and repairs, step by step
Replace the spark plug
Check once a year or every 100 hours. Replace every 2 years or 200 hours.
| 01 | Pull the cap off the spark plug and clean dirt away from around it. | Engine cold. |
| 02 | Remove the plug with a spark plug wrench. | |
| 03 | Replace it if the electrodes are worn, it is badly fouled, or the sealing washer is damaged. | NGK BPR5ES on mowers. |
| 04 | Measure the gap and set it to 0.70–0.80 mm (0.028–0.031 in) by carefully bending the side electrode. | |
| 05 | Thread the plug in by hand so it can't cross-thread. | |
| 06 | Tighten with the wrench: a new plug 1/2 turn after it seats, a reused plug 1/8 to 1/4 turn. | From Honda's owner's manual. Too loose and it overheats; too tight and it can strip the head. |
| 07 | Push the cap back on. |
Clean or replace the air filter
Clean every 3 months or 25 hours; more often in dust.
| 01 | Unclip the air cleaner cover. | |
| 02 | Take out the paper element. | Element 17211-Z8B-901. |
| 03 | Tap it several times on a hard surface, or blow compressed air at no more than 30 psi (207 kPa) through it from the engine side. | Never brush it; that pushes dirt into the paper. |
| 04 | Wipe the case and cover with a damp rag. Keep dirt out of the air duct that leads to the carburetor. | |
| 05 | Refit the element and the cover. | Replace the element every 2 years or 200 hours, or sooner if it is damaged. |
Change the oil
After the first month or 5 hours, then every 6 months or 50 hours. Every 25 hours under heavy load or in hot weather.
Safety Let a hot engine cool enough to touch the muffler area safely, and work outdoors. Keep sparks and flames away from the fuel tank.
| 01 | Run the engine briefly so the oil is warm, then stop it and pull the plug cap. | Warm oil drains faster. |
| 02 | Turn the fuel valve OFF if the engine has one. | |
| 03 | Remove the oil cap and dipstick. Tilt the engine with the muffler side down so the oil runs out of the filler neck. Never tilt it carburetor side down. | |
| 04 | Set the engine level and refill with SAE 10W-30 (API SJ or later). Refill amount is about 0.40 L (13.5 oz). | Some oil stays in the engine, so use the dipstick, not the bottle. |
| 05 | Check with the dipstick inserted but not screwed in. Fill to the upper mark only. | |
| 06 | Refit the cap and take the old oil to a recycling point. |
Check the flywheel brake
Every 6 months or 50 hours.
| 01 | With the engine running, let go of the blade control bar. | The engine should stop quickly. |
| 02 | Stop the engine and pull the plug cap. Check the clearance at the flywheel brake lever. | Honda's limit is 2 mm (0.08 in). |
| 03 | If it is less than 2 mm, or the engine doesn't stop quickly, take it to a Honda dealer. | Do not adjust or bypass the brake. |
Honda maintenance schedule
Whichever comes first, months or hours.
| When | What to do |
|---|---|
| Before each use | Check oil level. Check air filter. |
| First month or 5 hours | Change oil. |
| Every 3 months or 25 hours | Clean air filter (more often in dust). |
| Every 6 months or 50 hours | Change oil. Clean air filter. Check flywheel brake. |
| Every year or 100 hours | Check and adjust spark plug. Clean spark arrester if fitted. Idle speed, fuel tank and filter, valve clearance: dealer. |
| Every 2 years or 200 hours | Replace air filter. Replace spark plug. Check fuel lines (dealer). |
Troubleshooting by symptom
| Symptom | Likely cause | What to do |
|---|---|---|
| Won't start | Fuel valve off, choke off on a cold engine, or flywheel brake lever not held | Fuel valve ON. On manual-choke types, choke for a cold start. Hold the blade control bar against the handle. |
| Won't start after storage | Old fuel | Drain the tank and refill with fresh gasoline. Honda lists bad fuel as a main cause of hard starting. |
| Starts, then floods or won't restart | Spark plug wet with fuel | Dry the plug, reinstall, and start with the choke OFF and throttle at FAST. |
| Lacks power | Clogged air filter or old fuel | Clean or replace the air filter, then refuel with fresh gasoline. |
| Still won't run after the above | Clogged fuel filter or carburetor, ignition fault, stuck valves | Honda sends these to a dealer or the shop manual. See our carburetor job for float bowl cleaning. |
| Blade keeps turning after you let go of the bar | Worn flywheel brake | Stop using the mower and take it to a dealer. Do not bypass the brake. |
Owner's manuals and parts lookups
These go to the maker's own sites.
- Honda GCV170 / GCV200 owner's manual (PDF) Specs, schedule, plug, oil
- Honda GCV170 specifications
- Honda: find the model and serial number
- Honda engine parts catalog Needs the type code
Something wrong or missing?
Tell us the full model number on your engine and what you found.