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BILT HARD Gas Engine Vertical Shaft, 173cc 4.4 HP 4-Stroke Gas Motor, Replacement Engine for Lawn Mower, EPA & CARB Compliant

  • Based on 895 reviews
Condition: New
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$179.99 Why this price?

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Availability: In Stock.
Fulfilled by Arkpower

Arrives Nov 21 – Nov 23
Order within 2 hours and 37 minutes
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Size: 173cc


Style: 4-Stroke Engine


Features

  • Unleash Dynamic Energy - Embrace the strength of a 173cc displacement 4-stroke vertical cylinder gas engine, boasting remarkable torque of 6.64 ft.lbs @2500 RPM. Capable of reaching a maximum speed of 3600 RPM, it's equipped with a staggering 4.4 maximum horsepower, all fueled by a 0.26-gallon tank.
  • Precision Shaft Specifications - Dive into the specifics of our engine with a 7/8-inch diameter shaft measuring 3.16 inches in length. The end is meticulously tapped with 3/8-inch - 24 UNF threads, further enhanced by a 3/16-inch keyway. The mounting pattern spans 8 inches, while the engine features a 3/8"-24 UNF tapped hole and a 0.079 x 0.34-inch through-hole.
  • Safety at the Forefront - Safety is paramount, evident in the built-in Force Air-Cooled, Splash Lubrication System, and Low oil shutoff function. Our engine spark plug system accommodates RA6HC/DCPR7E/DK7PTC spark plugs, offering a clearance of 0.027-0.031 inches. This engine is the perfect replacement for your lawnmower, ensuring a blend of power and security.
  • Vital Note - Kindly note that our engine is shipped dry to ensure freshness. Before starting, be sure to add gasoline and engine oil correctly (please note, oil is not included).
  • Certified Excellence - EPA and CARB Compliant. Our gas engine meets the highest standards of quality and compliance, proudly bearing both EPA and CARB certifications. Rest assured, each engine undergoes Oil Testing before packaging, so it may have a slight oily touch, signifying its 100% new condition.

Brand: BILT HARD


Speed: 3600 RPM


Horsepower: 4.4 hp


Product Dimensions: 11"W x 15.6"H


Material: Cast Iron


Model Number: RV170


Manufacturer: BILT HARD


Brand Name: BILT HARD


Horsepower: 4.4 hp


Speed: 3600 RPM


Item Weight: 12.5 Kilograms


Shaft Diameter: 3.27 Inches


Item Dimensions W x H: 11"W x 15.6"H


Material Type: Cast Iron


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Nov 21 – Nov 23

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Top Amazon Reviews


  • Great little motor
Size: 173cc Style: 4-Stroke Engine
I replace a briggs and stratton motor on a 20" push mower, using the one tapped hole and enclosed bolt, then tapped two other holes 3/8" x 16 to reuse original mounting bolts. i removed keyway that was on the shaft and old blade adapter and bolt worked perfectly. The original brake cable fit and worked perfectly. I bought an $8 throttle cable and installed it to complete the switch over. The engine holds 1/2 qt of engine oil. When checking oil using dipstick, be sure to read instructions. You check engine oil with the dipstick without screwing it into the engine. I filled with gas, pushed primer button twice, and engine started effortlessly with first pull and runs smooth and quiet. It has much more power than the briggs motor I removed. After running engine for 5 minutes or so, I changed the oil. Note you must flip mower upside down to drain oil, there is no drain plug. So far I am very impressed with this little motor. ... show more
Reviewed in the United States on August 4, 2024 by Sandy

  • Starts on the first pull every time.
Size: 79cc Style: 4-Stroke Engine
I’m very pleased with this motor. I mounted it on an edger and it works great. I run it in low speed for edging and it uses very little gas.
Reviewed in the United States on September 30, 2024 by David Cagnolatti

  • Nice engine
Size: 212cc Style: 4-Stroke Engine
I used the engine to repower my 1954 gravely tractor. So far it’s working fine. It’s a little bit faster than the previous engine so I throttled down speed a bit. I like the ease of starting.
Reviewed in the United States on August 12, 2024 by Blasig Electric LLC

  • Runs Well, but Evaporates/Leaks Gas
Size: 173cc Style: 4-Stroke Engine
Motor runs well. Throttle adjustment is useful for adjusting to needs. Major downside is my entire gas tank evaporates between uses. My other newer motors do not do this. Customer support is friendly, but unable to offer remedy to address this. I use ethanol free gasoline, and this is a bummer, since it is more expensive to lose to leakage. / Update: Customer service assisted me in resolving the issue. ... show more
Reviewed in the United States on October 4, 2024 by H.J.

  • Important review, please read before buying. It could save you a lot of time.
Size: 173cc Style: 4-Stroke Engine
This is a good value engine, but I did have to tinker. First off, this is the exact same engine as Harbor freights predator line. The manual is word for word and everything on the engine is the same but the cover. This came from the same factory, but this is 50 dollars cheaper. I bought the 173cc lawn mower engine. With that said this engine died on me every 20 minutes. The fix is easy and I think it explains most of the dead engines from the 1 star review. They did make the troubleshooting time worth it for me. The problem is the emergency stop circuit. I would describe this as a design flaw. The emergency stop circuit is very simple. There is a terminal on the ignition coil. This terminal goes to a wire that screws onto part of the engine. The other end of the wire that connects to the engine has a terminal as well. A lever makes contact with that terminal to ground the circuit and shut the engine off. The lever goes to the cable on your mower. The problem is there is no adjustment for that terminal to lever connection. For me when the mower got hot the terminal would deform and make contact to the lever. This caused sputtering and then eventually it would shut down until the engine cooled and terminal no longer made contact with the lever. The fix is easy, about 10 minutes and free. Take the 3 screws off the cover. Remove the cover. Take the 3 nuts off the internal cover and remove those. Follow the wire from the ignition coil to where it connects to the engine and bend that terminal down slightly. When the engine is running verify you have about half the lever travel with engine on and half with engine off. This will mean a safety factor on both sides. You can also use a multi meter. Connect one lead to the wire and the other to the engine body. Adjust until you get continuity for half the lever travel and no continuity for the other half of the travel. A troubleshooting step is to remove the wire from the ignition coil when your unit won't start. If you do this you will have no means to turn the engine off. You will have to run out of gas, pull the spart plug wire, or ground the terminal on the ignition coil. Be careful of the mower blade. Hopefully this helps. ... show more
Reviewed in the United States on April 27, 2024 by Amazon Customer

  • Go ahead, do it, not sorry.
Size: 173cc Style: 4-Stroke Engine
I am not a mechanic, but a hospital pharmacist, however I like machines and I like to buy something and have it last, and last, and last. My old Wrangler Rubicon has 200 M on it and runs like a kitten purr still...it may be my last car. My old Badger rototiller engine gave out after years of use. Should I let go of $600 for a new one or try a new engine?....that is always a gamble. I bought this Bilt Hard....it fit the rototiller after a few new frame attachment holes and a 5/8 inch pulley since my old one was 3/4. I had to fool around with this since I put too much oil in and also fouled my carburetor by turning the engine upside down. But I figured that out and blew out the carb and it runs great and has the power to till my garden. It took a little work, if yours is a straight replacement it will be easy. It runs perfectly for me. ... show more
Reviewed in the United States on July 12, 2024 by John R.

  • Great for log splitter
Size: 173cc Style: 4-Stroke Engine
After cutting down the shaft and key this work great on my log splitter. The hole pattern lined up with the original tecumseh bolt pattern that already existed. Only change would have been to make all the mounting holes the same type. One was threaded and the others were through holes.
Reviewed in the United States on August 28, 2024 by Alex B. Alex B.

  • Motor
Size: 212cc Style: 4-Stroke Engine
Great product great price
Reviewed in the United States on September 28, 2024 by Pmccarthy

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