{"product_id":"castair-2-hp-single-stage-v2-cylinder-air-compressor-bare-pump-with-10-1a-flywheel-od-16-oz-oil-capacity-pk50","title":"Castair 2 HP Single Stage V2 Cylinder Air Compressor Bare Pump with 10 - 1A Flywheel OD 16 oz. Oil Capacity PK50","description":"\u003cp\u003eThe Castair PK50 is a 2 HP single-stage V-twin (V-2) cylinder bare pump with a 10\" (1A-series) flywheel and 16 oz. oil capacity. This is the step up from the single-cylinder PK20\/PK30 pumps — two cylinders in a V-configuration deliver more CFM per revolution and smoother compression than a single-cylinder design. The PK50 is the correct replacement pump when your existing Cast Air two-cylinder compressor pump has failed and the motor and tank are still serviceable.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eNote: Cast Air did not provide a dedicated manufacturer product page for this pump.\u003c\/strong\u003e Specifications are drawn from the product listing. Call us to confirm CFM output, max PSI rating, and motor\/pulley compatibility for your application before ordering.\u003c\/p\u003e\n\n\u003ch2\u003eV-2 Cylinder Configuration — What It Adds Over Single-Cylinder\u003c\/h2\u003e\n\u003cp\u003eA V-2 (V-twin) pump has two cylinders arranged in a V formation sharing a common crankshaft. Each cylinder fires on alternate half-strokes of the crankshaft, which means the pump compresses air more continuously than a single-cylinder design — the compression strokes are more evenly distributed over each crankshaft revolution. The practical result is:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eHigher CFM output for the same motor RPM compared to a single-cylinder pump of equivalent bore\u003c\/li\u003e\n\u003cli\u003eSmoother operation with less vibration (more balanced compression load)\u003c\/li\u003e\n\u003cli\u003eLower peak torque demand per stroke on the motor and belt drive\u003c\/li\u003e\n\u003cli\u003eMore consistent tank pressure recovery under load\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eFor a shop running air tools intermittently — impacts, ratchets, die grinders — the V-2 design keeps up better with cycling demand than a single-cylinder at the same HP rating.\u003c\/p\u003e\n\n\u003ch3\u003ePump Specification Details\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e PK50\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHP Rating:\u003c\/strong\u003e 2 HP\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStage:\u003c\/strong\u003e Single stage\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCylinders:\u003c\/strong\u003e 2 (V-2 configuration)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlywheel OD:\u003c\/strong\u003e 10\" (1A-series flywheel)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOil Capacity:\u003c\/strong\u003e 16 oz.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrive:\u003c\/strong\u003e Belt drive\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrice:\u003c\/strong\u003e $371.91\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eOil Capacity and Maintenance\u003c\/h2\u003e\n\u003cp\u003eThe PK50 uses 16 oz. of compressor oil — double the PK20\/PK30 capacity, reflecting the larger crankcase required for the V-2 configuration. Oil maintenance is critical:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eCheck oil level before each startup — a V-2 pump with low oil will seize the crankshaft bearings quickly under load\u003c\/li\u003e\n\u003cli\u003eChange oil at Cast Air's specified interval (confirm with documentation or call us)\u003c\/li\u003e\n\u003cli\u003eUse compressor pump oil specific to Cast Air or compatible oil-lubricated pump service\u003c\/li\u003e\n\u003cli\u003eOverfilling causes oil carry-over into the air stream — stay within the specified fill range\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhen Does a Shop Need the PK50 vs. PK30?\u003c\/h2\u003e\n\u003cp\u003eThe PK30 is 1.5 HP, single-cylinder. The PK50 is 2 HP, V-2 cylinder. Choose the PK50 when:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eYour existing compressor is V-2 configuration and the pump has failed — the PK50 is the replacement\u003c\/li\u003e\n\u003cli\u003eYou are building a new belt-drive compressor and need more CFM than a single-cylinder 1.5 HP pump provides\u003c\/li\u003e\n\u003cli\u003eAir tool demand in the shop has grown and the single-cylinder pump cannot keep up with duty cycles\u003c\/li\u003e\n\u003cli\u003eThe motor is rated at 2 HP or higher and the single-cylinder pump is the bottleneck\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eIf your existing compressor is single-cylinder and you are considering upgrading to PK50, confirm that the motor is rated for 2 HP — underpowering a V-2 pump will overload the motor on startup. The motor and pump HP ratings must match.\u003c\/p\u003e\n\n\u003ch3\u003eCast Air Bare Pump Comparison\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cstrong\u003ePK20 — 1.5 HP, 1-cylinder, 7.5\" flywheel, 8 oz. — $194.81\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003ePK30 — 1.5 HP, 1-cylinder, 10\" flywheel, 8 oz. — $241.01\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePK50 — 2 HP, V-2 cylinder, 10\" flywheel, 16 oz. — $371.91\u003c\/strong\u003e (this unit) — higher CFM, V-2 smoothness\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePK60 — 3.5 HP, V-2 cylinder, 10\" flywheel, 32 oz. — $432.74\u003c\/strong\u003e — heavy shop production use\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart Number:\u003c\/strong\u003e PK50\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer:\u003c\/strong\u003e Cast Air (Castair)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHP:\u003c\/strong\u003e 2\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStage:\u003c\/strong\u003e Single stage\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCylinders:\u003c\/strong\u003e 2 (V configuration)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlywheel OD:\u003c\/strong\u003e 10\" (1A-series)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOil Capacity:\u003c\/strong\u003e 16 oz.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDrive Type:\u003c\/strong\u003e Belt drive (flywheel included, belt not included)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrice:\u003c\/strong\u003e $371.91\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCFM\/PSI Rating:\u003c\/strong\u003e Not confirmed in listing — call for current performance data\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eManufacturer Data:\u003c\/strong\u003e Product page not available — specifications from product listing data\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eWhat Is Included\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1x Castair PK50 V-2 bare pump with 10\" flywheel\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eMotor, motor pulley, belt, tank, pressure switch, safety valve, and connecting hardware are not included. This is the pump assembly only. Confirm motor compatibility (2 HP minimum, correct RPM and shaft size) before purchasing.\u003c\/p\u003e\n\n\u003ch2\u003eWhy Buy From Air Compressor Factory Direct?\u003c\/h2\u003e\n\u003cp\u003eA V-2 pump replacement involves more compatibility checks than swapping a simple single-cylinder unit — motor HP, shaft size, motor pulley, belt length, and tank capacity all need to match or be adjusted. We have been working with Cast Air pump assemblies since 2016 and can help you confirm the complete component list before you order. Free shipping, free tech support, full manufacturer warranty on all Cast Air parts.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCast Air specialist\u003c\/strong\u003e since 2016\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree shipping\u003c\/strong\u003e on all orders\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFree tech support\u003c\/strong\u003e — we help you build the correct component list\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eFull manufacturer warranty\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eApplication guidance\u003c\/strong\u003e — we confirm motor compatibility before you commit\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCall 866-217-0063 for quick answers and help!\u003c\/strong\u003e\u003c\/p\u003e","brand":"Cast Air","offers":[{"title":"Default Title","offer_id":53342574608597,"sku":"PK50","price":685.86,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0622\/8466\/0949\/files\/CastAirTwoStageAirCompressorPump_3b7ef5c5-b0b3-4db0-b73d-479a7047103c.png?v=1772652791","url":"https:\/\/aircompressorfactorydirect.com\/products\/castair-2-hp-single-stage-v2-cylinder-air-compressor-bare-pump-with-10-1a-flywheel-od-16-oz-oil-capacity-pk50","provider":"Air Compressor Factory Direct","version":"1.0","type":"link"}