22275074 Pump Piston | Genuine Volvo Penta Part

🔧 Product Description

The strength required to steer a boat with a hydraulic steering system is inversely proportional to the number of turns of the wheel lock-to-lock. Wheel turns are determined by the ratio between the cylinder volume, the pump displacement and the free movement of the steering device. A large cylinder volume with a small pump displacement gives more wheel turns; a small cylinder volume with a large pump displacement gives fewer. Fewer wheel turns means quicker steering response but more effort; more wheel turns means slower response but less effort. The helm pumps are available in three displacement sizes - 28 cc, 33 cc and 39 cc - each in three mountings: front mount, rear mount and tilt mount. This is the 33 cc rear mount pump, with 7 pistons, a 70 bar relief valve setting and a maximum wheel diameter of 711 mm.

🚤 Compatibility

• Engine Family: D
• HP Range: 13-435 HP

Full model list at the end of this description.

⚙️ Key Features

• 33 cc displacement per wheel revolution
• Rear mount
• Seven piston pump
• 70 bar relief valve setting
• For steering wheels up to 711 mm in diameter
• 5.427 kg, listed for 50 applications
• Replaces 21639574
• Rear mount helm pump
• 7 pistons
• Maximum wheel diameter 711 mm
• 5 kg
• Displacement per rev: 33 cc
• Max wheel diameter: 711 mm
• Pistons: 7
• Mounting: Rear mount helm pump
• Relief valve setting: 70 bar
• Weight: 5 kg
• Fits: Volvo Penta hydraulic steering systems

🔌 Function

Converts steering wheel rotation into pressurised hydraulic oil flow to the steering cylinder.

⚠️ Common Signs of Failure

• Heavy, notchy or inconsistent steering
• Wheel turning without the drive following, from internal bypass
• Hydraulic oil weeping at the shaft seal or the port fittings
• Air drawn into the circuit giving a spongy helm

🛠️ Service Notes

• The same 33 cc pump is 22275071 in front mount and 22275077 in tilt mount, so check the mounting before ordering
• Match the pump displacement to the cylinder volume already fitted, since the pair together set the number of wheel turns lock to lock
• Bleed the circuit fully after fitting and check the level with the steering held hard over each way
• Displacement and mounting together are the product: the same 33 cc displacement is also listed as 22275071 and 22275077, and the other rear mount pumps are 22275073 and 22275075
• Tilt mount pumps are rated to a 508 mm wheel against 711 mm for the front and rear mount pumps
• Cylinder volume and pump displacement together set how many turns the wheel takes lock to lock

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 22275074 → Supersedes 21639574 → Supersedes 21135045 → Supersedes 3809976

OEM / Related Numbers

• 21639574 earlier number superseded by this part
• 21135045 earlier number superseded by this part
• 3809976 earlier number superseded by this part

📦 Condition

• Genuine Volvo Penta part
• Brand new
• Supplied in original or equivalent packaging

🔎 Full Model Compatibility

Typically suits:

• Volvo Penta D3-220I-G, D3-140I-G, D3-110I-G, D3-150I-G, D3-170I-G, D3-200I-G, D3-110I-H, D3-150I-H, D3-170I-H, D3-200I-H, D3-220I-H, D3-140I-H
• Volvo Penta D13C1-A MP, D13C2-A MP, D13B-A MP, D13B-H MP, D13B-G MP, D13B-K MP, D13B-B MP, D13B-J MP, D13C6-A MP
• Volvo Penta D11C1-A MP, D11C3-A MP, D11B3-A MP, D11A-C, D11A-D, D11A-E, D11B1-A MP
• Volvo Penta D2-40F, D2-55F, D2-50F, D2-75F, D2-60F
• Volvo Penta D4-260I-F, D4-180I-F, D4-225I-F, D4-300I-F
• Volvo Penta D6-300I-F, D6-330I-F, D6-370I-F, D6-435I-F
• Volvo Penta D8A5-A MH, D8A6-A MH, D8A1-A MP, D8A3-A MP
• Volvo Penta D1-30F, D1-13F, D1-20F
• Volvo Penta D9A2H, D9A2K