20405600 Return Line | Genuine Volvo Penta Part

🔧 Product Description

Genuine Volvo Penta early turbocharger oil-return line used on TD520GE engines through serial number 942182. It is replaced by return line 20555279 from serial number 942182 onward.

🚤 Compatibility

Typically suits:

• Volvo Penta TD520GE
• Volvo Penta TAD520GE
• Volvo Penta TAD520VE

• Engine Family: TD, TAD
• Serial Range: Part has a unique replacement. The new part may be used in any case. The old part may only used for engines that were org. eq. with this part., SN-942182

⚙️ Key Features

• Gravity-drain turbo oil-return line
• Early design for TD520GE through SN 942182
• Later replacement configuration uses 20555279 from SN 942182
• Works with return line 20405791 and plane gasket 20405790
• Must maintain unrestricted downhill oil drainage
• Engine type: Volvo Penta 5-litre four-cylinder turbocharged industrial diesel

🔌 Function

Drains lubricating oil from the turbocharger bearing housing back to the engine crankcase.

⚠️ Common Signs of Failure

• Oil leakage around the return pipe
• Blue smoke from oil backing up in the turbo
• Restricted or carboned drain passage
• Cracked or distorted line
• Turbo seal leakage caused by poor drainage

🛠️ Service Notes

• Renew the sealing washers, O-rings or gaskets at each end rather than reusing them, and check the union faces are clean and unmarked
• Fit the line without pulling it into place; a return line that has to be strained to line up will crack or chafe through in service
• Keep the original routing, clips and protective sleeving so the line stays clear of hot and moving parts and cannot rub
• Do not kink a line, and do not straighten and re-bend a formed metal one — cap the open ends while the system is apart so no dirt gets in
• Tighten the unions to the figures given in the workshop manual for your engine, then run up and check both ends for weeps before closing the access

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 20405600 - early return line through SN 53851527
• 20555279 - later return line from SN 53851528

OEM / Related Numbers

• 20405791 - companion return line
• 20405790 - plane gasket
• 20405822 - related O-rings
• 984734 - flange screws

📦 Condition

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