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Oil Tank Support Bracket – Fits Mercury Marine, Volvo Penta (Replaces 855388, 834751)

Regular price $26.55

Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This Oil Tank Support Bracket provides crucial support for the oil tank in specific Mercury Marine and Volvo Penta diesel engine applications. It is designed primarily for CMD (Cummins MerCruiser Diesel) 2.8L and 4.2L engine models, ensuring the oil tank is mounted securely to prevent vibration and stress on connected components.

This component is a direct replacement for Mercury Marine part numbers 855388 and 834751, and Volvo Penta equivalents 855388 and 834751.

  • Installation: Mounts directly to the engine or oil system assembly.
  • Dual-Functionality Note: While used as an oil tank bracket in Mercury engines, this part number is also referenced as an exhaust tube for some Volvo Penta applications (L=2x160mm, for engines with Drive Unit 280).

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket brands.

Brand Part Number
Mercury Marine 855388
Mercury Marine 834751
Volvo Penta 834751
Volvo Penta 855388

Engine & Model Compatibility

Confirm your engine model and year in the table below.

For CMD (Cummins MerCruiser Diesel) applications, this part supports the oil tank on various 2.8L and 4.2L series engines.

For Volvo Penta applications, this part is referenced for several models, primarily older V6 and V8 engines, where it may function as an exhaust hose.

Brand Model Rated HP Stroke Years OEM Part No. Notes
CMD 2.8 EI 165 165 4-Stroke 855388 VM 169 I/L4 Engine
CMD 2.8 ES 165 165 4-Stroke 855388 VM 169 I/L4 Engine
CMD 4.2 EI 250 250 4-Stroke 855388 VM 254 I/L6 Engine
CMD 4.2 EI 270 270 4-Stroke 855388
CMD 4.2 EI 300 300 4-Stroke 855388 VM 254 I/L6 Engine
CMD 4.2 EI 320 320 4-Stroke 855388
CMD 4.2 ES 250 250 4-Stroke 855388 VM 254 I/L6 Engine
CMD 4.2 ES 270 270 4-Stroke 855388
CMD 4.2 ES 300 300 4-Stroke 855388 VM 254 I/L6 Engine
CMD 4.2 ES 320 320 4-Stroke 855388
CMD 4.2 MI 200 200 4-Stroke 855388
CMD 4.2 MI 230 230 4-Stroke 855388
CMD 4.2 MS 200 200 4-Stroke 855388
CMD 4.2 MS 230 230 4-Stroke 855388
D2.8L 165 D-TRONIC 165 4-Stroke 855388 VM 169 I/L4 Engine
D4.2L 200 LD 200 4-Stroke 855388 VM 254 I/L6 Engine
D4.2L 250 D-TRONIC 250 4-Stroke 855388 VM 254 I/L6 Engine
D4.2L 300 D-TRONIC 300 4-Stroke 855388 VM 254 I/L6 Engine
Volvo Penta AQ175 834751
Volvo Penta AQ205 834751
Volvo Penta AQ430A/B 834751 GM V6 (1993 & Before)
Volvo Penta AQ432 834751
Volvo Penta AQ434 834751 GM V6 (1993 & Before)
Volvo Penta 5.0L Up to 1993 834751 GM 305 CID, V8 S.B.
Volvo Penta 5.7L Up to 1993 834751 GM 350 CID, V8 S.B.

Technical Specs

Product Type
Oil Tank Support Bracket
Installation
Engine/Oil System Mounting
Other Technical Attributes
For Engine With Drive Unit 280, L=2x160mm (regarding Volvo Penta applications)

What’s in the Box

  • 1 x Bracket-P/S Tank (855388/834751)

Installation Notes

  1. Disconnect the negative battery terminal to ensure safety.
  2. Locate the existing power steering fluid or diesel oil tank and its support bracket.
  3. Carefully unbolt and remove the old or damaged bracket, ensuring the tank is supported.
  4. Align the new support bracket with the engine mounting points.
  5. Secure the new bracket using the original mounting hardware, tightening bolts to the manufacturer's specified torque.
  6. Re-secure the tank to the new bracket and reconnect the battery. Check for stability before starting the engine.

Troubleshooting & FAQ

Is this part an oil tank bracket or an exhaust hose?

This part number has a dual function depending on the make. For the listed Mercury Marine / CMD engines, it is an Oil Tank Support Bracket. For the specified Volvo Penta models, the same part number is cross-referenced as an Exhaust Hose/Tube. Verify your original part's function and shape before ordering.

How do I confirm if this bracket will fit my specific engine?

The most reliable method is to match your old part number to one of the equivalents in our Part Number Matrix. Additionally, cross-reference your engine model and year with our compatibility table. When in doubt, visually compare your existing part to our product photos.

What are the signs that my original support bracket needs to be replaced?

Common indicators of a failing bracket include visible cracks, significant rust or corrosion, and excessive vibration or movement of the oil tank. A broken bracket can lead to component stress and potential fluid line leaks.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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