Hardware Kit for MAR501 Manifold – Fits OMC/Volvo Penta 5.0L/5.7L V8
Hardware Kit for MAR501 Manifold – Fits OMC/Volvo Penta 5.0L/5.7L V8 is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
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Hardware Kit for MAR501 Manifold – Fits OMC/Volvo Penta 5.0L/5.7L V8
Product Details
This Hardware Kit for MAR501 Manifold is designed for Volvo Penta and OMC V8 5.0L (305 CID) and 5.7L (350 CID) GM-based marine engines manufactured from 1993 and newer. It provides all the necessary components for a direct bolt-on installation of the MAR501 exhaust manifold.
It serves as a direct replacement for OEM and aftermarket part numbers including OMC 3856961 and GLM 13060.
- Direct bolt-on installation method.
- Made to exact OEM specifications for a precise fit.
- Includes essential components like a thermostat, gasket, and O-ring.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| OMC | 3856961 |
| GLM | 13060 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
For Volvo Penta: This kit fits V8 5.0L and 5.7L GM-based engines from 1993 onward.
For OMC: Compatible with V8 5.0L and 5.7L GM-based engines from 1993 onward.
| Brand | Model | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|
| Volvo Penta | V8 5.0L/305 CID | 4-Stroke | 1993+ | 501-MK | GM-based engines |
| Volvo Penta | V8 5.7L/350 CID | 4-Stroke | 1993+ | 501-MK | GM-based engines |
| OMC | V8 5.0L/305 CID | 4-Stroke | 1993+ | 501-MK | GM-based engines |
| OMC | V8 5.7L/350 CID | 4-Stroke | 1993+ | 501-MK | GM-based engines |
Technical Specs
- Product Type
- Exhaust Manifold Hardware Kit
- Installation
- Direct bolt-on
- Dimensions
- Height: 3.0 in, Width: 9.0 in, Length: 50.0 in
- Other Technical Attributes
- Made to exact OEM specifications
What’s in the Box
- 1 x Hardware Kit for MAR501 (501-MK)
- 1 x 160 degree Thermostat (3856961)
- 1 x Gasket (3852111)
- 1 x O-ring (3852071)
Installation Notes
- Disconnect the battery and allow the engine to cool completely.
- Drain the engine's cooling system according to the manufacturer's procedure.
- Carefully remove the old exhaust manifold hardware, gasket, and thermostat.
- Thoroughly clean the mounting surfaces on the engine block and manifold, ensuring they are free of old gasket material and debris.
- Install the new gasket, thermostat, and O-ring as specified by the engine service manual.
- Position the manifold and install the new hardware, tightening bolts in the correct sequence and to the manufacturer's torque specifications.
- Reconnect all hoses and related components.
- Refill the cooling system with the appropriate coolant.
- Start the engine and carefully check for any coolant or exhaust leaks at operating temperature.
Troubleshooting & FAQ
How do I know if this hardware kit fits my engine?
Verify your engine is a Volvo Penta or OMC V8 5.0L (305 CID) or 5.7L (350 CID) GM-based model from 1993 or newer. Cross-reference the part numbers listed in the Part Number Matrix with your existing parts to ensure compatibility.
What are the signs my manifold hardware is failing?
Common symptoms include visible coolant leaks around the manifold, engine overheating, rust or corrosion on bolts and fittings, and a damaged or leaking thermostat housing.
Does this kit include the exhaust manifold itself?
No, this is a hardware and gasket kit specifically for installing the MAR501 exhaust manifold. The manifold is sold separately.
Is it necessary to replace the thermostat with the hardware?
Yes. A new 160-degree thermostat is included and should always be installed with new hardware to ensure correct engine operating temperature and prevent overheating.
What is the recommended replacement interval?
There is no fixed interval. This hardware should be replaced whenever the exhaust manifold is serviced or replaced, or if you notice any signs of leaks, corrosion, or failure.
Can I reuse the old bolts when installing a new manifold?
It is strongly advised to use the new bolts and gaskets supplied in this kit. Old hardware can be fatigued or corroded, leading to improper sealing and potential 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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