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Mercury Belt Tensioner Assembly
Mercury 8M0164060 Tensioner Assembly
The Mercury 8M0164060 Tensioner Assembly is used in the belt drive system to help maintain proper belt tension and pulley alignment. A worn tensioner or pulley can lead to belt noise, slipping, uneven belt wear, or charging and accessory drive issues.
When replacing this tensioner assembly, it is usually a good idea to inspect and replace the belt at the same time. The related Mercury 8M0159595 belt is linked below.
Compatible Applications
| Engine / Application | Part Number |
|---|---|
| Mercury 450R V8 belt drive system | 8M0164060 |
Verify your engine serial number and original tensioner part number before ordering. Mercury belt drive components can vary by model and serial range. The related belt listed by Pro Marine is identified as fitting Mercury 450R V8.
OEM & Cross Reference Numbers
| Type | Part Number |
|---|---|
| Mercury OEM | 8M0164060 |
Related Belt Replacement
Mercury 8M0159595 Belt - Mercury 450R V8
It is common to replace the belt when servicing the tensioner or pulley. A worn belt can cause slipping, noise, poor charging performance, or premature wear on the new tensioner assembly.
What This Part is Used For
The belt tensioner assembly keeps proper tension on the engine belt so the belt can drive related engine accessories correctly. If the tensioner weakens, binds, or the pulley wears out, the belt may slip, squeal, track incorrectly, or wear faster than normal.
Replacing the tensioner assembly helps restore proper belt control. Because the belt rides directly on the pulley system, replacing the belt during the same service is often recommended.
Key Features and Benefits
- Mercury OEM tensioner assembly
- Part number 8M0164060
- Helps maintain correct belt tension
- Supports proper belt tracking and accessory drive operation
- Useful when repairing belt noise, slipping, or pulley wear
- Related Mercury 8M0159595 belt linked above
- Recommended to inspect or replace the belt during tensioner service
Common Signs of a Worn Tensioner or Belt
| Symptom | Possible Cause |
|---|---|
| Belt squeal or chirping | Weak tensioner, worn pulley, glazed belt, or misalignment |
| Visible belt wear | Pulley wear, improper tracking, or old belt |
| Belt slipping | Loss of tension or worn belt surface |
| Pulley noise | Worn bearing or damaged tensioner pulley |
FAQ
What is the OEM number for this tensioner?
The OEM part number is 8M0164060.
Should I replace the belt when replacing the tensioner?
Yes, it is usually recommended to inspect and replace the belt when servicing
the tensioner or pulley, especially if the belt shows wear, glazing, cracking,
noise, or slipping.
Which belt goes with this tensioner?
The related belt is Mercury 8M0159595, linked above.
What does the tensioner assembly do?
It keeps the engine belt under proper tension so the belt can drive related
engine accessories correctly.
Can a bad tensioner damage a new belt?
Yes. A worn or misaligned tensioner can cause premature belt wear, belt noise,
or belt tracking problems.
Do I need to verify fitment?
Yes. Always verify your engine serial number and original part number before
ordering Mercury belt drive components.
Dealer Discounts & Store Policies
Dealer / Marine Industry Discounts
Are you a marine dealer, technician, boat builder, or industry professional? We offer dealer pricing for qualified marine businesses.
Shipping Policy
- Free shipping on orders over $100 continental U.S.
- Orders ship via UPS, USPS, and FedEx.
- Orders received before 5:30 PM EST ship the same business day.
- Typical delivery time is 1-5 business days.
30-Day Return Policy
- Returns accepted within 30 days of delivery.
- Parts must be new, unused, and in original packaging.
- Installed parts are not returnable.
- Return authorization is required before sending items back.
Need help with a return or order question?
Contact Us
Phone: 941-721-3000
Searchable Terms
8M0164060, Mercury 8M0164060, Mercury tensioner assembly, Mercury belt tensioner, Mercury pulley tensioner, Mercury 450R tensioner, Mercury 450R V8 tensioner, Mercury Racing 450R tensioner, Mercury belt drive tensioner, outboard belt tensioner, Mercury belt pulley, 8M0159595, Mercury 8M0159595, Mercury 450R V8 belt, Mercury belt replacement, tensioner and belt replacement
8M6003035
885349500
8M0218433
8M0159115
8M0238746
Electrical / Charging
Genuine Mercury Alternator Belt - 8M0178243
OEM Mercury Alternator Drive Belt for 350-425HP V10 and 500-600HP V12 outboards.
Ensures reliable alternator operation and proper charging of the electrical system.
Compatible Applications
| Brand | Engine | Horsepower | Fitment Note |
|---|---|---|---|
| Mercury | V10 | 350-425 HP | Alternator Drive Belt |
| Mercury | V12 | 500-600 HP | Alternator Drive Belt |
Important Fitment Note
Always confirm compatibility using your engine serial number before ordering.
OEM & Cross Reference Numbers
| OEM | 8M0178243 |
What This Part Is Used For
This belt drives the alternator on Mercury high-horsepower V10 and V12 outboards.
Replacing a worn belt prevents charging system failure and accessory drive slippage.
Key Features and Benefits
- Genuine Mercury OEM quality
- Designed for high-horsepower V10 & V12 engines
- High strength and heat resistance
- Ensures reliable electrical system performance
FAQ
What engines does this belt fit?
Mercury 350-425HP V10 and 500-600HP V12 outboards.
How often should the alternator belt be replaced?
Inspect at regular service intervals and replace if cracked, glazed, or stretched.
Dealer Discounts & Store Policies
Dealer / Marine Industry Discounts
Are you a marine dealer, technician, boat builder, or industry professional? We offer dealer pricing for qualified marine businesses.
Shipping Policy
- Free shipping on orders over $100 continental U.S.
- Orders ship via UPS, USPS, and FedEx.
- Orders received before 5:30 PM EST ship the same business day.
- Typical delivery time is 1-5 business days.
30-Day Return Policy
- Returns accepted within 30 days of delivery.
- Parts must be new, unused, and in original packaging.
- Installed parts are not returnable.
- Return authorization is required before sending items back.
Need help with a return or order question?
Contact Us
Phone: 941-721-3000
Searchable Terms
Mercury V10 alternator belt, Mercury V12 alternator belt, 8M0178243, 350-425HP V10 belt, 500-600HP V12 belt
Searchable Part Numbers
8M0178243
8M0235013
88107
88107A5
9-15301
827509A1
827509A10
827509A4
827509A7
827509A9
827509T7
5287A1
5287A2
5287A3
5287A4
6222A1
6222A10
6222A4
6222A6
6222A8
899883229
9-25106
821889A29
821889A40
821889A42
821889A50
821889A51