Tensioner Belt Pulley 3860079 for Volvo Penta 4.3 5.0 5.7 7.4 8.2 L Serpentine
Tensioner Belt Pulley 3860079 for Volvo Penta 4.3 5.0 5.7 7.4 8.2 L Serpentine
Product Overview
Serpentine belt tensioner pulley for the Volvo Penta sterndrives from 4.3 L to 8.2 L, the spring loaded roller that keeps the accessory belt tight. It replaces Volvo Penta 3860079, it fits the GLPEFS, GiPEFS, GXi and OSi models listed below, and one tensioner ships at 750 g with packaging. The pulley is supplied on its own, the serpentine belt is sold separately.
The front of these engines carries one flat multi-rib belt that drives the alternator, the circulating pump and the power steering pump. The tensioner is what holds that belt at the right load, and it is the part that fails first once the spring weakens or the bearing dries out.
A tensioner has two wear surfaces. The bearing inside the roller is what makes the noise, a chirp or a rumble that changes with engine speed. The spring and the arm are what make the belt slip, which shows up as a steering pump that gets heavy at idle or an alternator that stops charging when the engine is hot.
These are also replaced when the belt is changed as a pair. A new belt on a worn tensioner will run loose within a few hundred hours, and a new tensioner with a stretched belt will not hold its load either.
Fitment is by engine model code on the flame arrestor or the transom plate. The GXi and OSi codes were used from the late 1990s onward, and the GLPEFS and GiPEFS codes on the earlier carburetted and throttle body injected engines. Check the code against the table before ordering.
Specifications & Attributes
| Specification | Detail |
|---|---|
| Condition | New / New with tags |
| Type | Serpentine belt tensioner pulley |
| Volvo Penta Part Number | 3860079 |
| Material | Steel bracket, sealed roller bearing |
| Drive | Serpentine belt, front accessory drive |
| Engine Range | 4.3 L to 8.2 L Volvo Penta sterndrives |
| Displacement Range | 262 CID to 502 CID |
| Model Codes | GLPEFS, GiPEFS, GXi and OSi |
| Fits | 36 engine models listed in the table below |
| Belt | Not included, the serpentine belt is sold separately |
| Net Weight | 750 g including packaging |
| Packaging | Box |
| Quantity | 1 tensioner |
| Warranty | 3 year |
OEM Cross Reference
| Brand | Part Numbers |
|---|---|
| Volvo Penta | 3860079 |
Compatible Engines
| Engine | Displacement | Model Codes | Count |
|---|---|---|---|
| 4.3L | 262 CID | 4.3GLPEFS, 4.3GiPEFS, 4.3GXi-A, 4.3GXi-B, 4.3GXi-BF, 4.3OSi-B, 4.3GXi-C, 4.3GXi-CF, 4.3GXi-D, 4.3GXi-E, 4.3GXi-EF, 4.3OSi-E | 12 |
| 5.0L | 305 CID | 5.0GLPEFS, 5.0GiPEFS, 5.0GXi-A, 5.0GXi-B, 5.0GXi-BF, 5.0OSi-B, 5.0GXi-C, 5.0GXi-CF, 5.0GXi-D, 5.0GXi-E, 5.0GXi-EF, 5.0OSi-E | 12 |
| 5.7L | 350 CID | 5.7GSPEFS, 5.7Gi-A, 5.7GXi-A, 5.7Gi-C, 5.7Gi-CF, 5.7Gi-D, 5.7Gi-E, 5.7Gi-EF, 5.7GiI-E | 9 |
| 7.4L | 454 CID | 7.4GiPEFS, 7.4GSiPEFS | 2 |
| 8.2L | 502 CID | 8.2GSiPEFS | 1 |
What's Included
| Component | Detail | Qty |
|---|---|---|
| Belt tensioner with pulley | Volvo Penta 3860079, spring loaded arm and roller | 1 |
| Serpentine belt | Not included, the belt is sold separately | 0 |
| Mounting bolts | Not included, reuse the original bolts | 0 |
Key Features
| Feature | Detail |
|---|---|
| Direct replacement | Fits in place of Volvo Penta 3860079 |
| Sealed bearing | Roller bearing shielded against bilge water |
| Spring loaded arm | Holds the belt at the load the engine was built for |
| Five engine sizes | 4.3, 5.0, 5.7, 7.4 and 8.2 litre |
| 36 model codes | GLPEFS, GiPEFS, GXi and OSi variants listed in full |
| Belt sold separately | Fit a new belt at the same time |
Signs The Tensioner Needs Replacing
| What You See | What It Means | Action |
|---|---|---|
| Chirp or squeal that follows engine speed | Roller bearing dry or worn | Fit a new tensioner |
| Rumble from the front of the engine | Bearing collapsed | Fit a new tensioner |
| Belt slips when the steering is turned | Spring weak, belt not held at load | Fit a new tensioner |
| Belt edges fraying | Roller running out of line | Fit a new tensioner and belt |
| Tensioner arm does not spring back | Seized pivot | Fit a new tensioner |
| New belt goes slack quickly | Old tensioner cannot take up the stretch | Fit a new tensioner |
Fitting Notes
| Step | Action |
|---|---|
| 1 | Check the engine model code against the table above |
| 2 | Disconnect the battery and take a photo of the belt routing before it comes off |
| 3 | Release the tensioner with the correct tool and slip the belt off |
| 4 | Take the mounting bolts out and lift the old tensioner away |
| 5 | Clean the mounting face on the block and check the threads |
| 6 | Fit the new tensioner and torque the bolts to the manual figure |
| 7 | Fit a new belt following the routing you photographed |
| 8 | Run the engine and watch the belt track and the tensioner arm move before the boat goes back in the water |
Condition & Warranty
| Item | Detail |
|---|---|
| Condition | New / New with tags |
| Warranty | 3 year |
| Packaging | Box |
Before You Buy
- Replaces Volvo Penta 3860079
- Fits the Volvo Penta sterndrives from 4.3 L to 8.2 L
- Covers the GLPEFS, GiPEFS, GXi and OSi model codes
- 36 engine models listed in the table above
- Five engine sizes from 4.3 to 8.2 litre
- The serpentine belt is not included, it is sold separately
- One tensioner, mounting bolts not included
- 750 g with packaging
- 30-Day Easy Returns
- Free Worldwide Shipping
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Boat Owners' Review
Before You Buy
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