Manifolds & Accessories - OSCO

2- Groove Billet Crankshaft Pulley For Big Block Chevy
Your Price:
$78.99

Big Block Chevy 2-Groove Billet Crankshaft Pulley

421-843

2-Groove Billet Crankshaft Pulley For Big Block Chevy

  • Machined from 6061-T6 billet aluminum. 
  • Set up for a Mercury replacement with deeper v-groove. 
  • Comes highly polished.
  • Diameter of 6.5"
  • Pilot Hole is 1-1/8"

Small Block Chevy 3 V-Groove Crank Pulley
Your Price:
$72.99

Big Block Chevy Billet Small Diameter Crank Pulley

740-64201

Big Block Chevy Billet Small Diameter Crank Pulley - Machined from solid billets of the highest-grade aircraft aluminum for maximum durability and feature deep, precision-machined groove to ensure belt retention, even during extreme changes in engine rpm. These pulleys have a black anodized hard-coat for extended life and corrosion resistance . Diameter 5.250".


Big Block Chevy Generation 4 Sea Pump Pulley
Your Price:
$119.99

Big Block Chevy Generation 4 Sea Pump Pulley

625-4024

Big Block Chevy Generation 4 Sea Pump Pulley

All Hardin Marine sea pump pulleys for Gen 4 & 5 V-groove belts use a mandrel on the pump, then the pulley bolts to the mandrel. Some manufacturers sell you a press-on pulley, these usually work themselves off.  This needs a mandrel to mount.

Pulley diameter of 6.5".


Billet Serpentine Pulley Kit
Your Price:
$799.99

Billet 454/502 Mercury Serpentine Pulley Kit

421-301K

Billet 454/502 Mercury Serpentine Pulley Kit

This kit comes with:

  • 1 - Crankshaft pulley
  • 1 - Circulating pump pulley
  • 1 - Sea pump pulley
  • 1 - Power steering pulley
  • 1 - Alternator pulley
  • 1 - Idler pulley

All pulleys are CNC machined and are tumble polished (semi-polished, satin finish).
NOTE: This kit will not retrofit V-Belt Pulley Systems to Serpentine. It is to replace existing Serpentine setups only!


Billet V-Groove Engine Pulley Kit For Mercury Big Block Chevy Generation 5 & 6

Your Price:
$487.99

This Part has options, please click the button below to order.

Billet V-Groove Engine Pulley Kit For Mercury Big Block Chevy Generation 5 & 6

421-202K

Billet V-Groove Engine Pulley Kit For Mercury Big Block Chevy Generation 5 & 6

This kit includes:

  • (1) 3-groove crankshaft front pulley
  • (1) Sea pump pulley
  • (1) Power steering pulley with mandrel
  • (1) Alternator Pulley. Note: Please indicate what shaft style your alternator has for the correct pulley.

At Hardin Marine we manufacture the finest high speed deep groove engine pulleys available. Each pulley is manufactured from 6061-T6 billet aluminum using Tru-Trac technology. Tru-Trac allows the V-belt to ride deep in the belt groove for maximum belt contact. Both the power steering and sea pump pulley use mandrel mounting features that protect the pulley from undue shaft heat. The most common cause for failure in lesser quality pulleys is caused from heat transferring to the pulley releasing from the shaft causing undue damage and safety hazards. All Hardin Marine shaft mount style pulleys use mandrels assuring you the best money can buy.


Mando Alternator Pulley
Your Price:
$159.99

Delco Alternator Pulley

421-216

Delco Alternator Pulley - Straight Shaft

Hardin Marine has the correct billet alternator pulley for your Delco alternator. Just slide yours off and replace it with Hardin polished billet pulley.

Fits a straight shaft that is .669" in diameter

Please Note: the pulley overall dia. is 5", the belt portion is 3-1/4" outer dia.


Double Groove Alternator Pulley
Your Price:
$59.95

Double Groove V-Belt Alternator Pulley

421-219

Double Groove V-Belt Alternator Pulley for use on alternators with round pulley shaft. 2-5/8" OD.


Gen 4 Serpentine Pulley 6-Rib
Your Price:
$169.99

Gen 4 Serpentine Pulley 6-Rib

625-4055

Gen 4 Serpentine Pulley 6-Rib (Needs Mandrel to Mount)

All Hardin Marine Sea pump pulleys for Gen 4 & 5 v-groove bolt use a mandrel on the pump, then the pulley bolts to the mandrel. Some manufacturers sell you a press-on pulley, these usually work themselves off.

Note:  Mandrel Sold Separately.


Gen 7 496 Sea Pump Pulley
Your Price:
$139.99

Gen 7 496 Sea Pump Pulley and Mandrel Kit - Black

625-4278

Replacement 496 Sea Pump Pulley and Mandrel Kit

This billet pulley is designed as a replacement for popular MerCruiser applications. Will fit stock MerCruiser or Hardin Gen 7 Pump. For 496 applications only. Includes mandrel and bolts. This kit includes #13 - #16 on the Gen 7 Sea Pump Breakdown.

Hub, Xover P/S Pump-Pulley
Your Price:
$48.99

Hub, Xover P/S Pump-Pulley

625-8107

Hub, Xover P/S Pump-Pulley

Power steering pump mandrel. Fits late model power steering pumps with plastic reservoir, and krc style pumps, both with a 5/8 shaft.


Mandrel For Power Steering Pulley
Your Price:
$36.99

Mandrel For Power Steering Pulley

421-207M

Mandrel For Power Steering Pulley

This Mandrel presses on the pumps drive shaft and allows for easy bolting up of the 421-207 pulley. 

Fits saginaw style power steering pumps with 3/4 dia. shafts.

Mandrel For Sea Pump Pulley
Your Price:
$36.99

Mandrel For Sea Pump Pulley

421-205M

Mandrel For Sea Pump Pulley


Mercury 600/662/700 Upper Blower Pulley 3.50
Starting From:
$299.99
This Part has options, please click the button below to order.

Mercury 600 / 662 / 700 Upper Blower Pulley

625-822 + Option(s)

Mercury 600/662/700 Upper Blower Pulley

Billet aluminum blower pulley, 3.25" or 3.50" diameter.

S/C BBC 3 Groove Crank Pulley
Your Price:
$194.99

S/C BBC 3 Groove Crank Pulley

421-218

S/C BBC 3 Groove Crank Pulley

  • BBC 3grv crank pulley for Supercharger application.
  • Will fit either 3 or 6 bolt damper.
  • 5.40 outside diameter by 2.350 thick

Small Diameter Alternator Pulley
Your Price:
$59.99

Small Diameter Alternator Pulley

625-3146

Small Diameter Alternator Pulley

This new small diameter alternator pulley (1-3/4" O.D) is designed for use on Delco round shaft style alternators in applications requiring aboost in or higher voltage rate from the charging system at an idle. (Example) at 700 RPM of the engine spinning the alternator at 2135 RPM you can reach the optimum RPM range of an alternators charging mode.This has become a simple fix for engines with extensive electrical system draw.that are suffering from not enough charging system output at low rpm.