Unique Products for Your Boat

Westerbeke Fit - Balmar Serpentine Pulley Kits

$619.99 $449.99
Please enter your engine model number.


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For Westerbeke Engine Models:
12C, 12D, 20B, 30B,18, 21A, 27A, 35B, 38B, 42B, 21, 13A, 27, 30C, 33, 44A, 44B, 55B, 55C, 55D, 56

If you have Westerbeke model not listed above please contact us before ordering.


If you have questions about fitment please contact Balmar before ordering. Balmar 1.360.435.6100

Pulley Bolts: The bolts supplied with these kits are representative of the particular engine the kit was modeled off of. These supplied bolts are not guaranteed to fit your particular engine. Engine manufacturers often change bore depth and this is beyond the control of Balmar. The bolts in the kit can potentially be either too long or too short. It is up to the purchaser to ensure the correct length bolts are used to hold the crank and waterpump pulleys.

Pulley Colors: Some pulley kits may include black anodized pulleys or a mix of black and blue pulleys. On slower moving engine kits the turnover can mean, that despite changing to blue many years ago, some black pulleys are still in inventory. This is considered normal.

Belt Length: Balmar tries very hard to supply the correct belts but variations in alternator brackets, even on the same engine models, mean the belts in the supplied kit may not be the correct length. Balmar will swap them out if this is the case but you will need to supply us with an accurate measurement and return the supplied belts to Balmar.

Alignment: While many of these kits will "drop-in" without too much fussing, this is not always a guarantee and some alignment may be necessary. Again slight engine variations mean a 100% perfect drop-in fit is not always possible.

The Pulley Kit:

These patented AltMount / Balmar serpentine pulley kits can drive an amazing amount of alternator horsepower. They utilize a J-10 belt design with ten ribs yielding tremendous grip with minimal to no belt dust..

These kits are specifically designed to fit select Westerbeke engine models and Balmar is growing the list every day. If you don't see your engine listed please contact Balmar or myself at the email address below.

Marine alternator upgrades using a single 1/2" or 3/8" drive belt are severely limited by the amount of power that can be handled by the belt. When increasing alternator size, using a serpentine belt considerably increases your total potential output and means little to no belt dust. Another benefit is that less belt tension is required to drive up to three times the HP. This means longer lasting water-pump bearings as well.

The kit comes with a set of anodized 10 groove pulleys which fit over the existing crankshaft pulley and a replacement water pump pulley. An alternator pulley is also in the kit. Kits include a J-10 serpentine belt, Loctite, Tef-Gel and a spare belt.

Alternators, regulators & temp sensors need to be purchased separately. If you order an alternator package from me, it will come with the appropriate pulley pre-installed on the alternator.

The photo above is representative only your kit may be slightly different.

Questions: compassmarineservices at gmail dot com