Sea-Doo Expansion Tank 276000086 – Spark GTI RXP RXT

Description

This aftermarket Sea-Doo expansion tank replaces part number 276000086. Designed for the cooling system, it can replace a damaged reservoir during repair. Before installation, compare the original part number, mounting points, and fitting arrangement with your reservoir. This is not a BRP genuine part.

Part number 276000086 is intended for the following four-stroke Rotax marine engines, subject to vehicle fitment:

• Rotax 1503 4-TEC: 1,494 cm³, three-cylinder, naturally aspirated and supercharged versions from 130 to 260 hp.
• Rotax 1630 ACE: 1,630 cm³, three-cylinder, versions from 130 to 350 hp.

Technical Specifications

• Corresponding OEM part number: 276000086.
• Type: expansion tank / coolant reservoir.
• Condition: new, aftermarket part with no brand indicated.
• Material: plastic.
• Packaging: one reservoir; cap, hoses, and mounting hardware not included.
• Weight: 350 g.
• Regulated substances: no substances of concern declared by the supplier.
• Installation: with the engine cold, according to the model's workshop manual; check connections, perform the required bleeding, and inspect for leaks.

Compatibility

Williams PWC

• WILLIAMS 435 Sportjet: 2015–2021, Rotax 1503 engine. View the technical sheet.
• WILLIAMS 400 Sportjet: 2015–2201. View the technical sheet.
• WILLIAMS 460 Sportjet: 2015–2021, Rotax 1503 engine. View the technical sheet.
• WILLIAMS 520 Sportjet: 2015–2021, Rotax 1503 engine. View the technical sheet.
• WILLIAMS 435 Sportjet, Sport version: from 2021.
• WILLIAMS 400 Sportjet: from 2021.
• WILLIAMS 460 Sportjet: from 2021.
• WILLIAMS 520 Sportjet: from 2021.

Sea-Doo Jet Skis

• GTX 4-TEC / GTX (130, 155, 170, 215, 230, 255, 260, 300 hp): from 2002 to present, depending on the version.
• RXP / RXP-X (215, 255, 260, 300, 325 hp): from 2004 to present, depending on the version.
• RXT / RXT-X (215, 255, 260, 300, 325 hp): from 2005 to present, depending on the version.
• GTI 4-TEC / GTI / GTI SE (130, 155, 170 hp): from 2006 to present, depending on the version.
• GTS 130: 2011–2019.
• GTR / GTR-X (215, 230, 300 hp): from 2012 to present, depending on the version.
• Spark / Spark Trixx (60, 90 hp): from 2014 to present, depending on the version.
• FishPro Scout, Sport and Trophy: from 2019 to present, depending on the version.

The indicated ranges cover several generations: they do not mean that every version or horsepower rating was offered throughout the entire period. Check the part number and reservoir configuration on your machine.

⚠️ Always check your serial number (VIN) and the original OEM part number before ordering to confirm exact compatibility with your model.

Why Replace the Expansion Tank?

A cracked reservoir or damaged fitting can cause coolant loss and compromise the operation of the cooling system. Similarly, engine overheating can cause the coolant to boil and, consequently, deform the tank. Repeated coolant level drops should be investigated: the tank is not necessarily the only cause.

• Visible crack or leak in the reservoir.
• Traces of coolant around the fittings or the filler neck.
• Broken fitting or damaged mounting point.
• Repeated coolant level drops requiring a system inspection.

Check the condition of the reservoir and its fittings during maintenance, with the engine cold. Replace it when a defect is confirmed, and inspect the hoses and cap before returning it to service.

See Also – Rotax 1503 and 1630 Engine Maintenance

NGK DCPR8E Spark Plug – Rotax 1503 and 1630 Sold individually or in packs of three, for the Sea-Doo and Williams applications listed in the spark plug data sheet. Check the model and year before ordering.

Rotax 1630 Oil Filter – 420956744 Common applications: RXP-X 300, RXT-X 300 and GTX 300 from 2016 to 2021, depending on the filter data sheet. Check your filter part number before ordering.