803918T Carburetor Prime Starter Assembly
803918T Carburetor Prime Starter Assembly is backordered and will ship as soon as it is back in stock.
Need help checking fitment?
Need help checking fitment?
Send us the product link, your engine brand, full model and serial number, and the reference on your original part. Include the year if known.
Shipping & delivery
Shipping & delivery
Have a delivery question? Include the part reference, quantity, destination country and postal code so we can check the shipping details for your order.
Returns & warranty support
Returns & warranty support
For help with an order or product issue, send your order number, part reference and a description of the issue. Include photos where relevant.
Product Overview
XR MARINE ยท CARBURETORS & REPAIR KITS
803918T Carburetor Prime Starter Assembly
This XR Marine item is a single marine carburetor component referenced under Mercury Mariner part number 803918T and classified in the Carburetor Prime Starter Assembly category. It is supplied as an individual part rather than a multi-piece repair kit.
Because no specific engine models, horsepower ratings, or model years are listed on this page, always verify part number 803918T against the official parts catalog for your exact engine model and serial number, and confirm the exact component configuration with XR Marine before ordering.
Product Specifications
Key product details for identification and comparison.
Fitment
The 803918T Carburetor Prime Starter Assembly from XR Marine requires direct part-number verification against your engine's official parts catalog before ordering.
Match the full model and serial number on your engine identification plate to your official parts diagram, compare the complete OEM reference number 803918T including its suffix, and follow any serial-number or carburetor version restrictions listed in your manual. The Mercury Mariner brand association or engine horsepower alone cannot confirm compatibility.
Fitment to Confirm
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Brand: Mercury Mariner | OEM Reference: 803918T | Restriction: Confirm the required part number against the parts catalog for the exact engine model and serial number before ordering; the Mercury Mariner label alone does not establish compatibility.? Confirm fitment
OEM & Part Number References
Use the complete reference number, including its suffix, when comparing parts. Reference numbers do not confirm that every version is interchangeable.
Installation Guide
General installation overview. Follow the service manual for your exact engine and carburetor configuration. Fuel-system work requires the appropriate skills and precautions.
- Verify Part Number and Component Identity: Before starting work, check your engine identification plate and parts catalog to confirm that 803918T matches your required assembly, and inspect the supplied part against your existing component.
- Prepare a Safe Workspace: Shut off the engine, allow it to cool completely, disconnect the battery or ignition leads, and isolate the fuel supply as instructed in your service manual. Work in a well-ventilated area away from open flames or sparks.
- Document Existing Connections: Take clear photos or notes of all fuel hoses, linkages, electrical leads (if applicable to a prime starter unit), and mounting hardware orientation before disassembly.
- Remove the Existing Component: Follow your service manual to carefully relieve any residual fuel pressure and remove the original carburetor or prime starter component without damaging mating surfaces or adjacent linkages.
- Compare Mounting and Interfaces: Place the existing part and the replacement side by side to verify that mounting points, passages, ports, and connectors match exactly before installation.
- Install and Reconnect: Position the component and secure all fasteners, hoses, linkages, and connections strictly according to the sequence and specifications in your engine service manual.
- Inspect for Fuel Leaks and Binding: Restore the fuel supply and check thoroughly for any fuel seepage around seals and fittings. Confirm that all throttle, choke, or starter mechanisms move smoothly without binding.
- Test with Proper Cooling Water Supply: Supply cooling water to the engine as specified by the manufacturer before starting. Perform any manual-specified checks or adjustments, and shut the engine down immediately if leaks or abnormal operation occur.
Before You Order
A careful fitment check helps you choose the right part the first time.
- Match the full engine model designation on the identification plate.
- Verify your engine serial number and exact model configuration against the official parts catalog to confirm whether 803918T is specified for your unit.
- Compare the complete OEM reference number, including its suffix. Horsepower or appearance alone is not enough.
- Confirm the package contents and the quantity needed for your repair.
- Note that this listing is not a repair kit; contact XR Marine if you need to clarify whether you require a complete carburetor assembly or a prime starter assembly.
Need help checking fitment? Have your engine identification details, the existing part number and clear photos ready when you contact XR Marine.
Ask XR Marine About FitmentWhy XR Marine
Carburetors are our focus. Fitment comes first.
XR Marine specializes in marine carburetors, carburetor repair kits and the related parts needed for these repairs. We keep our focus on this product line so that product information stays centered on the details that matter: engine applications, complete part-number references and what is included.
Use our individual fitment entries and part references to compare your application, then contact XR Marine if you need help before ordering.
Shipping
Free shipping on all orders. No minimum order value.
For questions about delivery to your destination or delivery timing, contact XR Marine before placing your order.
Contact XR Marine About ShippingLifetime Warranty
XR Marine provides lifetime warranty coverage for product quality defects. Normal wear and tear is excluded.
- Covered: product quality defects.
- Not covered: normal wear and tear.
Contact XR Marine for warranty assistance. Having your order details and a description of the issue available can help us understand your request.
Contact XR Marine About WarrantyFrequently Asked Questions
Answers to common questions about this product and its application.
How can I verify if part number 803918T fits my Mercury Mariner engine?
Locate the full model designation and serial number on your engine's identification plate and look up the carburetor diagram in the official Mercury Mariner parts catalog. Only order if your catalog specifically calls for 803918T, as the Mercury Mariner brand reference alone does not establish fitment.
Why is this item referenced under both Carburetor and Carburetor Prime Starter Assembly?
Our source catalog lists this part as a Carburetor and also classifies it under Carburetor Prime Starter Assembly. Because the exact component configuration is not confirmed on this page, please contact XR Marine with your engine details and photos of your existing part before ordering.
Is 803918T a carburetor repair kit?
No. This product is confirmed not to be a repair kit. If you need to know the exact supplied pieces or whether any mounting hardware is included, please reach out to XR Marine prior to purchase.
Does the "T" suffix in 803918T matter when comparing part numbers?
Yes. Always compare the complete OEM reference number including its suffix (803918T). Different suffixes or base numbers can represent different carburetor configurations or prime starter versions that may not be interchangeable.
Is this a genuine Mercury Mariner OEM part?
No. This part is sold under the XR Marine brand. Mercury Mariner and 803918T are used strictly as OEM reference information to help you identify and compare the component.
What shipping and warranty coverage apply to this order?
XR Marine offers free shipping on all orders with no minimum order value, along with a lifetime warranty covering product quality defects (normal wear and tear is excluded).
Payment & Security
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