Throttle Body Fuel Injector Kit – Fits Mercury/Mercruiser 575 SCi & 7.4L TBI (Replaces 853998A1)
Throttle Body Fuel Injector Kit – Fits Mercury/Mercruiser 575 SCi & 7.4L TBI (Replaces 853998A1) is backordered and will ship as soon as it is back in stock.
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Worry-free returns
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Delivery and Shipping
Delivery and Shipping
Free standard shipping on all orders under 1 KG
Throttle Body Fuel Injector Kit – Fits Mercury/Mercruiser 575 SCi &...
Product Details
This aftermarket Throttle Body Fuel Injector Kit is engineered for Mercury/Mercruiser 454-502 V8 engines, specifically covering 7.4L TBI and 575 SCi models manufactured between 1996 and 2002. It restores proper fuel delivery and engine performance for throttle body injection systems.
This kit serves as a direct replacement for Mercury part numbers 853998, 853998T, and 853998A1, as well as EMP part 1399-39404.
- Installation: Direct replacement fit for specified TBI models.
- Complete Set: Includes two injectors to service one V8 engine.
- Fuel Compatibility: Designed for use with gasoline.
Part Number Matrix
Use this matrix to confirm equivalent references across OEM and aftermarket.
| Brand | Part Number |
|---|---|
| Mercury | 853998 |
| Mercury | 853998T |
| Mercury | 853998A1 |
| EMP | 1399-39404 |
Engine & Model Compatibility
Confirm your engine model/year in the table below.
Compatibility for MerCruiser models is detailed below. Always verify your engine's serial number (Ser#) against the provided ranges to ensure an exact match.
| Brand | Model | Rated HP | Stroke | Years | OEM Part No. | Notes |
|---|---|---|---|---|---|---|
| MerCruiser | 7.4L TBI MIE (Gen VI) | 454 V8 | 4-Stroke | 1996–1997 | 853998A1 | Ser# 0F874815-0K999999 |
| MerCruiser | 7.4LX Bravo TBI (Gen VI) | 454 V8 | 4-Stroke | 1996–1997 | 853998A1 | Ser# 0F874815-0K999999 |
| MerCruiser | Race Stern Drive 575 | 4-Stroke | 2000 | 853998A1 | Ser# 4LF7215NH | |
| MerCruiser | Race Stern Drive 575 BRAVO | 4-Stroke | 2000–2001 | 853998A1 | Ser# 4LC2025MH, 4LE2025MH, 4LE2025PH | |
| MerCruiser | Race Stern Drive 575 SCI BRAVO | 4-Stroke | 2000–2002 | 853998A1 | Multiple serial ranges | |
| MerCruiser | Race Stern Drive 575 SCI VI DRYSUMP | 4-Stroke | 2001–2002 | 853998A1 | Ser# 4LF5015PH, 4LF7215PH, 4LF5015RH, 4LF7215RH |
Technical Specs
- Product Type
- Throttle Body Fuel Injector Kit
- Installation
- Direct replacement
- Fuel Type
- Gasoline
- Dimensions
- 6.0" x 1.0" x 6.0"
- Other Technical Attributes
- 2 injectors per kit
What’s in the Box
- 2 x Fuel Injector (replaces 853998A1)
Installation Notes
- Disconnect the battery and relieve all pressure from the fuel system according to your engine's service manual.
- Remove the flame arrestor and air horn assembly.
- Carefully unplug the electrical connectors from both fuel injectors.
- Remove the fuel meter cover and the injector retaining clips. Gently lift the old injectors out of the throttle body.
- Lightly lubricate the O-rings on the new injectors with clean engine oil.
- Press the new injectors firmly into their seats, ensuring they are properly aligned, and re-secure them with the retaining clips.
- Reassemble the fuel meter cover, reconnect electrical connectors, and reinstall the air horn and flame arrestor.
- Reconnect the battery, cycle the key to pressurize the system, and meticulously check for any fuel leaks before starting the engine.
Troubleshooting & FAQ
How do I know if this injector kit fits my engine?
This kit is designed for MerCruiser 7.4L TBI and 575 SCi engines (1996–2002). The most reliable way to confirm fitment is by matching your engine's serial number to the ranges listed in the compatibility table.
Is this a complete kit for one engine?
Yes, this kit includes two fuel injectors, which is the standard requirement for the V8 TBI (Throttle Body Injection) systems it services.
What are the signs of a failing fuel injector?
Common symptoms include rough idling, engine misfires, poor acceleration, increased fuel consumption, hesitation, or difficulty starting the engine. A fuel smell may also be present if an injector is leaking.
What is the difference between TBI and MPI injectors?
TBI (Throttle Body Injection) systems use one or two centrally located injectors in the throttle body, similar to a carburetor setup. MPI (Multi-Port Injection) systems use a separate injector for each cylinder, located on the intake manifold. This kit is for TBI systems only and is not compatible with MPI engines.
OEM vs. Aftermarket?
This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.
Shipping speed & cost?
We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.
Warranty & returns?
Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.
Safety & Important Info
- Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
- This is an aftermarket replacement, not an OEM component.
- Professional installation is recommended for safety and performance.
About Sea Sierra
- Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
- Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
- Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.
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