Sierra 18-5273 Medium Tune Up Kit for MerCruiser 500 Bulldog 540 V-8 and 800 SC 572 V-8 Engines

The Sierra 18-5273 Medium Tune Up Kit is built for GM V-8 engines equipped with Thunderbolt IV and V HEI ignition systems, and is designed for use alongside the Sierra 18-5470 Thunderbolt HEI distributor. It covers the ignition-side components needed to service a marine V-8 during a routine tune-up, engineered to meet the demands of high-horsepower engines operating in the marine environment.

This kit is application-specific to two MerCruiser inboard configurations: the 500 Bulldog 540 cid V-8 built between 1990 and 2001 (serial number range C577003 through M050281), and the 800 SC 572 cid V-8 built between 1993 and 1998 (serial number D763836 and up). Confirming your engine's serial number against these ranges before ordering will ensure you get the correct tune-up components for your powerhead.

Sierra manufactures this kit to meet or exceed the performance of the original equipment part it replaces, and supplies OEM engine manufacturers and boat builders with parts daily, so build quality and fit are held to the same standard used in original production. The kit ships as a single unit count, ready to install as part of a standard ignition service interval.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-5273
• Product Type: Tune Up Kit
• Unit Count: 1
• Weight: 0.77 pounds
• UPC: 808282113070
• GTIN: 00808282113070
• Ignition System Compatibility: GM V-8 engines with Thunderbolt IV and V HEI ignitions
• Companion Distributor: Use with Sierra 18-5470 Thunderbolt HEI distributor
• Fitment - MerCruiser 500 Bulldog 540 cid V-8: Model years 1990-2001, serial number range C577003 to M050281
• Fitment - MerCruiser 800 SC 572 cid V-8: Model years 1993-1998, serial number D763836 and up

Fitment

• MerCruiser 500 Bulldog 540 cid V-8, model years 1990-2001, serial number C577003 - M050281
• MerCruiser 800 SC 572 cid V-8, model years 1993-1998, serial number D763836 and up

Frequently Asked Questions

What engines does the Sierra 18-5273 tune up kit fit? The Sierra 18-5273 Medium Tune Up Kit fits the MerCruiser 500 Bulldog 540 cid V-8 (model years 1990-2001, serial number range C577003 to M050281) and the MerCruiser 800 SC 572 cid V-8 (model years 1993-1998, serial number D763836 and up).

Does this kit work with the Thunderbolt HEI ignition? Yes, the 18-5273 kit is designed for GM V-8 engines running Thunderbolt IV and V HEI ignition systems.

What distributor should I use with the 18-5273 kit? This tune up kit is intended for use with the Sierra 18-5470 Thunderbolt HEI distributor.

How much does the Sierra 18-5273 tune up kit weigh? The 18-5273 Medium Tune Up Kit weighs 0.77 pounds.

How many units come in the 18-5273 kit? The kit ships as a single unit count (1) under Sierra part number 18-5273.

Is the Sierra 18-5273 a genuine Sierra part or aftermarket? It is a Sierra-manufactured marine part, engineered to meet or exceed the performance of the original equipment component it replaces, part number 18-5273.

Will this kit work on any GM V-8 marine engine? No, the 18-5273 kit is matched to specific MerCruiser applications: the 500 Bulldog 540 cid V-8 and 800 SC 572 cid V-8 within the serial number ranges listed for those models, not GM V-8 engines generally.

How do I confirm my engine matches the 18-5273 kit before ordering? Check your MerCruiser engine's serial number against the ranges for the 18-5273 kit: C577003 to M050281 for the 500 Bulldog 540 cid V-8, or D763836 and up for the 800 SC 572 cid V-8.

What is the UPC for the Sierra 18-5273 tune up kit? The UPC for the Sierra 18-5273 Medium Tune Up Kit is 808282113070.

Why choose the Sierra 18-5273 over a generic tune up kit? Sierra supplies OEM engine manufacturers and boat builders with parts daily and builds the 18-5273 kit to meet or exceed the original equipment part it replaces, giving it OEM-level fit and performance for the specified MerCruiser applications.

Is the 18-5273 kit a full engine tune up kit or ignition-specific? The 18-5273 is a Medium Tune Up Kit focused on the ignition-side service items for GM V-8 engines with Thunderbolt IV and V HEI ignitions.