13524T1 Mercruiser Rotor | Genuine Used Part

🔧 Product Description

Genuine Used Mercury MerCruiser Thunderbolt V8 Distributor Rotor - Part Number: 13524T1

A genuine pre-owned Mercury MerCruiser distributor rotor for selected marinised General Motors V8 engines equipped with Thunderbolt IV or Thunderbolt V electronic ignition.

The rotor mounts to the distributor shaft and directs high-voltage ignition current from the centre terminal of the distributor cap to each cylinder terminal in firing order.

⚙️ Key Features

• Genuine Mercury MerCruiser used rotor

• Correct current OEM part number 13524T1

• Fits compatible GM V8 Thunderbolt IV and V distributors

• Used with eight-cylinder distributor cap assemblies

• Sierra, CDI, GLM, Mallory and Recmar replacements available

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 13524A1 - Earlier rotor assembly

• 13524A3 - Earlier rotor assembly

• 13524A5 - Superseded by 13524T1

• 13524T1 - Current Mercury service reference

OEM / Related Numbers:

• 13524T1

• 13524A1

• 13524A3

• 13524A5

• 13524B1

• 13524B5

• 19405A3

• 90576A2

• 19021A2

• 42862

• Related distributor cap: 805759T1 / 805759Q01

Aftermarket / Verified Equivalents:

• Sierra: 18-5431

• CDI Electronics: E65-0009

• GLM: 71080

• Mallory: 9-29200

• WSM: 371-250

• Recmar: REC13524A1

• ARCO replacement rotor application

🚤 Compatibility

Commonly used on:

• MerCruiser GM V8 petrol marine engines

• Thunderbolt IV ignition systems

• Thunderbolt V ignition systems

• Sterndrive and inboard installations

Typically suits selected:

• 5.0L / 305 CID V8

• 5.7L / 350 CID V8

• 7.4L / 454 CID V8

• Other MerCruiser V8 engines using the matching Thunderbolt distributor

• Representative Application Period: Approximately 1984-2013

• Ignition Type: Electronic distributor ignition

Important fitment note:

• Confirm the original distributor type and rotor shape.

• Similar Delco and Thunderbolt distributor parts are not automatically interchangeable.

• Inspect the cap and ignition sensor at the same time.

🔌 Function

The rotor receives high voltage from the distributor-cap centre contact and directs it to each spark-plug lead terminal as it rotates.

Common signs of wear or failure:

• Engine misfires under load

• Difficult starting

• No spark from the distributor

• Carbon tracking

• Burnt rotor tip

• Cracked insulation

• Excessive corrosion

• Loose fit on the distributor shaft

• Spark cross-fire inside the cap

Recommended checks before installation:

• Inspect the rotor tip and centre contact

• Check for cracks and carbon tracking

• Inspect the distributor cap terminals

• Confirm the rotor fits the shaft securely

• Check shaft and bush wear

• Verify ignition timing after reassembly

📦 Condition

• Genuine Mercury MerCruiser used part

• Pre-owned ignition component

• Contact wear and cosmetic marks may be present

• Inspect electrically and visually before installation

• Supplied in protective or equivalent packaging