Arco DR004 Distributor Rotor — MerCruiser Thunderbolt V8 5.0 / 5.7 / 7.4L
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
OEM-Grade Distributor Rotor for MerCruiser Thunderbolt V8 Engines
The Arco DR004 is a precision-fit replacement distributor rotor built for MerCruiser GM V8 engines equipped with the Thunderbolt Electronic Ignition system. Covering 5.0L, 5.7L, and 7.4L displacements, this rotor restores reliable spark distribution and is a staple component in any Thunderbolt ignition tune-up.
Compatible Applications
- MerCruiser GM V8 5.0L — Thunderbolt Electronic Ignition
- MerCruiser GM V8 5.7L — Thunderbolt Electronic Ignition
- MerCruiser GM V8 7.4L — Thunderbolt Electronic Ignition
Replaces OEM Part Numbers
- MerCruiser: 13524A1, 13524A3, 13524A5, 13524T1, 19405A3, 90576A2
- Sierra: 18-5431
- CDI Electronics: E65-0009
Parts Desk Insights
The DR004 is the correct rotor for MerCruiser Thunderbolt ignition systems — one of the most widely used ignition setups on V8 inboard boats from the 1980s through the mid-2000s. It’s a go-to tune-up component when diagnosing rough idle, hard starting, or ignition misfires on 5.7L and 7.4L engines. Always replace the rotor and distributor cap as a set. Pair with the Arco DC004 Distributor Cap or Arco DC007 Distributor Cap depending on your specific engine configuration for a complete ignition service.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.