Mercury 807730T Crankshaft Pulley – MerCruiser GM V6 & V8 Serpentine
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Mercury 807730T – Crankshaft Accessory-Drive Pulley | MerCruiser GM V6 & V8 Serpentine Belt
Part Number: 807730T
Brand: Mercury Marine
Type: Crankshaft Accessory-Drive Pulley
System: Serpentine Belt Accessory Drive
Position: Crankshaft / Harmonic Balancer Assembly
GTIN: 745061288119
Genuine Mercury Marine replacement crankshaft pulley for selected 1998-and-newer MerCruiser sterndrive and inboard engines equipped with a serpentine accessory belt. The 807730T mounts directly at the crankshaft/harmonic balancer assembly and drives the serpentine belt that powers the alternator, power steering pump, seawater pump, and other accessories.
Compatible Applications
- GM-based V6 MerCruiser – 1998 and newer, serpentine belt configurations
- 5.0L / 305 CID V8 MerCruiser – selected configurations
- 5.7L / 350 CID V8 MerCruiser – includes 350 MAG, 350 MAG EFI, 350 MAG MPI families
- 6.2L / 377 CID V8 MerCruiser – selected configurations
- Selected sterndrive and inboard configurations using GM-based engines with serpentine belt drive
Serial Number Notice: Confirm your engine serial number and accessory-drive layout before ordering. Similar GM-based MerCruiser engines may use different crankshaft pulleys or belt configurations depending on model year, cooling system, and accessory arrangement.
When to Replace
- Pulley is bent, cracked, or damaged at the belt grooves
- Heavy corrosion affecting the pulley surface or belt contact area
- Belt misalignment or unusual accessory-drive vibration traced to the crankshaft pulley
- Any time the harmonic balancer is removed or replaced
When replacing the crankshaft pulley, also inspect the harmonic balancer, serpentine belt, belt tensioner, and all adjacent driven pulleys.
Installation Notes
- Disconnect battery power before beginning any accessory-drive service
- Note the existing serpentine-belt routing before removal
- Inspect the harmonic balancer and mounting hardware for wear or damage
- Inspect the belt, tensioner, and all driven pulleys — replace any worn components at the same time
- Install the crankshaft pulley per the applicable MerCruiser service procedure
- Verify belt alignment and tension after installation before starting the engine
Part Numbers & Cross-Reference
- Mercury Marine: 807730T
- GTIN: 745061288119
Related Serpentine Drive Components
- Water Pump Drive Pulley – 8M0153706 (replaces 807729T)
- Power Steering Pump Pulley – 8M0150723
- Seawater Pump Pulley – 8M0150724
- Serpentine Belt & Pulley Kit – 8M0150824
Parts Desk Insights
The critical fitment check for 807730T is confirming a GM-based MerCruiser V6 or V8 with serpentine belt drive — earlier engines used a V-belt arrangement and require a different pulley. The most common customer mistake is ordering without verifying the engine serial number and belt type. If you're already in the accessory drive for this replacement, it's a smart opportunity to inspect the full serpentine system — the Serpentine Belt & Pulley Kit 8M0150824 covers the most common service items in one order. The related water pump pulley 807729T has been superseded by 8M0153706 if that part is also needed.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 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.