Volvo Penta Rear Engine Mount Lock Nut 3862657
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Volvo Penta 3862657 – Rear Engine Mount Lock Nut
- Part Number: 3862657
- Brand: Volvo Penta (OEM Genuine)
- Official Product Type: Lock Nut – Rear Engine Mount / Engine Mounting
- System: Engine Mounting
- Supersedes / Cross-Reference: No confirmed supersession trail; order by active number 3862657
- Weight: Approx. 0.05 lb (20 g)
- Kit Contents: Lock nut only – stud, washer, and mount rubber are serviced separately
The 3862657 is a genuine OEM Volvo Penta lock nut used in rear engine mount and engine mounting assemblies. It is the correct retaining fastener wherever the Volvo Penta parts diagram calls out part number 3862657 at the rear mount position. Small hardware like this is often overlooked during engine mount service — having the correct OEM nut on hand prevents reassembly delays and ensures the mount retains its specified torque properly.
Compatible Applications
- Volvo Penta gasoline and diesel inboard/sterndrive engines where 3862657 is specified at the rear engine mount position
- Confirm by engine serial number and Volvo Penta parts diagram before ordering — mount hardware varies by engine family, mount style, and hardware stack-up
Serial Number Notice: Volvo Penta engine mount hardware can differ across otherwise similar engine families. Adjacent nuts and fasteners at the same mount location may look identical but serve different positions. Always cross-reference your engine serial number and the correct mounting diagram before ordering.
When to Replace
Replace this lock nut when the original is thread-damaged, corroded, rounded, distorted, or no longer holds rear mount hardware securely. It is also good practice to replace the lock nut any time it has been fully removed during engine mount service — reused lock nuts can lose clamping force after repeated removal.
Service Interval
Inspect engine mount hardware annually or whenever the engine is removed. Replace any lock nut showing corrosion, thread damage, or distortion. Engine mounts are a safety-critical component — do not reuse hardware that shows wear.
Associated Service Parts
- Volvo Penta Engine Mounting 21112925 – Engine mount assembly
- Volvo Penta D3 Engine Mount Rubber Cushion 22230030 – Mount rubber isolator
- Volvo Penta Left-Hand Engine Bracket 21750952 – OEM D3 Diesel Mount bracket
Installation Notes
Inspect the related stud and washer at the rear mount position before reassembly. Torque to the specification shown in the Volvo Penta service manual for your engine model. Do not reuse a lock nut that has been previously torqued to spec — replacement is inexpensive insurance against mount failure.
Technical FAQ
Q: Can I substitute a standard metric lock nut of the same thread size?
A: Not recommended. OEM hardware is specified to meet Volvo Penta torque and retention requirements. Using a non-OEM substitute risks under-retention of the mount and potential engine movement under load.
Q: How do I confirm this is the right nut for my engine?
A: Look up your engine serial number in the Volvo Penta parts diagram for your specific engine and mounting group. The diagram will show part number 3862657 at its exact position.
Q: Is the stud or washer included?
A: No. This listing is for the lock nut only. The stud, washer, and mount rubber are serviced as separate parts.
Parts Desk Insights
Best Use Case: Ideal for customers doing a complete engine mount service who want to replace all hardware rather than reuse the original lock nuts. Often ordered alongside mount rubbers and brackets for a full mount refresh.
Common Issues: The most frequent mistake is assuming any similarly sized lock nut will work. Volvo Penta uses multiple fastener specifications across mount positions — always confirm part number 3862657 against your engine diagram before ordering. Customers also sometimes order this nut expecting it to come with the mount stud or washer; those are sold separately.
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.