MerCruiser Rear Engine Mounting Bolt Kit – Fits Alpha One and Bravo Drives (Replaces 10-97934A1)

$17.99 $28.00

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Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This MerCruiser Rear Engine Mounting Bolt Kit is designed for stern drive rear engine mount applications. It is compatible with MerCruiser R, MR, Alpha One, Alpha One Gen II, and Bravo stern drives, providing a secure and reliable transom mount connection.

It serves as a direct interchange for Mercury/Quicksilver 10-97934A1, Sierra 18-2141, and GLM 21810.

Designed for MerCruiser stern drive transom mount applications.
Includes all necessary hardware for one rear mounting point; two kits are typically required per engine.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand	Part Number
Mercury/Quicksilver	10-97934A1
Sierra	18-2141
GLM	21810

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Brand	Model	OEM Part No.
MerCruiser	R Drive	10-97934A1
MerCruiser	MR Drive	10-97934A1
MerCruiser	Alpha One	10-97934A1
MerCruiser	Alpha One Gen II	10-97934A1
MerCruiser	Bravo Drives	10-97934A1

Technical Specs

Product Type: Engine Mounting Bolt Kit
Installation: Stern Drive Rear Engine Mount
Application: For MerCruiser stern drive transom mount applications
Dimensions: 14.5" L x 1.5" W x 4.0" H
Weight: 0.44 lb (0.2 kg)
Warranty: 1 Year

What’s in the Box

1 x Bolt (10-97934)
1 x Washer (12-35777)
1 x Lockwasher (13-33734)
1 x Spacer (23-99299)
1 x Nut (11-863332)
1 x Fibre Washer (12-32834)

Installation Notes

Ensure the engine is safely and properly supported before beginning work.
Remove the old rear engine mounting bolts and hardware. Note that two kits are typically needed for a complete engine installation.
Thoroughly clean and inspect the transom mounting surfaces for any signs of wear, corrosion, or damage.
Install the new hardware components in the correct order as specified by your engine's service manual.
Tighten and torque the lock nut to the manufacturer's recommended specification to ensure a secure fit.
Always consult your official MerCruiser service manual for detailed procedures and precise torque values.

Troubleshooting & FAQ

How many kits are required for one engine?

Most MerCruiser stern drive applications require two of these kits—one for each of the two rear engine mounts. Please verify the requirement for your specific setup.

Is this kit compatible with my specific MerCruiser model?

This kit fits a broad range of MerCruiser stern drives, including the R, MR, Alpha One (Gen I & II), and Bravo series. Always confirm by cross-referencing your original part number with the equivalents listed (10-97934A1, 18-2141, 21810).

What are the signs that my engine mount bolts need replacing?

Symptoms of failing mount bolts include excessive engine vibration, clunking sounds during startup or when shifting gears, or visible corrosion and degradation of the existing hardware.

What is the difference between OEM and aftermarket parts?

This listing is an aftermarket replacement (not OEM). It has been engineered to meet or exceed OEM-level specifications using comparable materials. Our parts are manufactured in an ISO 9002 certified facility and are batch-inspected to ensure quality and consistency.

What are your shipping speeds and costs?

We ship worldwide quickly, with a typical transit time of 5–15 days for most regions. Standard shipping is free. Expedited shipping options, if available for your location, will be presented at checkout.

What is the warranty and return policy?

This product is covered by a 1-year warranty against manufacturing defects under normal use. If you encounter any issues, please contact our support team with your order details. Returns are accepted within our standard window for items that are unused and in their original condition. See our full policy page or reach out for instructions.

Safety & Important Info

Verify images and specifications against your original part before purchasing. If anything differs—even if your model appears on a compatibility list—do not purchase.
This is an aftermarket replacement part, not an original equipment manufacturer (OEM) component.
Professional installation is highly recommended for safety, performance, and to prevent damage to your vessel.

About Sea Sierra

Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and rigorously tested for real-world conditions.
Fast Global Fulfillment — We offer free standard delivery to most regions, with parts typically arriving in 5–15 days.
Manufacturer-Direct Value — By working directly with manufacturers, we provide fair pricing without compromising on materials or quality control.

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