Bushings Inc. DF-2207-1 Dual-Flex Marine Engine Mount | 1/2"-20 Stud | 450–750 lb

Bushings Inc. DF-2207-1 Dual-Flex Marine Engine Mount

Part Number: DF-2207-1  |  Brand: Bushings Inc.  |  Series: Dual-Flex DF-2200

The Bushings Inc. DF-2207-1 is a heavy-duty adjustable marine engine mount from the Dual-Flex DF-2200 series, rated for engine and powertrain installations weighing approximately 450–750 lb (204–340 kg) when supported on a standard four-point mounting arrangement.

The Dual-Flex design isolates vibration in the longitudinal, lateral, and vertical directions using a progressive elastomer that cushions at low load and stiffens under higher engine loads. The heavy-duty aluminum alloy base, oil- and fuel-resistant elastomer, and corrosion-resistant plated hardware make it well suited to the marine environment.

The threaded 1/2"-20 stud provides approximately 0.8 in. (20.3 mm) of vertical adjustment for engine alignment. The design is fail-safe, with no metal-to-metal contact between the engine-side and bed-side mounting members under normal operating conditions.

The corresponding heavy-stud version is DF-2207-2, which is identical in footprint but uses a 5/8 in. stud. Confirm your required stud size before ordering — the two are not interchangeable.

Specifications

• Part Number: DF-2207-1
• Brand: Bushings Inc.
• Series: Dual-Flex DF-2200
• Product Type: Adjustable Marine Engine / Transmission Mount
• Stud Size: 1/2"-20 UNF
• Mounting Bolt Size: 3/8 in. (9.5 mm)
• Mounting Hole Centres: 4 in. (101.6 mm)
• Overall Length: 5 in. (127 mm)
• Overall Width: 2.75 in. (69.9 mm)
• Overall Height: approx. 3.81 in. (96.8 mm)
• Minimum Clearance Required: 2-3/8 in. (60.3 mm)
• Vertical Adjustment: approx. 0.8 in. (20.3 mm), less engine-foot thickness
• Rated Capacity: 450–750 lb (204–340 kg) per set of four mounts
• Base Material: Heavy-duty aluminum alloy casting
• Elastomer: Oil- and fuel-resistant compound
• Hardware: Zinc-plated steel
• Weight: approx. 2.0 kg / 4.4 lb (each)

Compatible Applications

The DF-2207-1 is suited to any marine engine and transmission installation meeting the weight, stud size, and mounting-hole dimensions above. Engine brand alone does not determine compatibility — verify the full installation weight and mounting dimensions first. Documented installations have included:

• Chris-Craft marine engines
• Ford marine engines
• Isuzu marine diesel engines
• Perkins marine diesel engines
• Renault marine engines
• Universal marine diesel engines
• Volvo Penta diesel engines
• Westerbeke diesel engines
• Yanmar diesel engines

Actual fit depends on the engine-bed layout, combined engine and transmission weight, mounting dimensions, and required alignment range, not on engine brand or displacement alone.

Fitment Notice

Before ordering, confirm all of the following for your installation:

• Combined engine and transmission weight is within 450–750 lb (204–340 kg) on four mounts
• Stud size required is 1/2"-20 UNF (if 5/8 in. stud is required, see DF-2207-2)
• Mounting hole centres are 4 in. (101.6 mm)
• Mounting hardware is 3/8 in. (9.5 mm)
• Minimum clearance of 2-3/8 in. (60.3 mm) is available
• Required vertical adjustment is within the mount’s range

When to Replace Engine Mounts

Inspect mounts at each annual service. Replace when any of the following are found:

• Elastomer is cracked, split, hardened, or separating from the metal
• Mount has sagged, collapsed, or shifted out of position
• Engine vibration has increased noticeably at all speeds
• Shaft or coupling alignment will not hold after repeated adjustments
• Excessive engine movement is visible under load
• Stud or hardware is bent, stripped, or badly corroded
• Engine or transmission service reveals deteriorated mounts

Worn engine mounts allow drivetrain alignment to drift over time and transmit significantly more vibration into the hull structure.

Installation Notes

• Mount onto a structurally sound engine bed using properly sized 3/8 in. mounting hardware
• Use the 1/2"-20 stud and leveling nut to set engine height and establish correct shaft or coupling alignment
• Lock the adjustment nut without disturbing the engine position once alignment is confirmed
• Install all four mounts before finalizing alignment — do not adjust mounts individually after the engine is loaded
• Recheck alignment after launch and again after the first several hours of operation, as mounts typically settle slightly under load
• Confirm that engine movement under full-throttle load is within acceptable limits after installation

Cross-Reference Part Numbers

• Bushings Inc.: DF-2207-1
• Also listed as: DF2207-1 / DF22071
• Catalog reference: BUIDF22071
• Related: DF-2207-2 (identical footprint, 5/8 in. stud)

Related Products

• Bushings Inc. DF-100 Dual-Flex Marine Engine Mount | 850 lb Capacity — heavier-duty Dual-Flex mount for larger engine installations

Parts Desk Insights

Best use case: The DF-2207-1 is a solid choice for mid-size diesel sail and power installations in the 450–750 lb combined engine-and-transmission range — Yanmar, Westerbeke, Universal, Perkins, and similar units fit squarely in this bracket. The Dual-Flex progressive design handles both the low-speed idle vibration common to diesels and the higher loads at cruise without needing a different mount for each condition.

Common issues: The most frequent ordering mistake is confusing the DF-2207-1 with the DF-2207-2. The two mounts share the same footprint and weight rating but use different stud sizes — 1/2 in. versus 5/8 in. — and are not interchangeable. Check the existing stud with a thread gauge or measure the wrench flats before ordering. The second common issue is selecting by engine model name rather than confirmed installation weight: an engine may fall in the DF-2207 range without its transmission, but exceed it once the full powertrain is accounted for. Always weigh or look up the combined engine-and-transmission weight before specifying the mount.