Two Bolt Vibration Mounts for Hovercraft

I recently had a customer call me and inquire about a solution to isolating some vibration he was encountering in a custom project. He was building from scratch a one seater hovercraft. By custom fabricating a body and frame from an old Go-Cart he also managing to refit an aircraft engine to turn the propeller in the back, to make a truly unique hovercraft.

He had the mounting frame already left over from the aircraft and had to find a way to not only mount that engine to the the frame of the hovercraft, but also to diminish any vibration that the engine would put out.

When he called he didn't have a part number or model or make number, all he had was the left over anti-vibration mount that was attached to the engine when it was mounted to the aircraft. So instead he took a picture of the mount and sent it to me.

The mount is a Two Bolt Instrumounting made by Metalastik. Once we knew what the mount itself was, we needed to find out which two bolt mount is was and how stiff the rubber is. I had him give me the measurements of the vibration isolator, including the height, length, width, bolt circumference and bolt length. After converting the measurement from metric I matched them up with the dimensions chart in the Trelleborg Product Catalog.

I found that the specific vibration isolators he was looking for was the 17/1385-60. The next question was how many mounts does the engine itself require to be mounted. The engine frame had six different locations that would mount up to the frame and since the engine would me mounted on its side rather than the bottom the Max Load in Shear for the vibration isolators divided by how much the engine weighed was more than enough to isolate the vibration that the engine would be putting out.