Engine mount "bedding"

Designs for inboard or outboard power

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Brian
Posts: 179
Joined: Mon Feb 18, 2013 10:06 pm
Location: Hawaii

Engine mount "bedding"

Postby Brian » Thu Sep 13, 2018 6:38 pm

I think I've got the right terminology here, for the wood pieces that are bolted to the inside of the motor stringers, upon which the actual steel engine mounts will sit and be secured to. They are to be bolted through the stringers. "Bedding"? Whatever.

In any case, I think the standard is White Oak, but I have also read that Black Locust may be superior, yet a little harder to work. But all I'm going to do is saw it to length and drill holes in each of 4 pieces, each 2" X 4" and length about 16-18" to allow for bolt spacing (front, rear, port, starboard). Anyone have any thoughts on "bedding", or whatever they're called, as well as installation? Wood sources?

These pieces will be mounted level with the stringers, so the engine will be level for hatch clearance. The engine has a 12 degree trans on it, and the shaft is about 11 degrees. I plan to make up the degree as I marry the flanges, by adjusting the front and rear mounts. Sound right?

TomB
Posts: 316
Joined: Wed Jan 18, 2017 4:07 pm
Location: Holland, MI

Re: Engine mount "bedding"

Postby TomB » Thu Sep 13, 2018 7:14 pm

Brian,

Bedding sounds right. I plan to use two pieces one port and on starboard. The engine mounts are 22-24" center to center and I think a single piece would be stronger.

I have been chasing my tail looking at transmissions, I thought I had a 12* tranny identified that turned out to be 8* with a 4* down angle. What kind of transmission are you using? The transmission mounts are often at different elevation than the engine mounts with plus/minus a 1/2" of travel in the mounts themselves so you may need to do some sculpting on the bedding.

Tom

Brian
Posts: 179
Joined: Mon Feb 18, 2013 10:06 pm
Location: Hawaii

Re: Engine mount "bedding"

Postby Brian » Fri Sep 14, 2018 12:56 am

I have a support in the way, so it will be two halves on each side.

The trans came on the Ilmor 430. It is a ZF. The mounts are almost level on the stand, with about 2" of travel, so plenty of adjustment.


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