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Taylormade

Floating Power

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I'm getting ready to cast the motor mounts for my 1932 Dodge DL. I'm going to use Devcon Flexane, which is a liquid urethane rubber that can be poured into a mold. I've used this stuff before to cast axle bumpers for my 29 Plymouth and it worked great. But axle bumpers are one thing and motor mounts another. Lots of things could go wrong here if I'm not careful. The problem I'm dealing with is two-fold: one, what hardness should I use for the rubber? As far as I can tell, Flexane comes in 60, 80 and 94 hardness. 60 is flexible, 80 is quite hard and 94 is like a hockey puck. I'm not sure how hard the rubber used in the Dodge mounts was. Certainly 94 is out of the question, but 80 seems like it might be too much, also. I read several articles on making mounts for more modern cars and most felt the 80 was firmer than the original stock mounts. The problem - I can find 80 all over the place, but 60 seems to be available only in the U.K., and I think 60 is what I need.

Problem two - my mounts are a mess. They've basically disintegrated into a semi-melted lump that is a formless blob squished flat. Are there any illustrated parts books that show a picture of these mounts? If so, I could come close to duplicating them. At the moment, I have no clue as to how thick they were originally.

Devcon makes a primer that really bonds the rubber to the metal. I experimented on my axle bumpers and the metal started to bend and tear before the rubber pulled off, so I'm confident this is as close to vulcanizing I'm going to get. Anybody want to chime in?

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Benefits of AACA Membership.

I applaud your goal of doing as much yourself as possible on that. And one day I need to make some axle bumpers so I might follow your lead on using Flexane for that.

But for engine mounts I'd send them off to someone like the folks at Antique Auto Parts Cellar (a.k.a. Then and Now Automotive) and have them revulcanized.

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I contacted them and they have the molds for my DL - which was a surprise. Just waiting for a call back for the price. I plan to be sitting down with heart medicine at hand.

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I applaud your goal of doing as much yourself as possible on that. And one day I need to make some axle bumpers so I might follow your lead on using Flexane for that.

But for engine mounts I'd send them off to someone like the folks at Antique Auto Parts Cellar (a.k.a. Then and Now Automotive) and have them revulcanized.

For motor mounts this is also where I would be thinking

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The rubber pieces are basically rectangles about 3/4" thick. They just come out to the edges of the metal sandwich. Rubber belting works quite well so that should give you an idea of the relative hardness of the mounts. There is no downside to this. I have video of the production line at Chrysler and the guys seem to have been told to test every engine after it was installed in the frame and you can see one guy grab the motor near the water inlet and shake the motor side to side by about 4" or 5" inches! And that was with one hand. Rubber belting will not allow that much travel but it seems to have not caused any problems over the years. So as I say there is most likely nothing you can do wrong short of "freezing" the motor in it's mounts or have rubber so soft the mount squishes down. Any hardness between the two extremes would be OK.

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(Site won't let me edit my previous post.) The thickness of rubber must be the same on both mounts. You can tell if everything worked out OK if the fan blades are parallel with the back of the rad. If you were to have the engine cocked to the rear or the front,the gear shift lever,which is not connected to the transmission but "floats" above it , would "find" the gears in a different place and possibly bind. It's also possible in an extreme case for the lever not to be able to find one of the gears. There is also a possibilty of binding the clutch mechanisim and the exhaust pipe. But this is in an exteme case. Whatever hardness of material you put in there must support the engine without any squishing. It must also take heat especially the rear one.

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