My Model A couple has a small block Chevy in it. I'm going to install a early Hemi in it. The Chevy mounts are of course welded to the inside surface of the custom built boxed frame. I will need to fabricate new mounts for the Hemi. The frame is painted car color on the outside and top surfaces of the frame, and simple black on the inside and bottom surfaces. Is there any way to weld on the inside of the frame and not burn the paint on the outside and top? I don't care about the black paint, but I am concerned about the yellow on the top and outside of the frame. I'm not a welder, I'll have to hire someone to do the welding, so I'm not familiar. I thought about packing the frame area adjacent to the welded area with wet cold rags, and perhaps welding just a small part of the weld at a time to both not heat soak the area too badly and disperse the heat with heavy wet rags. I have no idea at all if that's feasable. Instead of welding is it feasable to bolt in new mounts? Is it ever done where the new mounts are adapted to the existing Chevy mounts? I've not done anything like this before, so if anyone has any input on alternatives to having to get the frame painted again I'd like to hear about it. The frame is painted like the car, it's a custom color with very fine gold metal flake and pearl, and it's tough to match - it would be a big hassle to try to match the frame and likely expensive too. I'd really like to avoid all of that.
A decent weld with good penetration, which is what you want for a motor mount will absolutely burn the paint. Figure on repainting
Lets see a good picture of the current mounts. does it have the classic Ford rubber biscuit mounts? if so maybe you could use the old Hurst mounts on the Hemi?
Agreed, and while in theory you could design some bolt on mounts, in order to be strong enough, they'd need to bolt THROUGH the frame, leaving unsightly bolt heads on the outside of the frame. I'd guess that building custom adapters from the current mounts to the new engine would be the best route. Should be relatively straight forward once you have the Hemi mocked up in it's new position.
>>>Instead of welding is it feasible to bolt in new mounts?<<< Sure. Drill holes Use thread-coil wire from a hitch-mounting kit to pull bolts through the inside of the frame into the holes.
As a welder that has built a lot of custom motor mounts, I would like to see the current mounts, and see what the purposed new mounts would look like. Depending on how the original mounts were attached to the outer part of the frame and how the frame boxing was done, you could possibly build from the existing mounts without damage to the top and outer painted frame. Won't be easy, and quite possibly not doable, but without seeing what is there to work with, we are just guessing.
Thanks guys - I won't be able to get to the car for a day or two. I'll send some photos of the current mounts once I can get to it.
Bolt on wouldn't be that complicated with some CE engine mounts and cushions along with the appropriate width weld-on frame mounts. Position the engine with the mounts and cushions, trim the frame mount's width 1/4" shy of the rails, cut a rectangular piece of 1/4" steel to fit between the mount and frame. About the height of the rails and a couple inches longer than the frame mount. Tack the frame mounts to the plate, remove and weld up. Lay out at least five 3/8" holes in the new mount; two on each end and one under the U of the frame mount. Fit back on the engine mounts and mark the holes in the frame. Pull the engine, drill the 3/8" holes in the frame along with access hole, maybe an inch or so in the center. Take some 3/8"x 1-1/2" bolts and weld some "anti-rotation" bars to the heads to facilitate tightening from the outside, along with a foot or so of mig wire to the end of the bolt. Add some heavy washers, fish the bolts thru the holes, and bolt the mount down (leaving the mig wire in place). Drop the engine back in and see if it all fits back together. If all good pull the engine, remove the frame mounts, paint stuff as needed, put it all back together, and trim the mig wire off. Biggest headache would be that you stated you were not a welder and fabricator. You could borrow a 110 mig, do a little practicing until you could comfortably tack the mounts. Then take them and the bolts to a welder. Did something similar at work many years ago. Had to fit some brackets on the tube framework on some equipment we were modifying; worked out well.
I take it by Hemi, you mean Chrysler, as the early Dodges mounted off the timing cover. Here is a set of mounts with urethane insulators. Custom mounts like these could be fabricated with the ears welded to a plate and bolted to the boxing plates on your frame. I would form a 1/2" flange at the top of the plate to rest on the top of the rail, drill and weld 4 threaded bungs to the inside of your rails. Done properly with a Tig welder it could be done without burning the paint on your rails.
I'd be exploring Martys version but possibly substituting welded bungs for steel nutserts = no welding on frame. The way it looks to me is that the engine weight is transferred to the frame on the angle bracket that would lie on the top of the rail. Thus the fixings to the frame are holding the bracket in place, not supporting the load. And besides, nutserts are rated pretty highly, talking 3/8 or bigger. Chris
Carriage bolts come in Grade 8 and 5. Put them in a drill, work them on a belt sander, etc and sand the marks off. Would look like rivets then.
Tin Man Fab makes some urethane bushing engine mounts for the early hemi; similar to the ones in @Marty Strode post.
>>>Just found what you mean on YouTube. There are no access holes in the frame to do that. >>>> Then make an access hole in an inconspicuous spot. Make your own mounting kit with cotter-pin bolts, blocking plates & bailing wire to pull into place.
My '32 frame had mounts for a Hemi and I am running a small block now. I made new mounts on the engine side that adapted to the Hemi mounts on the frame. Maybe you could do something similar?
dont bolt engine mounts ,, i had a small block ford engine a 289 fall throug at 40 mph omg you dont want that ! and that hemi weighs a few hundred more pounds than a 289
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