MTFCA Forum

Has anyone ever tried to reduce engine vibrations transmitting to the chassis by placing a strip of rubber between the engine arms and the frame?

One can quite effectively limit vibrations by a full engine/transmission balance job. Dont run your motor above idle speed.
Transmission drums, especially early 20's on, are way out. Yes, its a lot of work & scattered motor parts, but worth every minute spent.
There's no quick fix I know of.

I balanced the engine and transmission when I rebuild it, I was just wondering whether you could make it even smoother

I'm a balanced T engine proponent.
The comparison between my '23 and my balanced rebuilt '26 is night and day. '26 runs like an electric motor. Was worth every penny to go the extra step.

They would have to be relatively thick strips of rubber to help any. Look at the pucks used in the aftermarket float-a-motor mounts for the Model A.

It may sound insignificant, but take your fan off and check it for balance. Some can be way off and cause a surprising amount of vibration. Big difference after balancing mine.

I’ve achieved excellent results by cutting 2”X3” pieces out of an old truck mud flap, drilling holes for the bolts and slipping them under the pan ‘arms’. I’ve even cut a larger square out of the mud flaps and slipped it under the pan sump and above the accy ‘belly bra’. Of course I cut a larger oil drain hole there.

I don't think you can reduce vibration significantly by putting rubber under the pan arms. You'd still be metal to metal at the front mount, and if you create compliant mounts at the rear of the engine, the rear axle will be moving the engine around as the front and rear wheels go over road irregularities. Balancing the engine to reduce vibration can be effective. A balanced engine with a counterbalanced crankshaft will run much smoother.

Pat, have you driven a particular Model T without- then with pieces of truck mud flaps under the crankcase arms ??Try it then you won’t have to conjecture “I don’t think”...
It works..the rear axle doesn’t “move the engine around” in the least.

Seemingly trying to make a Model T run as smooth as a modern car would just ruin all the fun and "atmosphere". I have 3 Ts, and in the past up to 5, and they all ran differently from spunkiness to smoothness. Its what makes it uniquely fun.

Keep in mind that the Model T engine mounts play a significant role in locating the front and rear axles. Another thing to consider is that the engine will vibrate more freely if it is not bolted tightly to the frame, and if you add flexibility to the rear engine mounts, the engine mount bolts will be able to move as the engine vibrates and as the frame flexes and create wear at the point where the bolts pass through the frame while wearing notches in the bolts. You will also raise the rear of the engine by putting shims under the mounts, and that will raise the drivehaft and pedals along with the engine. I suspect you might do more good to balance the engine assembley and stay with Ford's mounting arrangement. It might be interesting to try bolting a couple of modern, bonded rubber sandwich type 4 cylinder engine mounts to the frame and bolting 4-5 lb weights to the engine mounts. That might act to dampen vibration in the frame. Bolting such a device to a bracket attached to a couple of head bolts might help dampen the engine's normal vibration, also. Engine/transmission mounts are available in almost infinite variations.

Ford did some rudimentary design work to lessen engine vibration transmitted to the chassis in the Model A car. They went much further with the Model B 4 cylinder cars. Besides drastically reducing the engine's inherent vibration, they improved the transmission and engine mountings and added a device that attached to the engine and firewall (?) to dampen vibration. The Model T design does not lend itself to retrofitting these improvements. Ford also used heavy stay rods from the engine to the frame on the later cars to limit engine movement caused by road and drive/braking forces reaching the engine from the rear axle via the torque tube. Eventually, even Ford adopted the Hotchiss type driveline, which allowed much softer and more compliant engine and transmission mountings without compromising running gear stability. Improvements in engine design, notably the counterbalanced crankshaft, also made engine vibration much less of a problem.

...and now you’ve heard, yet again, from Mr. Wizard...

Look at how Ford mounted the Model A engines, both the early production cars and the later ones. They added rubber sandwich insulators at the rear mounts, and changed the original rigid front motor mount to a spring arrangment that allowed some up and down movement of the engine. Besides that, the Model A engine had less inherent vibration than the T by reason of its heavier and stiffer crankshaft, aluminum pistons in most production, and a massive flywheel and clutch assembly, offset crankshaft, and more accurate factory balance. The simple sliding gear transmission contributed very little to vibration. The Model A weighed more than the T, and had a much stiffer frame and double acting hydraulic shocks all around as well as a stiffer body structure. They still vibrated, though less than the T. Ford finally got vibration under control with the V 8 engine. The B model fours had a number of improvements specifically aimed at reducing engine vibration. These improvements went far beyond a piece of rubber under the rear engine mounts.

Trying to optimize the placement and the durometer (hardness) of the rubber would probably drive a person to insanity. Just balance the engine, transmission, and fan blade (which I hadn't thought about) and then drive and enjoy.

Art Mirtes

If you had a pan with broken ears, you could do some experimenting. Modify the pan ears and fabricate some hanger brackets to bolt to the original mounting holes in the frame, then try putting something like the 1940s flathead V8 front motor mounts on each side. Or look at some of the thousands of different engine and transmission mounts that are available and see if you can find something that will fit in the limited space available and allow some limited movement and vibration dampening. To really fix the vibration, you'd need to design a crossmember for the frame to locate the front radius rod socket and to allow for properly-designed rear mounts along the lines of what Ford did in the 1930s and beyond. The way the T is built, the engine vibration has a number of pathways to the rest of the car, and the light weight and flexibility of the car assures that all sorts of vibratory motions will occur at various speeds. Reducing engine vibration at the source is the way to go. Or get a nice Model B roadster. They're available for about $76 K....

I think, correct me if I’m wrong, there was a thread or a mention about Ford placing springs between the ears of the pan and the frame. I think it was on the TT, perhaps I also read or was told that they removed the block of wood in that arrangement. Not sure if fact or fantasy but thought I’d at least mention it for clarification. Best John

There is such a thread. I don't know if the TT springs were under the ears on top of the frame or under the bolt head or nut, or if they were put in place of the blocks. I ran my car a year without any blocks, then got some new blocks and installed them. The car seems to track a little better with them. I didn't notice much change in vibration, maybe a little less. I had to get the sideways bolts a little tighter than I wanted to get the cotter pins in. After a day or two, they had loosened. They probably need tightened a round or two now that the blocks have worn in. If I had a TT, I would try to set it up the way Ford did it originally. I've seen a clean, straight TT frame with a decent cab on it that had broken in two at the right hand motor mount holes.

Interesting!

I am with George, I have run rubber pads on my T's and it does nothing but help. I have put over 100,000 miles on one of them and there is no wear on the frame or the mounts and I run mine pretty hard. Some people seem to go on theory alone and don't do any research. A theory is just that until proven or disproven.

How Ford did it: www.oldcarbrochures.com // Brochures list // Ford // 1932 Ford Four Foldout // See: Engine mount details

Careful Dennis You’re liable to attract the ire and conjecture of Mr. Wizard.....oh, he’s gone over to the Early V8 Forum...

I put rubber washers cut from old inner tubes under my body mounts and now my car rides like a brand new 1956 Cadillac. Faster accelleration, higher tops speeds, super gas mileage .... no vibration, rattles or squeaks, and when I park, the bugs jump off my windshield and wash and wax the entire car. Ford engineers were dumb as rocks!

In the grand scope of things, I don’t care what anyone says, that’s funny.

Ricardo Montalban, star of "Fantasy Island", recommends using only fine Corinthian lather for pan arm washers.