Float a motor vs. stock mounts

BILL WILLIAMSON said:
Oh My!
What have I started, again! The rear end is still pushing against a similar "member" resulting in only a very slight rubber flexing of the rubber biscuit, not unlike the slight rubber flexing in the rubber pads between the stock mounts & the frame rails.
FAM's is NOT like mounting the motor with GIANT rubber bands! Bill W.
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If its not unlike the slight flexing of the stock rubber pads then why change and give up the frame rigidity?
Think about it, with the stock mounts the frame rails can't twist at the rear mount area.
As the engine torques on the Floatamotors do to their design they try to twist the frame rails and their is less rigidity to stop it.
Model A frame rails are not real rigid and need all the help they can get.
Bill
 
I think you need to start with a genuinely TIGHT car to feel the changes that come with floaters. Most notably the added flexing of the frame side members adds instability to the steering like a wobbly sector shaft. Other issues are more "wear and tear" issues that will have little impact since most folks drive their cars under 1k miles a year.
 
in 1963, I installed FAM, in my 31 Tudor. I drove it through college. There was no noticeable change. That car went into storage, I restored a 31 Vicky wo/FAM and did not seem to notice a difference. I later pulled the 31 Tudor out of storage, and discovered that it was a 55B Dlx, re restored it correctly taking off the FAMs and noticed that the engine did not twist as much when accelerating. The correct motor mounts also gave a structural integrity that was noticeable. Back to the Vicky and Marco's comment. The frame on that car was slightly twisted. I did not understand that, so I sold the Vicky with the twisted frame often wondering what happened to it. The second time for the Tudor, I put the frame on a steel bed, and gauged everything. Then straightened out all the bends and twists. If found out later from the son of the original owner that the car had almost rolled into a ditch one night pulling cotton trailers in Texas, which also explained the severely worn 2nd gear. When the body was fitted back to the straightened frame, and I followed Marco's article on straightening the frame, the entire car fit together perfectly like it never had...radiator shell to hood, hood to body and doors to body. Invest time in that frame and it will pay you great dividends. Now, all this fits under my rule number one of Model A Restoration...ALWAYS USE OEM PARTS...and rule 2 is like it...ALWAYS USE OEM PARTS...and rule three, a bit different but similar...NEVER USE REPOPS...and finally, I will tell you who satan is...he is the one who makes repops and reproduction wood parts that...don't fit...Swoff
 
You can throw away your frame spreader. FAM's make engine in/out easy. Most users leave off the rear ****** center support piece. Bad idea. That element transfers some weight off the mounts to the center cross, permitting the engine to truly float, not just sit heavily on the donuts. It also maintains the original 3 degree engine alignment. Without the center support piece the frame does tend to flex. With, the frame has less load at the rear engine mount points than with the stock setup. The rubber durometer is way to high on most current FAM donuts. Originals were softer non-synthetic rubber. Someone was making softer cast red urethane donuts for them some time ago. Also, the originals were cast iron, not cast aluminum.
 
BRENT in 10-uh-C said:
Without getting into a "whizzing contest", the biggest thing that folks don't consider is the rear engine mounts are actually what the rear end pushes off of to move the weight of the entire vehicle. That is why it is a needed structural member.
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Brent,

I too have no interest in a contest, but are you sure about "the weight of the entire vehicle"? Surely, the weight of the drive train and motor are pushed on directly, right? Also, it seems like the rear springs, which connect the drive train to the body, must transmit at least some force to the body.

Steve
 
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I've used both float-a-motor mounts and originals. My preference is to stay original for any number of reasons including the structural integrity of a more solid mount. That said, I haven't noticed any difference in vibration or other noticable differences as to the overall comfort and driveability of the car(s). I still have float-a-motors in my roadster, but only because the frame is slightly more narrow at that point due to some earlier frame damage, and I was not able to get the original mounts to work when I rebuilt the engine several years back. Personally I can't tell the difference between the roadster and the other cars that have the original mounts. For these reasons I prefer to stay with the original equipment. Hope this helps.
 
Yep, you're always starting something, Bill! Oh, and I'll be in your back yard tomorrow.

Anyway, I had the spring mounts in my car when I bought it, and it always ran pretty smooth with a stock motor. However, my crank never lined up right, and it was always different. The crank working is vital for timing the distributor and other things, so it was frustrating.

Ended up redoing the motor mounts with stock. At first, I thought the motor was running poorly. I never felt so much vibration in that car! However, the crank lines up perfectly every time now, so give and take.

I got used to the vibration now, but at first, it was a little frightening.
 
P.S. said:
Yep, you're always starting something, Bill! Oh, and I'll be in your back yard tomorrow.

Anyway, I had the spring mounts in my car when I bought it, and it always ran pretty smooth with a stock motor. However, my crank never lined up right, and it was always different. The crank working is vital for timing the distributor and other things, so it was frustrating.

Ended up redoing the motor mounts with stock. At first, I thought the motor was running poorly. I never felt so much vibration in that car! However, the crank lines up perfectly every time now, so give and take.

I got used to the vibration now, but at first, it was a little frightening.
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PS,
Spring mounts??? I'm referring to the FAM rears and the FAM front set up with the steel bar & 4 rubber biscuits that replace the whole yoke type front mounting. Very much like the '32 Model B mounting. To align the crank bearing, I only had to add 2 large flat washers above the upper "biscuits."

Everyone,
Do your car like you want to! I just know it made a miraculous change in my '30 coupe! Over 45 before, sounded like I was tearin' up my engine, after new mounting, at 65, it was just like HMMMMM! and my butt didn't get numb anymore!:D
I honestly believe that the stock mounting DOES NOT prevent frame flexing, many frames flex. I wonder if the Model A frame was designed to flex so it could deal with poor roads & rough terrain?
Even on a "TIGHT" Model A, quoting Marco, not only will the frame flex, but the body will also. How about when you exit a steep driveway on an angle and one of your doors suddenly flies open!:eek: Same driveway, how about those "sweet" creeking sounds from a woodie wagon!:D Or when some fordors are parked on devilish uneven terrain, and maybe one door is stuck shut!:eek:
Just food for thought:confused: If I've lost friends with all this ramblin,' that's O.K, I THINK I still have 3 friends locally:confused:??? Plus the Dog! Bill W.
 
Yep, Thats all a lot to consider... I think that enough reason was given to accept that changing the org. pads will do in my rebuild.

Besides with this new found crack in the front cross member, the last thing I want to consider is drilling holes in anything!
 
lance leblanc said:
Yep, Thats all a lot to consider... I think that enough reason was given to accept that changing the org. pads will do in my rebuild.

Besides with this new found crack in the front cross member, the last thing I want to consider is drilling holes in anything!
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Lance,
Is drilling holes a CARDINAL SIN?:eek: Maybe I should throw away my drill motor, drill press, drill bits, & UNI-BITS & GO TO Confessions?:eek: Unwanted holes can be welded up, just ask FLOP! He's a GENIUS AT IT. Betcha' he could build a roadster out of a Sow's Ear!:p Look what Purdy Swoft built out of an old roadster that looked worse than a Bonnie & Clyde Car that had been chased through a narrow woods road!!:D Bill W.
 
steve s said:
Brent,

I too have no interest in a contest, but are you sure about "the weight of the entire vehicle"? Surely, the weight of the drive train and motor are pushed on directly, right? Also, it seems like the rear springs, which connect the drive train to the body, must transmit at least some force to the body.

Steve
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Well, I guess it comes down to where whether the rear spring hangers (shackles) are correctly installed/tightened but if installed correctly the spring will rock fore & aft some.
 
BILL WILLIAMSON said:
PS,
Just food for thought:confused: If I've lost friends with all this ramblin,' that's O.K, I THINK I still have 3 friends locally:confused:??? Plus the Dog! Bill W.
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You sound like a sane guy, if you run short you can call me a friend so now you're up to 4 again (maybe not locally)...

Was there ever an engineering study done by those who promote the frame flexing with FAM due to rotational forces? The way mine is bolted together I just don't see this being an issue. The only concern I would come up with is metal fatigue due to repetitive stresses, but the improved high frequency isolation should reduce this compared to the original pads.

As stated in my earlier post, changing the mounts made a big difference in drivability since the original rubber had deteriorated. In ordering the FAM, I looked at it as only having to mess with the original wedged in mounts once (PITA). Since they were acknowledged in the mechanics handbook, I considered it to be low risk as well.


Craig
 
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A sagging frame must have been an issue with the stock mounts early on too.I have this strap affair that mounts to the frame on the outside,replacing the outside mount plates.The strap part passes under the flywheel housing,with a notch to clear the hanging cotter pin.Then the two long threaded rods bolt to that,with the adjustable plates passing through the side plates.When they are tightened you can see the engine rise up and the frame twist back into place.With this in place now you have true metal to metal contact between the engine and frame.The paperwork in the box is dated 1933.I don't know what I will ever do with them,but I have two sets.One set came from a garage that closed here on Pearl Harbor day,1941,and the other set I found on ebay.I bought that set because it was cheap and I had the only other set I'd ever seen.I have still never seen another set.
 

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lance leblanc said:
Yep, Thats all a lot to consider... I think that enough reason was given to accept that changing the org. pads will do in my rebuild.

Besides with this new found crack in the front cross member, the last thing I want to consider is drilling holes in anything!
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The correct way to weld repair a crack is to first drill a hole in each end of the crack before it is welded. With the size and length of the crack in your cross member i would probably go with a 3/8 hole at each end. It's just the way i'm used to doing it.
 
gibby said:
The correct way to weld repair a crack is to first drill a hole in each end of the crack before it is welded. With the size and length of the crack in your cross member i would probably go with a 3/8 hole at each end. It's just the way i'm used to doing it.
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gibby,
I just said to the Dog, "Gibby's a man after my own heart, he's not afraid to drill holes in A Model A! and for a good reason! Yes, I understand about NOT drilling holes in high points cars. How many unused holes did Henry drill or punch out in a Model A? I have no idea. I'll drill 2 holes in Vermin to mount my starter solenoid, 'cause with my leg braces, I can't pivot my foot to get on that dang starter button, but I won't drill the dash rail for a push button 'cause I'm puttin' in a KEY start switch. I'll also drill a hole to mount a good flexible tail pipe hanger. God! you all would "CRINGE" if you saw all the lightening holes I drilled in '50's era dragsters. I remember a drag coupe named The Cheesecake Special that had HUGE holes sawed in the outside walls of his Flathead V-8 waterjackets, I guess it was AIR COOLED! Almost everything was drilled or hole sawed, except the body and the car was featured in Hot Rod Magazine! And that's my "HOLE STORY!" Bill W.
 
BILL WILLIAMSON said:
gibby,
I just said to the Dog, "Gibby's a man after my own heart, he's not afraid to drill holes in A Model A! and for a good reason! Yes, I understand about NOT drilling holes in high points cars. How many unused holes did Henry drill or punch out in a Model A? I have no idea. I'll drill 2 holes in Vermin to mount my starter solenoid, 'cause with my leg braces, I can't pivot my foot to get on that dang starter button, but I won't drill the dash rail for a push button 'cause I'm puttin' in a KEY start switch. I'll also drill a hole to mount a good flexible tail pipe hanger. God! you all would "CRINGE" if you saw all the lightening holes I drilled in '50's era dragsters. I remember a drag coupe named The Cheesecake Special that had HUGE holes sawed in the outside walls of his Flathead V-8 waterjackets, I guess it was AIR COOLED! Almost everything was drilled or hole sawed, except the body and the car was feature
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d in Hot Rod Magazine! And that's my "HOLE STORY!" Bill W.
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Bill, my friend, I won't get into the FAM frey... If you like them thats good for me!! Here is the roadster, it had a right smart of holes, drilled with a 30 30 or some such. Deb wanted to leave the body as it was. I couldn't resist trying to make a purty out of it. I hammered em out, gas welded em and hammered em sum more. Purdy D Swoft.
 
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CarlG said:
Bill, have you found a key start switch that will fit the dash without hitting the gas tank?
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Carl,
I got it from Macs, and I'm quite sure it's short enough. One guy dinged in his gas tank:eek: to make a longer switch fit. I always glue a leather patch behind it, just in case-----Bill W.
 
Purdy,
I found some FAKE bullet hole stickers, put one on the roof, right behind my HEAD, folks would say, NOW! we know what's wrong with you! Ted, in his kindness, said, "If you'll pull out the upholstery panels, I'll weld it up for you, but I cain't fix your HEAD!" Bill W.
 
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