Front motor mount springs

mrtexas

Well-known member
I took the bottom springs off my front motor mount, the only pitiful repops that are available from the usual suppliers(on the car when I bought it). I believe they are one reason 3 rear motor mount ears were broken and the 4th one cracked

The springs on the top are original? If not can someone post a picture of originals?
MMSprings.jpg


In the end I decided to use this beefy after market motor mount. I installed a 39 transmission and they don't come with an attachment to the crossmember:

MMBracket.jpg
 
I think you're going to have a problem there. Looks like there is NO cushion there at all.Even Henry added solid cushions to the V8's (front and rear) in one form or another. JMO
Paul in CT
 
I think you're going to have a problem there. Looks like there is NO cushion there at all.Even Henry added solid cushions to the V8's (front and rear) in one form or another. JMO
Paul in CT

There are large rubber cushions under the bolt head on each side.
 
I would use the original style like the bottom set in your first picture. That is the best style to allow for frame twist.
 
I wonder if either of the two spring type motor mounts in your picture would cracked the rear motor mounts during normal operation. Some other activity may have cracked them. One possibility is jacking up the engine without loosening the four rear motor mount bolts attached to the flywheel housing and removing one bolt from each side to relieve the pressure. I have seen mounts cracked that way, and there are other possibilities, too. It might not be the front motor mount.
 
I don't think you will like that mount!
We had a club member try one of the after market mounts like you have installed. He hated it! very soon he switched back to the original type mount. He has float a motor mounts at the rear.
Keep up the good work you do with Tillison carbs!
Herb Neumann
Concord CA
 
I have always wondered if something heavier like a valve spring would be more effective.

Since the flywheel and ****** are behind the rear motor mounts, it takes a lot of the load off the front motor mounts. Nothing heavier than what originally came is needed there for support. In fact it's neccessary to tighten the castle nut on the bottom to put some pressure on the bottom spring to pull the top springs down enough for the hand crank to line up properly through it's bearing and into the engine cranking nut.
 
Since the flywheel and ****** are behind the rear motor mounts, it takes a lot of the load off the front motor mounts. Nothing heavier than what originally came is needed there for support. In fact it's neccessary to tighten the castle nut on the bottom to put some pressure on the bottom spring to pull the top springs down enough for the hand crank to line up properly through it's bearing and into the engine cranking nut.

Tom,

How much should the bottom-nut be tightened ? Presently on my '28, the crank jaw is sitting below the center-line of the crank-bushing / spring clamp...

I've been blaming the two outer springs, but now I'm wondering if the bottom nut is too tight ?

SC Frank
 
Tom,

How much should the bottom-nut be tightened ? Presently on my '28, the crank jaw is sitting below the center-line of the crank-bushing / spring clamp...

I've been blaming the two outer springs, but now I'm wondering if the bottom nut is too tight ?

SC Frank

Yes, just loosen the bottom nut to see if the front of the engine will lift enough for the crank to slide right in. You may (should) have to loosen the rear motor mount bolts to allow the engine to lift without binding.

If the front won't lift up enough, then you may have to replace the top two springs. Seems I recall some people saying the replacement springs are a bit longer or stiffer than originals, but I'm not positive. The ones I've used have been fine.
 
Similar question over here. I'm currently running a slight drop to the front end of my 1930 Sedan. With the drop, the tie rod just hits the nut and stud that holds the front yoke to the cross member. Wondering if I could shorten the stud and run a small piece of rubber (grommet) instead of the spring to gain a little bit more clearance. What type of flex does that bottom spring take? Otherwise I was thinking of running the front float-a-motor mount since that would remove the stud. Curious on ideas or suggestions.

Thanks for the time!
 

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I have a 31 coupe with excessive vibration. It viberates sitting still and at just about every power setting. I noticed that the front mount spring seem compressed to the point that I could not get a piece of sheet metal to slide in between the couils on the spring. I loosened the nut but there doesn't seem to be enough space between the coils of the spring to provide any cushioning. Can anybody post what the height of the spring should be when the nut is completely loose (i.e. only the weight of the moter used to compress the spring).
 
I've seen mounts like that used before, but I thought the rubbers went between the frame and the mount...........
The picture was shot from a misleading angle! There IS large rubber pads between mount and crossmember, also rubber pads BELOW the crossmember. Trick is to enlarge crossmember holes, using a Harbor Freight Uni-Bit, to 1 inch in order for rubbers to "squish" into holes in order to insulate through bolt from touching crossmember. VERY smooth when installed in this manner. Original front mounting system is "VERY MICKEY MOUSE," but if you're a Purist, you're stuck with it!
 
The picture was shot from a misleading angle! There IS large rubber pads between mount and crossmember, also rubber pads BELOW the crossmember. Trick is to enlarge crossmember holes, using a Harbor Freight Uni-Bit, to 1 inch in order for rubbers to "squish" into holes in order to insulate through bolt from touching crossmember. VERY smooth when installed in this manner. Original front mounting system is "VERY MICKEY MOUSE," but if you're a Purist, you're stuck with it!

Are you still running a Model A flywheel housing and two rear mounts? It should work fine for some time in the flat lands but even then it will be interesting to see what happens to your hood fit as well as other potential issues over the next 5k or 10k miles!
 
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