Crank pulley removal...again

Tom Wesenberg said:
You can get by with running the bottom nut tight, after all, my 1928 has NO springs because the front of the engine is bolted directly to the crossmember.
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Tom,
Thanks. Your '28 with the engine bolted to the frame confirms my thought that tightening up the yoke nut would be the way to go for now. Is this standard for the '28? I would think you would have a good amount of engine vibration transmitted to the frame.

Postponing the work until winter gives me a chance to review the front float-a-mother mount suggested by Bill and TDO. Thanks to all for your help and suggestions.

Glen
 
Model A's had the solid front mount until November 1928. See page 294 in the SERVICE BULLETINS.
I don't really notice undue vibration from my solid mount.
 
Tom Wesenberg said:
Model A's had the solid front mount until November 1928. See page 294 in the SERVICE BULLETINS.
I don't really notice undue vibration from my solid mount.
Click to expand...

Tom,
First, sorry about the spelling error in my last post....it pays to be careful and check spelling.

Second, interesting that the '28 s had solid mounts....did not know that. Maybe my weird mount is not causing my vibration after all. Will confirm this when I get to tear the mount apart this winter. Thanks

Glen
 
I'm pretty sure this is the spring setup you have.

Bob
 

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There is precious little weight on the front mount, which is why the rear mounts are so massive. The front is more of a stabilizer, which is why Purdy et.al. say to not tighten the castle nut more than just enough to get the cotter in.
Your setup sounds way overtightened.

But if it has been that way, leave it alone until winter, or back the nut off as much as possible and try it and do not worry about the crank hole right now, your electric starter does work, right? Try it loose and see what happens. I seriously doubt it can do any harm loose, and in any event if there is less vibration then who cares what happens to it; it is obv. wrong.

If only a Model A could talk and tell you all the crazy mechanical violation it has suffered.......
 
If he has Float-A-Motor mounts in the back doesn't that take the "float" away from the front and makes it more like a solid mount because the the engine is now sitting on 3 points?
If the engine has vibrations I would think there is more to fixing it then replacing or tightening down the front mount.
The original rear mounts put the motor/tranmission at an angle, the front mount was as stated above, a stabilizer, the motor floated above but did not really rest on the front cross member.
 
Just a thought but I'm also thinking that the rear float-A-motor mounts may play in to the overall problem. If the rear of the engine is sitting too low, it will through off the angle of the crankshaft pulley and ratchet nut in relation to hand crank alignment . A couple of things to consider is, Are the rear float-A-motor biscuits too tight, hardened and squshed down too far? this would lower the rear of the engine. The rear mounts don't need to be too tight either or this can add vibration. Could the frame be slightly sagging at the rear mounts? Check the gap at the lower rear of the hood. If the gap is wide at the bottom and too close at the front, this will be a dead give away. If the torque tube is touching or nearly touching the service brake cross shaft, this is another indication of frame sag or problems related to the float-A motor mounts. Sometimes the rear parts of the float-A-motor mounts will be l;eft off and cause the rear of the engine and transmission to get out of proper alignment which will effect alignment at the front. The rear most part of the float-A-motor mount connects to the universal joint housing and a thick square rubber block with a metal piece attached with two bolts fit over the edge of the center crossmember and raises tand stabilizes the transmission and is a necessity for proper operation of the float-a-motor mount system. I use the front mount spring setup that Bob C pictures above without the rubber parts with a spring under the castile nut with good results. Just a few thoughts and areas to check.
 
The last several posts are very informative regarding my front mount. Yes, I think mine is the same as the spring unit posted by Bob C and the one used by Purdy. This leads me to think my setup is not just a shade tree mechanic fix as I thought but a real aftermarket device meant for the model A. Since Tom's '28 front mount is solid and Purdy uses the same mount as mine with no apparent vibration problems in either of their cars, perhaps my front mount is not the cause of my vibration after all.

Purdy has some interesting comments regarding taking a closer look at the float-a-motor rear mounts to make sure they are correctly installed and adjusted. I will do this after getting back home early next week. I'll leave the front mounts alone until reviewing the rear ones per Purdy's suggestions.
My gut feeling is that the front of a car motor should be able to float somewhat to help relieve the stress of rotational torque when accelerating and to absorb some of the movement of the engine caused by bumpy roads and hard braking. With that in mind, I'll look for a shorter spring than standard which will fit on the limited space on the yoke stud and leave the current large upper springs alone for now until I can put some miles on the car and see if there is any change in the vibration level.

These posts have been very helpful for me in understanding the first thought about a solution to a problem may not always be the correct one and that one should think more about other possible actions to take before charging ahead. While I still am not sure what is causing my vibration problem, the input from others has led me to look at more than one possibility. Thanks for the input from all.

Glen
 
Purdy Swoft said:
Just a thought but I'm also thinking that the rear float-A-motor mounts may play in to the overall problem. If the rear of the engine is sitting too low, it will through off the angle of the crankshaft pulley and ratchet nut in relation to hand crank alignment . A couple of things to consider is, Are the rear float-A-motor biscuits too tight, hardened and squshed down too far? this would lower the rear of the engine. The rear mounts don't need to be too tight either or this can add vibration. Could the frame be slightly sagging at the rear mounts? Check the gap at the lower rear of the hood. If the gap is wide at the bottom and too close at the front, this will be a dead give away. If the torque tube is touching or nearly touching the service brake cross shaft, this is another indication of frame sag or problems related to the float-A motor mounts. Sometimes the rear parts of the float-A-motor mounts will be l;eft off and cause the rear of the engine and transmission to get out of proper alignment which will effect alignment at the front. The rear most part of the float-A-motor mount connects to the universal joint housing and a thick square rubber block with a metal piece attached with two bolts fit over the edge of the center crossmember and raises tand stabilizes the transmission and is a necessity for proper operation of the float-a-motor mount system. I use the front mount spring setup that Bob C pictures above without the rubber parts with a spring under the castile nut with good results. Just a few thoughts and areas to check.
Click to expand...

After checking over my float-a-motor rear mounts, Purdy is right. The rear part of the mount that connects to the universal joint housing is missing on my car. The mounts themselves seem to be in good shape. I can dent the biscuits with a fingernail so the rubber is not hardened and the bolts are only about a turn or so tight and just starting to compress the rubber.

I suspect this is the cause of my excessive engine vibration and not the front mount as I thought. Probably also the reason the front of the motor won't compress the same springs Purdy uses enough to get the lower spring on the yoke stud between the castle nut and the front X member.

Would appreciate comments anyone might have on these thoughts and, also, where I might be able to find the missing rear part of the float-a-motor system. Maybe I'll have to bite the bullet, buy a complete new float-a-motor system and replace all of the components.

Glen
 
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