1930 Essex vibration at higher speed

[stev1955]

 1930 Essex with the 161c six L-head engine. After working on the carburetion of this engine for quite awhile I finally have it running better than it has for some years. Having done that, one problem I've always had with this car is I've never been able to go over 30 mph as I get a vibration that makes you want to take your foot off the accelerator. I'm not sure it will go a whole lot faster with the rear end ratio they had in these cars back then, this one is 5.1 to 1. I'm just hoping to just feel more comfortable at maybe 35-40. I have noticed the vibration in the steering wheel in general but it does not oscillate back and forth. But I also feel it in the seat. Pushing in the clutch does not affect it, still there. I replaced the kingpins recently with no play. I had a driveshaft with modern universal joints made also some time ago. So I'm hoping someone can steer me in the right direction on what could be th most likely culprit. Wheel bearings, axle bearings, unbalanced tires, transmission? It's approaching miserable in my unheated garage so I don't know how much time I have left to look into this but whatever guidance I can get is great.
 

[JFranklin]

Well, you have proven it isn't from the engine. Was the driveshaft built by a driveline specialist? If you feel it in the steering, look at tire/wheel balance and trueness. 

[paulrhd29nz]

Check u joints are not parallel with each other. Did you get rid of the Spicer joint?

[keiser31]

Check front end alignment, too.

[stev1955]

Thanks everyone. The driveshaft was built by a shop that does trucks of various sizes so I'm hoping there is no problem there. but I will check to see the if the  universals got aligned wrong over time of taking in and out. I have not checked the toe lately buf it was at 1/8" toe in last I checked. Paulrhd29nz I kept the original driveshaft.

Edited December 20, 2021 by stev1955 (see edit history)

[JFranklin]

I'm not sure what Essex calls for but 1/8" toe in seems excessive. My Ford is 1/32".

Edited December 21, 2021 by JFranklin (see edit history)

[Grimy]

My 1920s and 1930s Pierces specify 1/8 to 1/4 but are a lot bigger than Ford and Essex.

[Bloo]

How many u-joints in this driveshaft? Same as original? What sort of angles do they run at?

 

[Oldtech]

In my mind an out of balance or out of round wheel/tire would be the most likely. can you tell if the vibration is same speed as motor when in third gear?  if it's not motor speed then wheels. 

[JFranklin]

1 hour ago, Oldtech said:

I can you tell if the vibration is same speed as motor when in third gear?  if it's not motor speed then wheels. 

In the post he said he disengaged the engine from the equation.

[stev1955]

The car has 2 universals on the driveshaft and I really don't know the angles they run at but I will check today if the universals  are out of alignment. I don't remember ever taking the yoke off the driveshaft but maybe I did and put it back out of sync with the rear. An out of round tire could be a possibilty too but how would you check for that if it's not visible to the eye?

[john hess]

find a smooth stretch of road with a down hill grade..  get up to speed, get out of gear, drift to a stop.... note any changes and at what speed they occur... report findings. I'm thinking flat spots on tires.. my new bias tires take smooth out after they warm up... Cold weather takes a little longer to notice change... John 

[Alfa]

Misalignment of the drive shaft universal joints was a good suggestion, but it sounds like you have checked that now. Problems can arise if the sliding joint was pulled right out and then replaced a few splines out from where it should be.

 

That aside, I would be suspicious of wheel/tyre balance and if the tyres are old, of some out-of-roundness. A simple check would be to jack up each wheel in turn and spin the wheel looking for any lumps and bulges or irregularity of any sort. Balancing is probably best done with a balancing machine at a tyre fitting shop, but you could do a pretty reasonable static balance by using a front hub and spinning each wheel in turn (provided the brakes don`t bind at all) and observing if the wheel stops in the same place each time, or in any position. Add weights until it will stop anywhere.

 

Let us know what you find.

 

Adam.. 

[trini]

Unbalanced tires will run smooth up to certain speeds , then Wham, vibrations. Above vibrations the wheel will smooth out again. 

[JFranklin]

I had an early Mustang that had a balance problem. I spent a lot of time and money trying to locate why. Tires and wheels were checked for true and balance. The driveline was rebuilt, and balanced twice. We even replaced the flex plate in the transmission and still the problem persisted. I finally found a mechanic that resorted to using a hose clamp and a bolt on the driveshaft, moving it a small amount around between test drives. He got rid of all the vibration. He said it was coming from somewhere besides the driveshaft. His fix was there when I finally sold the car. I did tell the new owner that although it looked funky, not to mess with what looked like a farmers fix! True story and I still can't figure where the vibration originated from.

Edited December 21, 2021 by JFranklin (see edit history)

[stev1955]

Okay I checked the driveshaft and the builder had marked it with yellow paint and it appears to be in alignment.

 

 

 

I jacked up the front and stuck a magnetic light on the frame on the drivers side, and spun the left front tire and sure enough there was a flat spot maybe 3/16 deep in one spot. Before and after pics.

 

 

Also did the right front and it was the same, maybe 3/16 deep flat spot. I didn't do the rears because it was 25 in my garage and I hate the winter. But I see no reason they would be any different as I got them all at the same time. Would this be enough to cause such a strong vibration?

[JACK M]

If you look at this pic of the underside of one of my hot rods you will see a cast iron piece on the driveline that is just behind the front yoke.

This was from a donor car, a 68 Chrysler wagon and that cast piece is permanent and cannot be adjusted or easily removed.

This drive line was checked for balance by three different shops. 

I changed pinion angles several times, measured EVERYTHING many times.

Tried a different third member, tried a different transmission.

T tried everything that I could think of to rid myself of a vibration.

I could get it to do different vibration patterns but never could get rid of it.

I had convinced myself that it had to be something about that driveline as it was the only part in common with all efforts.

So, I took it to one of the shops that told me there was nothing wrong with it and told them to replicate it without that cast piece on the front.

Also I want all new U-joints and a new yoke.

Viola, three or four years of frustrations were gone.

I have no idea about why Chrysler put this weight on the front of their drivelines but it is what was causing my problem.

I have since seen several of this same driveline under Chryslers and owners tell me they have no problems.

Just goes to show that even perfect parts can be defective.

 

[JACK M]

My comment on your vibration,

I can usually tell if its the speed of a drive shaft or the speed of a tire.

A drive line vibration is the rattle your teeth kind whereas a tire is more like shaking your belly.

[stev1955]

I understand what you mean driveshaft spins alot faster than a wheel

[stev1955]

I have the car up on four jack stands at the present time, if I ran it up to speed would that show anything....or is that even safe?

[john hess]

flat spots don't necessarily mean out of balance, but if run too much will cause cupping all around tire... if you don't drive the car for long periods of time, I would leave it on jackstands.... 

 

put a blanket over the tire and a light bulb on the floor overnight.... warm the tire up and check in the morning to see if it 'rounds' back out...... 3/16 will definitely give you the shakes when driving.... John 

[viv w]

Driveshafts need to have proper alignment, as shown with the 2 arrows,  but that is provided the guy assembled it right before marking it.

 Check your shaft to see if it has had any lumps of metal welded onto it for balancing.

 It is my guess that the guys who made up your new shaft, either forgot to balance it, or do not have a driveshaft balancing machine.

[49-P15]

Unlike modern cars where the steering box pitman arm is connected to both wheels.  these old boats (I had a 1930 Chrysler) steered the driver's side wheel and the right wheel was connected to the left one through several joints.   Play and sloppiness in any one of these joints or the sum of all may leave the right wheel able to vibrate.   You might see if the right wheel behaves differently from the left.

[Oldtech]

6 hours ago, stev1955 said:

Okay I checked the driveshaft and the builder had marked it with yellow paint and it appears to be in alignment.

 

 

 

I jacked up the front and stuck a magnetic light on the frame on the drivers side, and spun the left front tire and sure enough there was a flat spot maybe 3/16 deep in one spot. Before and after pics.

 

 

Also did the right front and it was the same, maybe 3/16 deep flat spot. I didn't do the rears because it was 25 in my garage and I hate the winter. But I see no reason they would be any different as I got them all at the same time. Would this be enough to cause such a strong vibration?

 I would say yes.  There will be times that both wheels have the highs and lows in sync.  that can make it worse. Not sure at what speed though. would have thought faster. 

[Grimy]

If I read your initial post correctly, you say that this is a longstanding problem.  Have you lifted one front wheel at a time and shaken it, up and down, left and right, looking for movement?

 

Over ten years ago, a friend had a Death Wobble at about 38 mph in a recently acquired 1930 Pierce long wheelbase.  I diagnosed the issue as the following:  Correct inner front wheel bearing seals for these cars are unobtanium: a felt wiping seal within a metal housing, outer lip of the housing fits into a machined recess at the outside of the hub.  A common "fix" of yesteryear was to fit a more available felt seal of the same ID size, whose metal housing's OD is smaller diameter than the original , into a larger "carrier" (my terminology) made of fairly-soft red plastic (National brand, I believe) whose OD matches the OD of the large-diameter hub.  In this particular case, the machined recess in the hub was not deep enough to fully accept the lip of the plastic carrier.  Accordingly, the reinstallation of the hub and drum assembly could not fully seat against the base of the spindle, and tightening the spindle nut before backing off for the cotter pin could not achieve tightness.  Shaking the jacked-up wheel displayed the looseness.

 

Choices, all unappealing, were (1) machine the groove in the hubs deeper so that the lip on the plastic carrier would fit entirely into the groove/recess, or (2) attempt to trim the depth of the lip perfectly even around its circumference, or (3) search for another carrier piece with the same dimensions but with a shallower lip.

 

My friend had the work done--whatever it was--at the dealer who sold him the car.

[Hudsonite]

So I have a 1934 Terraplane and a buddy of mine has a 1929 Essex.  I can assure you that your car is a 45-50 mph cruise speed vehicle.  I cruise about 55-60 with mine as I have a stock 4:11 rear.  You’ve been given some good guidance on locating the issue in your drive train.  Tires do get flat spots from sitting, checking all of your wheel bearings and races, alignment check, etc are all good places to start.  I would only suggest that you approach it methodically to narrow it down.  Do the easy things first and keep checking after each tweak to see if it improves will eventually point you to the source of the vibration. 

[Bud Tierney]

If your garage was 25 degrees and the car'd been sitting (tires cold) when you measured your flat spots they were probably ly normal---but unless you have old or unusual tires flat spots should eben out in a few slow blocks to a mile or so...

You didn't say (unless I missed it) if the vibration with the new driveline was TXACTLY the same as with the old...

You can also ckeck tires by jacking them up, spinning rhen and lighty letting your gloved fingertips brucsh the moving tire sidewall and tread--irregularities show up quickly

Also, did I muss that after warming up the tires, you tried swapping the wheels around??

[nsbrassnut]

Hi All

 

And one that could cause a similar effect. A worn out front wheel bearing race. Bearing races can start to spall and fail with age, especially if over tightened.

 

I had a vibration issue with a '36 Packard 120 and was convinced it was occuring at the front U-joint when it felt like the vibration was from under the floor. Later with the front wheels jacked up and rotating them with a finger on the steel wheel you could feel a very fine "roughness" like there was sand in the wheel bearing. I took out the bearings and found pitting in a bearing race.

 

Replaced all the front wheel bearings, adjusted them per the manual and the vibration went away.

 

And it was a vibration that you could really feel when driving, all out of proportion to what it turned out to be from.

 

Jeff

Nova Scotia

[stev1955]

Thanks to everyone for the ideas. I found I do have play in my steering box. I grabbed each tire and tried moving them in all directions. No movement in the rears and in the front I do get movement side to side and I can see the pitman arm moving maybe approaching half an inch. So that's my next step to adjust that. Pretty sure tie rod is good. The tires are Universals and maybe 10 years old so I'm hoping they are not bad and maybe will even out, as you can see by the tread in the pictures we don't put much miles on it. No heater in the car so I usually put the cover over it for the next couple months. Will check out various things when possible. Thanks

[Hans1]

 

 

 

 

[Hans1]

 

What  type of wheel, wood spoke or wire?

 

Please check runout, verticle and horizontal when spinning.  One possibility is crabbing, where tire jumps sideways, scraping tred as it regains forward motion when driving.

 

also check out of round on "wheel fellow" on wood wheels, and tire mounting rim.

 

Your mention steering arm movement, the arm should have a round ball, that is cupped in end of drag link by two ball cups that are spring loaded.  Pre load is by the threaded plug on the end.   

 

Check both ends of drag  link pre load.

 

Your car origionally had double acting shocks, are they demonstrating same resistance to movement at end of shock arm?

 

The shock arm is connected to axle with a short drag link connector.  The link has rubber dampened cuped ends that cause the metal ball end to wear flat, on both ends.  Problem.

 

Chassis springs may be broken in the middle leaf,  and lubrication may not be uniform on both sides.  The lube might be too slippery.

 

Best wishes for the New Year

[Grimy]

1 hour ago, Hans1 said:

The link has rubber dampened cuped ends that cause the metal ball end to wear flat, on both ends.  Problem.

Have an assistant hold the steering wheel while you shake the LF wheel (if LHD) and watch for movement (or lack thereof) at the ends of the drag link.  If replacement ballstuds are not readily available, it is possible to scribe marks on the end of the stud portion, then after removing and cleaning and lubricating the ball studs, turn the studs 90 degrees so that the unworn portions of the balls now become the wearing surfaces.  That is, the scribe mark should now be 90* out from the way you found it.  It's a good idea to service the drag link pivoting components anyway, even if it is not the cause of the current problem.