Front spring shackle bushings

[Tom Endy]

Can someone explain why there are two different outside diameter size shackle bushings for the front spring and perch in the Model A kingdom. A few years ago I rebuilt several Model A front ends. I ordered replacement front shackles from Bratton's. They arrived with bushings that were thin wall and too small in diameter and did not fit the inside diameter of the boss in the spring and the perch.

What was needed was a shackle bushing that was the same outside diameter as the rear spring shackle bushings. What I finally did was order a dozen or so rear shackle bushings from Bratton's and had the length cut down.

The bushings that came with the front shackles were discarded and I used my supply of shortened rear shackles bushings on several front end restorations. The problem was solved.

Currently I am working on two front ends and both require the thin wall bushings in both the spring and the perch. My cut down rear shackle bushing are too large in diameter to fit the spring boss and the perch boss. The diameter of the shackles themselves are the same, it is the inside diameter of the bosses on the spring and the perch that are smaller.

The outside diameter of the thin wall bushings are a nominal 0.690. The outside diameter of the thicker bushings, the ones that are the same outside diameter as the rear shackle bushings, are a nominal 0.753.

What gives, has it something to do with year models?

Tom Endy

 

[Steve Plucker]

What gives, has it something to do with year models?


I doubt it...The number given in the Parts Price Lists from 1928-1931 is A-3034.

Not many changes to the bushing were made...Looks like just one on November 26, 1928 but what ever that was you will have to get the Part Releases or the Part Drawing from the archives.

What do the outside diameter of the originals for which you removed measure? I do not think they would of changed.

Are you working with original or reproduction perches?...Original or reproduction springs?

Pluck

 

[pat in Santa Cruz]

I noticed the same thing, Tom. The thin bushings are only applicable on rare occasions, so I suspect someone used measurements from an old repro they thought was original when they made those bushings. The majority I have changed used the larger ones. They should be the same diameter as the rears on an original perch

 

[Tom Endy]

I noticed the same thing, Tom. The thin bushings are only applicable on rare occasions, so I suspect someone used measurements from an old repro they thought was original when they made those bushings. The majority I have changed used the larger ones. They should be the same diameter as the rears on an original perch

I agree, however, what I am saying is I have a car I am working on ( un-molested early 30 town sedan) that has both the spring boss and the perch boss of a size that requires the thin wall bushings. I also have another spring that also requires the thin wall bushings. The bushings I removed measure .690 and there is no way I can install the larger bushings that measure .753 that I have used in the past and are the same diameter as a rear spring bushing.

Tom Endy

 

[pat in Santa Cruz]

I agree, however, what I am saying is I have a car I am working on ( un-molested early 30 town sedan) that has both the spring boss and the perch boss of a size that requires the thin wall bushings. I also have another spring that also requires the thin wall bushings. The bushings I removed measure .690 and there is no way I can install the larger bushings that measure .753 that I have used in the past and are the same diameter as a rear spring bushing.

Tom Endy

ah, now I get it. That seems like a question only Marco or Pluck might know, if anyone. Since Brattons came out with those bushings, maybe Walt knows the story behind them

 

[MartyAndrew]

Rather than start a new thread I'm going to add onto this similar one that I found on a search.
I bought front shackles for my '29 Coupe from Brattons. In my case, the bushings that came with the shackles fit loose on the shackle bolts. However I also bought 2 bushings as 'extras' since I had to do some perch bore repair, and thought I might damage some. The extras I bought individually have a slightly larger OD than those furnished with the shackles (.689" nom vs. .682" nom), and a thicker wall (.055" vs. .042"). See the video I posted on youtube:
http://www.youtube.com/watch?v=bOH9RUfu5f0
So my question is, which are the right fit? The extras I bought seem to fit the way I'd call "right" but why would Bratton's supply thin-wall bushings that are too big for their shackle bolts?

Marty

 

[Tom Wesenberg]

Rather than start a new thread I'm going to add onto this similar one that I found on a search.
I bought front shackles for my '29 Coupe from Brattons. In my case, the bushings that came with the shackles fit loose on the shackle bolts. However I also bought 2 bushings as 'extras' since I had to do some perch bore repair, and thought I might damage some. The extras I bought individually have a slightly larger OD than those furnished with the shackles (.689" nom vs. .682" nom), and a thicker wall (.055" vs. .042"). See the video I posted on youtube:
http://www.youtube.com/watch?v=bOH9RUfu5f0
So my question is, which are the right fit? The extras I bought seem to fit the way I'd call "right" but why would Bratton's supply thin-wall bushings that are too big for their shackle bolts?

Marty

I did the same thing 20 years ago. The extra bushings were a perfect fit with the shakles from the kit. It costs extra money, but at least the fit is right. I also don't know why the extra bushings would be different than the kit bushings.

 

[Mike V. Florida]

Make sure that Bratton's is aware of your findings.

 

[Tom Endy]

My thanks to those who responded to my question. It appears that no one has a conclusive answer to the question. My experience over the years has shown me that there are two different size front spring perch inside diameters out there in the Model A kingdom. One version requires a spring perch bushing with the same larger outside diameter as is the rear spring perch bushing. The other version requires a thinner bushing. The bushings that come with a set of front shackle bolts are usually the thinner version. To accommodate the front perch that requires the thicker bushings I purchased a couple dozen rear shackle bushings from Bratton's and had the length cut down. In this manner I am able to accommodate whichever version show up for overhaul.

Tom Endy

 

[MartyAndrew]

Oops, in checking my invoices, I found the shackles were from Snyder's not Brattons. I had just stored them in a larger Bratton's box. Will contact Snyder's and let them know.

 

[MartyAndrew]

…and one last follow-up, Snyder's was really helpful. The guy couldn't explain the incorrect sizing but offered to send the bushings that fit well, at no extra cost. All set.