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Old 02-07-2012, 05:03 AM   #1
SAJ
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Default roadster front spring problem

I have an early RHD 1930 standard roadster, which someone tried to turn into a deluxe in the 1990’s. The front spring it came to me with allowed the draglink to rub on the tie rod and the shackles were grounding on the axle, with some wear evident on all items which touched. The shackles were rubber-bushed. I removed the spring with the intention of re-arcing it cold, but found the measurement between the eyes was already smaller than new specification by a small amount and the arch height was 5-3/4 inch as specified . So I bought a new “premium” roadster spring from Snyders and fitted it with new non-rubber shackles and gaiters, after lubing it with moly disulphide paste (applied as a liquid in Shellite solvent).
This was about 5000 miles ago, and I have since gone through a set of new M&S shocks and now have a set of new Bill Stipe shocks, which seem very nice indeed.
But my ride still seems like the shocks are far too stiff, no matter where I set them.
In looking closely, I see that the shackles just clear the axle, but the left hand one is hard up against the left wishbone fork at rest and the right hand one only just misses.
This means the spring cannot flatten, and my suspension movement is limited. Both shackles still seem too close to the axle to me too – maybe .030 inch clearance underneath, at a guess.
When I fitted the new spring I was surprised that it was the same length between eyes as the old one, and same arch height too, but I assumed the new spring rate would be greater and my old spring had lost stiffness in some way. At the time I was overhauling the whole car before a long rally, so did not pay much more attention to the spring fit.
The rubbing drag link went away when I fitted a shorter pitman arm, before this rally. However, I am now chasing more compliant, less choppy suspension, though I have never ridden in another roadster to compare it.
Can anyone help with advice on what may be wrong, please, or what I can do to regain the lost clearances? I have attached photos showing the clearances from underneath and in front of the car the car. Thanks in advance. SAJ in New Zealand
Attached Images
File Type: jpg LH shackle contacts wishbone.jpg (33.0 KB, 193 views)
File Type: jpg RH shackle contacts wishbone.jpg (38.0 KB, 203 views)
File Type: jpg RH shackle contacts wishbone2.jpg (59.2 KB, 248 views)
File Type: jpg view ofLH suspension.jpg (68.5 KB, 209 views)
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Old 02-07-2012, 05:55 AM   #2
MN Stumpjumper
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Default Re: roadster front spring problem

Defenately not right, You need to do some measuring. The spring shakles should be at a 45 degree angle when loaded. Wrong axle perhaps?
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Old 02-07-2012, 06:06 AM   #3
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Default Re: roadster front spring problem

SAJ Couple of thoughts. It may have something to do with spring shackle or perch (or a combination). You didn't say if you replaced shackles. So my commnets are based on if you didn't. If you have access to an original shackle measure the center to center dimension & compare it to the the shackles you installed, if installed ones are wider that will lower the spring, also the bolt diameter if you reused them they might have been worn. If not that how much wear was there in the spring perch bushing hole? Any wear could lower the bushing & in turn the spring eye. Were shackles snug in bushings? There is not a lot of clearence between spring & axle to begin with so when you add up wear of different components it dosen't take much to touch. Also urethane bushings will compress some as well. If not any of the above are perch axle to center of perch spring bushing hole height dimensions correct. Axle perch holes ovaled so perches aren't centered on axle? Good luck. Tim
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Old 02-07-2012, 08:54 PM   #4
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Default Re: roadster front spring problem

On the RH photo,the brake shaft hsg appears to be not far enough into the king pin ball.This suggests that the perch has sagged.You should be able to put your finger between the spring eye & perch & have at least 1/8 to 1/4"under spring to axle.The rust dust under perch makes me think the perch is loose in axle as well.
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Old 02-07-2012, 09:28 PM   #5
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Default Re: roadster front spring problem

You may have something there columbiA, the shock link looks out
of line also.

Bob
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Old 02-07-2012, 11:29 PM   #6
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Default Re: roadster front spring problem

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Thanks MN Stumpjumper. The axle seems just like other Model A ones I have seen. Are there different versions of this axle? I thought they were all the same throughout Model A production. If not so that adds an interesting variable.
Tim B. The shackles and pins are new replacements sent with the new spring from Snyders. The Bushings are new too and a tight fit in their housings. Shackes are the same measurements as old ones I have. The old bushings were black rubber that I removed, leaving the perch eyes unworn. Perches are tight in the axle, holes not oval.
I am not sure what your "perch axle to centre of perch spring bushing hole height" means, and my car is not with me now, but I will look at this tomorrow, but I probably need another set up to compare it with.
I will contact Tom Jordan at Snyders and see what he suggests if there are no other obvious things that I may have done or could do, other than re-arching the new spring cold. Does this work as a permanent cure? I see it in Les Andrews' book, but my instinct tells me that re-annealing, resetting and re-hardening/tempering is the real answer. And then only if we have good quality spring steel to start with.
Hopefully someone else may chime in with more experience on my problem.
SAJ in NZ
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Old 02-08-2012, 12:01 AM   #7
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Default Re: roadster front spring problem

Thanks Columbia. I think you may be right. I have been watching the fretting corrosion coming out of the perch bolt, but the bolt seems very tight in the axle and I could not budge it last time I tried. I guess it must be working in the axle though, from all the rust emerging. This has happened quite suddenly, so who knows what I may find when I dismantle it and have a look. I bought a car when I was a youngster that had its kingpin bushes repaired with epoxy, which was new on the market in the early 60's. After only a few miles the kingpins went from tight to worn out and I sold the car. "Farmers" fixes last a lot longer than that! I hope this is the answer and it is just a matter of restoring the fit in this area . I see, too, that the shock link lies at an angle as BoB C points out
Regards to all who answered. SAJ in NZ
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Old 02-08-2012, 12:14 AM   #8
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Default Re: roadster front spring problem

SAJ,
Looks like your spring may be a little long..mabe an inch ! Mabe perch bolt holes worn out too, but spring , new or not, looks long. If an inch shorter, then when it is 'spread' , shackles should ...reach out to connect and NOT go back against perches when spreader removed and car weight put on ?
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Old 02-08-2012, 01:19 AM   #9
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Default Re: roadster front spring problem

Something's wrong, and I'm guessing it's not the spring. You have two now with the same dimensions and the same problem. I put a new Snyder's spring on my roadster a few years ago, and it works fine. It seems crazy, but I wonder if your Perches are bent. Maybe someones idea of how to lower the car.
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Old 02-08-2012, 01:33 AM   #10
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Default Re: roadster front spring problem

I have re-arched springs cold.I take them apart & set one leaf at a time on edge on the concrete floor & draw the curvature of the leaf on the floor.Then take a short piece of 5 or 6 "channel iron & working the leaf back & forth across the upturned sides of the channel,beat on it with a 4 LB hammer.Check every so often until the curve is 1" to1 1/2" taller.The short leaves dont need to be done as much.Ive had good luck doing front springs this way.
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Old 02-08-2012, 05:41 AM   #11
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Default Re: roadster front spring problem

Many thanks to you all. Tomorrow I will see if the perches come out easily and report what I find. Hardtimes, the old spring was 30-3/16 inches between the centres of the shackle pins (i.e bush eyes) when removed from the car and the arch was 5-19/32 high to the bottom. I recorded the new spring as the same at the time, before fitting it. This length is what Les Andrews specifies as correct in his book.
I will explore Geo H's idea, but I reckon the axle holes are flogged out. Columbia's 1 to 1-1/2 inch is helpful too. If I re-curve them this is a good guide.
Thank you all very much for your replies and advice.
Regards
SAJ from NZ
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Old 02-08-2012, 07:52 AM   #12
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Default Re: roadster front spring problem

Looks like your perch pins are to deep into your wish bones and the spring looks to wide. JMHO.
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Old 02-08-2012, 04:03 PM   #13
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Default Re: roadster front spring problem

Quote:
Originally Posted by SAJ View Post
Many thanks to you all. Tomorrow I will see if the perches come out easily and report what I find. Hardtimes, the old spring was 30-3/16 inches between the centres of the shackle pins (i.e bush eyes) when removed from the car and the arch was 5-19/32 high to the bottom. I recorded the new spring as the same at the time, before fitting it. This length is what Les Andrews specifies as correct in his book.
I will explore Geo H's idea, but I reckon the axle holes are flogged out. Columbia's 1 to 1-1/2 inch is helpful too. If I re-curve them this is a good guide.
Thank you all very much for your replies and advice.
Regards
SAJ from NZ
SAJ,
Well, by process of elimination, i.e.- you've replaced spring/shackles/bushings and state that perches are OK.
Now that leaves the condition of the axle (bent/not) and the spring.
Yes, I say the SPRING because...it wouldn't be the first defective repro part that is not correctly made (arched) for the application.
At this point, I'd be focusing on the axle for proper shape !
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Old 02-08-2012, 04:23 PM   #14
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Default Re: roadster front spring problem

I'm thinking the same as Jim in post #12.

SAJ, what is that bolt in the front crossmember? Maybe a bolt for some repro front motor mount?
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Old 02-08-2012, 05:55 PM   #15
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Default Re: roadster front spring problem

check the axle to see if perch center to perch center is 37"
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Old 02-08-2012, 06:18 PM   #16
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Default Re: roadster front spring problem

Something is wrong with that spring, the shackles should be more horizontal. The way is now the axle can pendul-ate causing weird steering control. I've done a few springs from Snyder's and they were fine but they were not exact repro, more like driver replacement.
Did you try to communicate with Snyder's?
GW
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Old 02-09-2012, 12:31 AM   #17
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Default Re: roadster front spring problem

I dont know if current repop perches are any better,but back in the 70,s they were made of cast iron & were thicker looking than the original forged steel ones.They would bend easier than the originals.I dont think the repop perches & shackles would have stood up to the pounding they had to endure on the washboard roads of the day.Even in the 50,s there was very little pavement in our area.As for the perch,just because the nut is tight doesnt mean its not loose.On my car I could not tighten or loosen the nut even with heat,so I had to carefully slice off both sides of the nut & knock off the other 2 sides with hammer & chisel,& the threads were OK.There was a slight space between axle & RR,so I notched a couple king pin shims to slip in place & used a new nut with some anti-sieze & sucked it up tight. Another problem you might have with the brake shaft hsg not in far enough,is that the push rod for the brake wedge may bind or bend inside the KP & make that brake slow to release.
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Old 02-09-2012, 03:18 AM   #18
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Default Re: roadster front spring problem

Thanks for all the helpful info. I removed both perches today. They came out with a bit of a tap and wiggling. There was rust on them and some bright marks on the top tapers, but they were not really loose. A few thou wiggle when just held down by hand but none I could induce with levers etc when cinched up tight again without the shackle in place. I think they are OK and, even though the nuts were really tight (probably 120 ft-lbs at least), I think that was corrosion and they will go up much more snug when I clean lubricate and refit them.
The “new” spring, whilst still clamped with the centre U bolts has 5-1/8 arch and 31-3/8 between eye centres. This is on the outer (loose) limits of the specs I have. The old spring is tighter with 5-3/8 and 30-13/16 inches. Maybe the centre U bolt is flattening the new spring a bit. I will see when I remove it.
Moving on to the axle question, in elevation it has 2 inches drop at the centre, measured from the ends, excluding the small bosses the kingpins fit on top of.
If this is bent it would cause the perches to lean in as suggested.
I am not sure which distance to measure across the perches, but I have 37.2 inches across the bolt centres at the bottom – agreeing closely with Roundvalley
The distance across the perch shackle eyes seems more significant and I have 33.94 inches, with the shackles out (i.e. no spring tension). I will reinstall the shackles and spring tomorrow and measure distances with load on the perches both inwards and outwards and see if they move, but I doubt it. That is, with axle hanging from the spring and wheels off the ground, and the reverse, car body fully loaded and supported on the springs.
That leaves a weak or too-long spring, bent perches, over-bowed axle or… what else?
I wonder if the perches ARE too deep into the wishbone yokes, which is what Jim and Tom suggested – if they have chewed their way into the tapers with fretting corrosion over a long period of time?. There are several spare threads at the bottoms under the nuts and more on one side than the other. I will check in the morning. If so I can turn up hardened tapered spacers to fix this, but the brake shaft housings will then be a little out of line, I suspect.
Columbia, my perches are both forged not cast.
Tom , some bolts are rivet replacements because the cross member has been in an accident at some time and refitted with 5/16 bolts. The more central one is indeed an aftermarket bonded rubber engine mount the car came to me with. I have the proper forged mount and new springs and will fit them while the front is off to see if it improves vibration on the overrun.
Thanks a million again guys. I may have several things adding up to the problem as suggested I think.
SAJ in NZ
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Old 02-09-2012, 05:34 AM   #19
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Default Re: roadster front spring problem

Someone needs to post a picture of a good setup. Unfortunately I don't have a picture and can't take one off my worn temporary front end.
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Old 02-09-2012, 10:00 AM   #20
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Default Re: roadster front spring problem

Is there another axle handy or a set of perches nearby that you can compare yours with?? It looks/sounds like your perches are sitting too "low" in the axle, or your axle is bent down in the middle although your measurement for perch spacing appears correct.
Paul in CT
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Old 02-09-2012, 10:54 AM   #21
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Default Re: roadster front spring problem

If I remember correctly the with of the spring should be 3" shorter than the perch bushing holes. Center to center. Here is a picture of my 31 tudor that is worn and needs bushings, a new spring and maybe new perch pins if the bushing holes are egg shaped. Please notice the nut on the bottom of the perch pins. Yours are driven up past the cotter pin holes. I would completely disassemble the axle, start from scratch and check all measurements, replace all worn parts. This front end has never been apart. IMHO
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Old 02-09-2012, 04:17 PM   #22
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Default Re: roadster front spring problem

Quote:
Originally Posted by Tom Wesenberg View Post
Someone needs to post a picture of a good setup. Unfortunately I don't have a picture and can't take one off my worn temporary front end.
Tom,
fROM 'someone' This rebuilt frontend has about 1200mi on it to date. '30 roadster.
Attached Images
File Type: jpg 100_1878.jpg (66.1 KB, 74 views)
File Type: jpg 100_1881.jpg (65.3 KB, 66 views)
File Type: jpg 100_1884.jpg (56.2 KB, 69 views)
File Type: jpg 100_1885.jpg (50.7 KB, 65 views)

Last edited by hardtimes; 02-09-2012 at 04:53 PM. Reason: add...
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Old 02-09-2012, 05:00 PM   #23
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Default Re: roadster front spring problem

SAJ
I just added some pics of my 'rebuilt' front/spring setup. If you look closely, you can see where my spring eyes bottomed/rubbed on top of my axle..prior to rebuild.
I now wondering....are your shackles repop...as they look longer than those I used?
LONGER , than stock, would not be good with same spring length as stock!
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Old 02-09-2012, 06:36 PM   #24
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Default Re: roadster front spring problem

Hardtimes, good point about the shackle length. Mine is 1 9/16" and I wonder what SAJ's are? That could help the bottom clearance, but the side clearance also looks to be too close.
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Old 02-09-2012, 07:39 PM   #25
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Default Re: roadster front spring problem

I'm of the opinion that the perches do look a bit low, but I really think that main leaf is too long. If a shorter leaf is fitted and the shackles are at the approximate 45* angle the clearances will be better. Center of axle bent? No way, your camber would be way off if that were the case.

SAJ, I just went back and looked at your photos again. In the very first photo it looks like the fillet at the top of the taper on the perch is visible above the wishbone yoke. It's hard to tell from the camera angle. If it can be seen then I bet the perches are at the correct height.

Last edited by Fordors; 02-09-2012 at 07:52 PM.
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Old 02-09-2012, 07:47 PM   #26
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Default Re: roadster front spring problem

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Quote:
Originally Posted by Tom Wesenberg View Post
Hardtimes, good point about the shackle length. Mine is 1 9/16" and I wonder what SAJ's are? That could help the bottom clearance, but the side clearance also looks to be too close.
I second that...again. I got my shackles from a ole model a expert. He told me that they were stock..from his stash. SAJ's just look tooo long. If they were proper length i.e.- shorter, the spring and shackle would have to 'reach' out further to mate and that should do it. They look repop..no
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Old 02-09-2012, 09:33 PM   #27
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Default Re: roadster front spring problem

jimvette59 Someone has had your front axle apart at some time in its life because the KP lock pins are in backwards!The steering stops should be on the back side.
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Old 02-09-2012, 11:27 PM   #28
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Default Re: roadster front spring problem

Wow! I've started something. This technology is amazing though, that we can interchange stuff so quickly. Attached are more photos. I have what looks like a very old shackle and two plates off the "old" spring, which was rubber bushed. They all measure 1-9/16. The same as Tom's, including the new "repop" plates on the car now. The fillet on the LH perch base can be seen above the axle pedestal. The left one may be a bit buried, but both perches stand 2.165 inches above the surface of the axle (sorry about the decimals, but we've been in mm for years here, though I still work in decimal inches) measured down from the top grease nipple to the axle. Scaling Hardtimes terrific photos makes his look like 2.2 inches , but camera angles can play tricks.
I cleaned and refitted the perches tightly for the pics. that are without rust marks, and loaded them up in both directions with the car weight and a measuring trammel clamped across them, and they did not move. So I think that's all OK.
So, to get the car going I think I will raise both perches up on tapered spacers until the split pins will just go in nicely. This is about 3/16 inch. I will then take the old, stronger, shorter spring and re-set it cold to about what Columbia suggested (maybe a little less depending on what the refitted perches look like) and then worry about the new spring and what happened to it when I am back on the road, since my car is in a couple of old car shows this weekend and next.
Thanks to you all. Apologies are due because I started my reply at my work 10 hours ago, and with all the interruptions from people that can't seem to do without me, I have cut across some of the replies that came in since. By the way, do some of you guys never sleep? I'm doing this at work today so I don't get too much stick from my wife tonight, when I finally get home!(it's 5.30 pm here now).
Regards
and thanks to all who replied . SAJ in NZ
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Old 02-09-2012, 11:30 PM   #29
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Default Re: roadster front spring problem

photos disappeared along the line! Here they are. forgot to press "upload"
SAJ
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File Type: jpg 2012-02-10 12.16.jpg (71.2 KB, 58 views)
File Type: jpg 2012-02-10 12.18.jpg (64.7 KB, 68 views)
File Type: jpg 2012-02-10 12.19.jpg (71.7 KB, 66 views)
File Type: jpg 2012-02-09 19.07.jpg (65.4 KB, 62 views)
File Type: jpg Resize of 2012-02-09 19.07.50.jpg (66.9 KB, 59 views)
File Type: jpg Rotation of 2012-02-07 17.24.jpg (57.0 KB, 58 views)
File Type: jpg Rotation of 2012-02-07 17.jpg (60.2 KB, 62 views)
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Old 02-09-2012, 11:53 PM   #30
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Default Re: roadster front spring problem

I see you have thought this through and plan to compensate for the perches moving closer together when you raise them the 3/16" you have stated. I gather that the only reason you want to raise them is so that the split pins (cotter pins to us Yanks) will properly engage the nuts. Keeping in mind that those nuts have the taper on them and also are of a "high crown" design are you quite certain that they are not re-faced on the taper, or possibly just too short for your application for whatever reason?
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Old 02-10-2012, 05:27 AM   #31
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Default Re: roadster front spring problem

Fordors, no I am not certain the perch nuts are the right height, but I figured raising the perches will allow the shackles to clear the axle and the amount of inward movement at 7 degrees slope will be tiny (I think so . I have not calculated it).
The cotters were OK where they sit, in fact. But the concensus on this forum seems to be that that the perches may sit too low and I thought I would raise them and see how it looks and then re-set the spring if that looks neccessary too. The whole thing is a bit of a puzzle, because the spring is actually still within the outer end of the spec. (accoring to Les Andrews book - I have not found anything else to go on) for length and arch and I cannot see anything else wrong. But I need to get it on the road for some shows this weekend, and then I will look further at what need s to be done.
There is enough length in the centre bolt to put in another leaf from my old spring as a temporary remedy too, I think. I wonder if this is feasible?
I appreciate your comments
Regards
SAJ
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Old 02-10-2012, 07:55 AM   #32
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Default Re: roadster front spring problem

SAJ, do you suppose it would help if someone had a main leaf that they were sure was original and they measured it? Not for arch and C-C of the eyes, but using a tape measure along the top surface give a C-C dimension.
This would eliminate one variable would it not? Another thing to consider, one can set the arch and have a good C-C, but even then, if the spring rate is too low in effect the car could sit a bit low and the shackles would be affected as yours are.
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Old 02-10-2012, 05:22 PM   #33
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Default Re: roadster front spring problem

SAJ, Qute a puzzel. Do you have access to another axle for a reference? You may want to check the arch of your axle. Judging from the spring wear on the top of the axle spring has or had been been riding hard for a while. Your Perches appear good. Almost too good for the axle wear. They may have been replaced to try to fix the rubbing at some point. There may be some old damage in the axle causing the problem. Can't tell from picture but axle ends from motor side or perch to backing plate appear to pitch down a bit instead of up. If they replaced perches & used lots of heat & Pressure that is the direction they'd bend ( if the axle lost temper). It also would cause the brake shaft not to seat properly and the shock balls to be misaligned in the way they are. Just a thought. Tim
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Old 02-10-2012, 06:48 PM   #34
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Default Re: roadster front spring problem

Does something change because of right hand drive??
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Old 02-10-2012, 08:15 PM   #35
jimvette59
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Default Re: roadster front spring problem

Columbia Ha Ha Ha. Holey S%$T i never noticed that. Thanks.
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Old 02-10-2012, 10:16 PM   #36
columbiA
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Default Re: roadster front spring problem

SAJ How come the RH shackle was installed backwards? The free lengh of the spring should be 30 13/16" to 30 15/16". If you re-arch them,you could make it an inch shorter & it will be OK.
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Old 02-11-2012, 05:09 AM   #37
SAJ
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Default Re: roadster front spring problem

Thanks a bunch guys. I re-arched the spring before all the replies were in. I set the longest spring to plus 1-3/4 inches of arch as per Columbia’s suggestion (on the basis that if a little bit is good, too much is better!), I then reshaped all the other leaves to fit this longest one. But when I bolted it all together, to my surprise the re-arch of the whole assembly was 2-1/4 inches more and the length between eyes 29.1 inches.
I put it in a press and loaded the spring until it was the max length attainable in the car between perches (31-5/8”), and when unloaded the arch had settled to 7”, or 1-5/8 more than before, which is close to Columbia’s suggested 1-1/2 inches.
I put it back in the car at this and refitted the perches as is, with moly on the tapers and copper/lead antiseize on the shank and nuts. They seated well.
The car now sits with plenty of shackle clearance and slightly more on the left than the right.
It is still a mystery what was wrong unless both springs had low spring rates, as Fordors suggested. I believe I was taught years ago that when a spring is reset cold above its yield point the rate actually increases ( for small distortions ). Can a spring expert comment on this?
Maybe I have just compensated for some other unseen problem. The axle outside the perches does seem to “sag” in the photos as Tim suggested, but when looking at the car itself it looks OK.
The shackle was in backwards for one photo because I knew it had to come out again, and every time I went under the car to fit the plate on the back someone called me out again. So I just threw it on from the front temporarily.
You guys are Eagled eyed for sure!
I will fit shocks, cotters, brake rods etc tomorrow and road test it. I hope this crude, cold spring reset is a permanent thing.
Thanks to all who helped and Ryan for providing such a wonderful information resource.
SAJ in NZ
Attached Images
File Type: jpg roadster spring reset before pressing (2).jpg (66.3 KB, 43 views)
File Type: jpg roadster spring unloaded.jpg (80.0 KB, 42 views)
File Type: jpg roadster spring in press.jpg (86.9 KB, 39 views)
File Type: jpg roadster spring reset and pressed (2).jpg (62.5 KB, 42 views)
File Type: jpg roadster spring reset in car LHS.jpg (54.0 KB, 47 views)
File Type: jpg roadster spring reset in car RHS.jpg (61.5 KB, 44 views)
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Old 02-11-2012, 10:03 AM   #38
1931 flamingo
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Default Re: roadster front spring problem

All right!! Thanks for the update.
Paul in CT
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Old 02-11-2012, 11:32 PM   #39
columbiA
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Default Re: roadster front spring problem

SAJ Glad your re-arched spring worked out well. If the axle does have a bend in it,you could check the camber by having the car on a smooth flat floor & standing a carpenters square in line with axle with top of square touching top of tire(tyre)?, then measure distance from bottom of square to bottom edge of tire.If the camber is correct,it should measure 1&13/16".If KP,s are badly worn ,that will affect the camber too.
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Old 02-13-2012, 03:57 AM   #40
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Default Re: roadster front spring problem

Quote:
Originally Posted by columbiA View Post
SAJ Glad your re-arched spring worked out well. If the axle does have a bend in it,you could check the camber by having the car on a smooth flat floor & standing a carpenters square in line with axle with top of square touching top of tire(tyre)?, then measure distance from bottom of square to bottom edge of tire.If the camber is correct,it should measure 1&13/16".If KP,s are badly worn ,that will affect the camber too.
This is interesting. Both wheels seem to have less than 1 degree positive camber. Neither my hoist platform nor the floor were flat enough for my carpenter's square to be used accurately, though both are level over a larger distance. The carpenters square touched both tyres top and bottom, more or less. Nothing like the gap Columbia suggests above. An adjustable engineer's level held against a spirit level (as a straight edge) on each tyre showed a bit less than 1 degree tilt on both. Looking straight on at the car, I would swear this cannot be so- camber looks quite a bit more than this. But the photo showing the hoist post in the background shows tyre and post are about parallel. The car was level overall ( large spirit level across the chassis side to side).
The car steers well, up to 60+ mph, and is very stable even tho I have over 2 inches play in my 7 tooth box. I have not been much faster. Tyres show no unusual wear. Suspension over bumps is now much improved.
Less camber would need an axle bent upwards at the ends, moving the perch eyes inwards and making less room for the shackles to swing, as I had.
I am aware camber should be 3-1/2 degrees each side so the kingpin axle bore ( at 7 deg.), spindle bores (at 10-1/2 deg.) and tyre centre line intersect at the contact patch for correct steering geometry.
So I guess I will keep an eye on tyre wear and maybe look out for another good axle. Or maybe remove it and put it in my press and adjust as per Kevin in NJ's web page when I get time.
By the way kingpins are a tight fit with no play, and a tiny bit of play in the front wheel bearings- the merest trace of rock, which is how I keep them adjusted.
On the spring reset I did, I recalled afterwards that a hot initial setting, then cold plastic deformation back beyond the point of max. load is called "scragging" to give an increase in spring constant by manipulation of the built-in stresses in the tension and compression surfaces of the leaves. What I did was sort of a "scrag" (lovely word) in concept, but a bit unorthodox. I has done the trick in the short term at least. But I do seem simply to have compensated for another problem - a bent axle, as several suggested.
Again thanks to all, many of whom I did not acknowledge. All the replies were helpful.
SAJ in NZ
Attached Images
File Type: jpg wheel shown parrallel to hoist.jpg (45.7 KB, 26 views)
File Type: jpg spirit level on LH tyre.jpg (58.2 KB, 29 views)
File Type: jpg spirit level on LH tyre (2).jpg (53.8 KB, 27 views)
File Type: jpg spirit level on RH tyre.jpg (46.6 KB, 26 views)

Last edited by SAJ; 02-13-2012 at 10:05 PM. Reason: spelling
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Old 02-13-2012, 05:25 AM   #41
SAJ
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Default Re: roadster front spring problem

I just did a search for "camber" and found the following from Marco Tahtaras:
Re: Alignment Specs

[Follow Ups] [Post Followup] [Fordbarn Model A Discussion Forum] Posted by Marco Tahtaras from c-24-4-43-195.hsd1.ca.comcast.net (24.4.43.195) on Saturday, July 12, 2008 at 1:44AM :
In Reply to: Alignment Specs posted by Don/WW from 75-139-191-109.dhcp.wa.charter.com (75.139.191.109) on Saturday, July 12, 2008 at 0:53AM :



["Obviously the original camber was fixed. I'd have to dig through some notes to be sure of my calculations but believe the original camber was fixed at 1.5°(actually 1.475°). In the late '30s when Ford had alignment equipment for the dealers they specified a range of .25°- 2° with max variation of .25° per side.



Reduced camber (common) adds to instability and wandering chacteristics as well as increasing the odds of low speed front end shimmy."] UNQUOTE.

Les Andrews says 3-1/2 degrees per side. My Camber is close to Marco's figure, so I feel a bit happier, though I still cannot relate that to the 1-13/16' figure, which seems miles more than I have (about 0.2" per side I think).
Regards
SAJ in NZ
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Old 02-14-2012, 12:34 AM   #42
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Default Re: roadster front spring problem

SAJ you are right,the 1 13/16" figure from my book does seem excesive.I checked both my A,s & the measurement was 1/2 that per side.Perhaps the previous measurement was the total of the two sides.Both cars steer perfect up to 60.I usually dont go over 60 even in OD,as I like to keep the RPM,s down for long engine life.
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Old 02-14-2012, 02:15 AM   #43
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Default Re: roadster front spring problem

Thanks ColumbiA. My Les Andrews book says 1-13/16 each side. I have seen this elsewhere too, plus 3-1/2 degrees each side. I think I will leave mine for the moment, and work on other problems, since it is riding nicely now. Thanks again. Marvellous resource!
Stuart Jordan aka SAJ
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Old 02-14-2012, 12:01 PM   #44
Bob C
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Default Re: roadster front spring problem

I looked at the camber diagram in the Service Bulletins and I think 1 13/16
is the total for both wheels.

Bob
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