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StudeRich
08-08-2006, 08:08 PM
Thanks much, 55prez and Alan for all your help. We borrowed a new Chuck Collins repro spreader tool from another SDC member and replaced the upper and lower outer pins on my '59 Lark VIII, actually they are going on the '59, but they are '61 Lark King Pin/A arm assembies that were already rebushed on the inner ends. I am aware that I will need to align it with close to 0 degrees instead of -2 1/2 caster with the late style king pins.
But here is the problem...the spreader holds the top of the A arms, but under what must be 250-300 ft.LBS of torque it takes to really force those outer pin caps to thread all the way flush with the A arms, the bottom pinches in .030 to .100 thou, when it should hold .015! The repair manual shows the spreader mounted on top of arm, so we mounted it there and spread it to 2.750 + .015 and wrenched away on those caps, a little at a time on each end. They are unbelivably hard to drive in. The result was that there may not be enough room to move the K/P to read 0 degrees to -1 1/4 to align it. I can see those grease seals being really flatened if it will even go that far. It would be way worse on a pre '61 where it requires up to -2 1/2 degrees caster! Has everyone who does this right had to fight this hard to do it? exhausted and dissapointed - Rich.
PS almost makes you want to put one O-those cheeseball pinto front ends in! [xx(]
quote:
--------------------------------------------------------------------------------
Originally posted by Alan

2.750" or 2 3/4"

added by Rich:(this is the correct spread of the outer end of the '51-'66 upper & lower "A" arms.)

--------------------------------------------------------------------------------

StudeRich
Studebakers Northwest
Ferndale, WA

wagone
08-08-2006, 10:37 PM
Hey StudeRich, I've been reading these threads with interest and yesterday measured my Avanti outer top a-arms. One of mine is 2.650" and the other 2.690" (both plus or minus .003" or .004"). So I'm very interested as to what others have to say about this. On the one which is 2.690" I installed a new pin and bushings about two years ago and until now I didn't know that the measurement was supposed to be 2.750"....so I just tried (without the J2044 tool, or whatever the number is) to hold the plus .015" measurement. So the question I have is how to bend the "ears" on the end of the a-arm and can they be bent that much without damage (.050 to .100")? This appears to be a VERY critical process in doing front end work and I would love to see a poll of Stude owners as to the measurement on their cars. How many have been screwed up by sloppy mechanics at some point in the past? The lower is also to be 2.750" but it appears nigh on to impossible to measure the lower with the suspension on the car. Comments, guys, please!

wagone and the R2 Avanti

64V-K7
08-09-2006, 08:17 AM
The important thing is that, in operation, the pin and cap bushings do not turn in the ear of the control arm, as one unit. The force required to achieve the specification torque has to vary. New arm = x, old arm = y ( if you follow the original threads), old arm =Y+x ( if you're cross threading the old install, etc

The spreader tool creates an artificial barrier to torque the cap bushings to. It combines the inner ramp of the pin threads and the resisitance of the outer bushing, in the ear, to satisfy the torque requirement. Once both caps are tight, the spreader is released and resulting movement frees the ramp of the inner pin threads from the torque (and bushing threads). This is what allows the pin to turn, inside the bushings.

If the spreader isn't used, the cap bushings are then torqued to the pins. In this case, the up/down motion of the suspension can only work if the rotation of the pin is translated thru the bushings to the arm. This would force the cap bushing to turn inside the ear and shortly wear it out.

Alan
08-09-2006, 01:06 PM
You tell em Prez, When I measured the 2.750 I have 2 NOS still in Stude boxes arms and 4 used ones. they all measured 2.747-2.753". 2.750" plus or minus .003" now over the years things could have been crunched, banged or maulled to change the specs. On one of the used lower arms I have it is almost 1" tighter on the inside where the rubber bushings are where it appears that someone used a press to get the bushings in or out and didn't use the tool to keep them spread.

StudeRich
08-09-2006, 01:18 PM
WOW thanks a lot 55Prez; that's a little deep, but I think I get it.[^] It's all about transfering the stress to the arm and not between the bushing caps and the shaft. I have aligned these myself and remember (it's been awhile) that it was not hard at all to turn the shaft (pin) with the small allen wrench.
Maybe the dimension at the end of A arm and bottom are not that critical, and they will be fine at .030 and .100 under the 2.750. :)
Or, I could back the bushings out, risking galling the arms too much and making the fit looser when I force them back in with a little more spread so they spring in closer to 2.750 when done. :(This probably would not ruin the arms THIS time, but it would be the last time!


quote:Originally posted by 55Prez

The important thing is that, in operation, the pin and cap bushings do not turn in the ear of the control arm, as one unit.

StudeRich
Studebakers Northwest
Ferndale, WA

wagone
08-09-2006, 01:33 PM
StudeRich, I'm a little confused by your most recent post. At first you appear to say that your arms are OVER the 2.750" (and mine are UNDER)--but then later in your last post you seem to be saying that were you to take them apart again you might be able to get "them to spring in closer to 2.750"." I'm wondering how they might get spread apart to more than 2 3/4"? When turned with an allen wrench mine rotate easily enough, but I might try and find four arms close to 2.750" and redo the whole thing with all new parts (at least the parts that can still be purchased new). On closer read your statements do coorelate, I'm just wondering how they would be spread apart--I can see closing when the bushes are pulled in during installation if J-2044 is not used.

wagone

StudeRich
08-09-2006, 03:16 PM
Wagone, you are right I changed it to say "UNDER".

Thanks, Rich

StudeRich
Studebakers Northwest
Ferndale, WA

sbca96
08-09-2006, 04:57 PM
Anyone have a picture of where they are measuring at?

Tom

StudeRich
08-09-2006, 05:12 PM
Tom; the shop manual shows it being measured on the end of the arm at just above the pin on the uppers and at the centerline of the pin on the lowers. They measure the outside, but we have been going from the inside measurement that Alan gave us, which is very consistent with everyone's NOS arms. Too bad the manual does not state the actual dimension. I guess they knew it would vary a bit, so they went with something like: "spread it .015 from where it was".

Update:Added 3:56PM PDT I tried measuring the OUTSIDE of my upper A arms like the manual and came up with 3.475 and 3.490 these are the original "build", I have not removed anything since we rebuilt them yesterday. I think they are supposed to be 3.500 but no way to be sure, since there are no specs. That does not sound so bad though
-.010 and -.025 maybe I should just "GO FOR IT" and throw it together like the alignment/front end shops probably did, I gotta be closer than them if they never used the spreader!!!:D[^][:0]
Rich.

quote:Originally posted by sbca96

Anyone have a picture of where they are measuring at?
Tom

StudeRich
Studebakers Northwest
Ferndale, WA

gordr
08-09-2006, 11:12 PM
For what it's worth, I have changed the outer bushings before without a spreader tool (didn't have one, do now). I have never experienced the binding problem, where the bushing cap seats on the pin. But I was always VERY careful to try to make the new bushing line up with the "threads" in the arm itself. If that is done, the bushing will usually screw in quite easily.

I have seen them become so loose in the arm that they have been tacked in by a little weld, either by myself or a previous worker. Not a recommended procedure, but it can get you by until a proper front end rebuild can be done. Less call for that sort of thing now, but when Studes were being used as daily drivers by relatively poor people...

The shop manual assumes that the work is being done in a well-equppied dealer shop with an ample supply of new parts and all the special tools. It tells you the "right" way to do things, but it does not tell you what you can get by with when resources are scarce. (Nor should we expect it to.)

Gord Richmond, within Weasel range of the Alberta Badlands

wagone
08-10-2006, 12:35 AM
It is now past 11 pm here in the midwest. Tomorrow I intend to measure the outside of my a-arms as StudeRich has done and report back on this thread with my measurements. I'm hoping that we can generate some discussion on what minimum dimensions might be encountered and not expect to have a problem. As has been stated earlier, neither StudeRich nor I have any frictional or binding problem with the pins when turning them with the allen wrench as one would when doing the caster/camber alignment. Is that a fair assessment as to whether or not a problem can be expected between the male and female threads of the pins and bushings? It would appear that being able to turn the pin without binding would indicate that alignment (pin and bush alignment--not suspension alignment)is pretty good--assuming no appreciable wear of the threads that is. As stated earlier I replaced one of my outer upper pin and bushings about two years ago and that a-arm measures 2.690" (1/16" approximately under spec)--replaced with NEW parts. I have no binding when turning that pin with an allen wrench. The other side (left in this case) is 2.650" and the pin doesn't bind in that one either but there may be a fair amount of wear in that pin and or bushes. I replaced the right upper pin and bushes because my suspension had (still has) a knock somewhere and the washer type "gaskets" at that location were SHOT--funny thing is that pin and bushes (the threads) do NOT seem unduly worn. Anyway, I'd like comments (and perhaps StudeRich would also--after all this is his "thread") on any of the above. Thanks.

wagone and the R2 Avanti

Mike
08-10-2006, 09:19 AM
Comments:
I have a couple of used pins from a '57 Hawk. I think they are original Stude parts.
The grooves on the outside of the caps are definitely spiral threads; not just parallel ridges.
I counted the number of threads on the outside of the caps, and on the pin. There is the same number of threads per inch on both. I had half expected to find divergent threads; but that is not the case.
The cap has to enter the "A" frame at the same rate as it screws onto the pin. I guess the spreading tool is just to keep the "A" frame from deflecting; as the threads on the pin pull the cap into place.
Is it possible to make the joint bind, and maybe not take grease, by tightening the caps so they pull against each other, on the pin. The .015" preload from the spreader would make that worse. Backing off one cap may help.
Mike M.

wagone
08-10-2006, 01:52 PM
Mike M. But backing off one cap or the other (or both I suppose) would make it (them) short on torque, wouldn't it? We (I, at least) need an expert. AND who do you trust as an "expert" after 40 plus years?

wagone

studegary
08-10-2006, 04:10 PM
quote:Originally posted by wagone

Mike M. But backing off one cap or the other (or both I suppose) would make it (them) short on torque, wouldn't it? We (I, at least) need an expert. AND who do you trust as an "expert" after 40 plus years?

wagone


40 plus years ago, I was working full time in a garage that actually fixed things like front ends and rebuilt engines, but my memory doesn't lend anything to add to this thread.

Gary L.
Wappinger, NY
1954 Commander Starliner (restomod)
1959 DeLuxe pickup (restomod)

Alan
08-10-2006, 04:25 PM
Rich, I measured the outsides of the 6 I have around here the measurements were all over the place, between 3.480-3.525" the cover of the arm that the pads are spot welded to tapers and at the end where you would put the spreader is the most bent out of shape. Since there is no hard and fast diminsions in the Stude shop manuals I would say you are trying to make a mountain out of an a-arm.

StudeRich
08-10-2006, 04:42 PM
The spreader goes on the TOP of the arm on the outboard end of the "C" shaped cutout on top, not on the bushing support area!

StudeRich
Studebakers Northwest
Ferndale, WA

wagone
08-10-2006, 05:13 PM
Alan, .045 might be a "mole hill", but is .100" also a mole hill (pardon me, a-arm)? Where do you suppose we draw the line? Any significant (and no I'm not trying to suggest what is significant and what isn't) bending of these "ears" is going to cause an angular degree of nonparallelism between the bushes and the pin which will cause binding and or excessive wear of the threads--or am I wrong. But what is significant? Surely the factory spreading of .015" to facilitate PROPER installation is not much compared to .045" or .100". GETTING THESE PINS INSTALLED CORRECTLY SEEMS A SIGNIFICANT ISSUE TO PROPER FUNCTIONING OF THE SUSPENSION. And again, I'm not trying to sound like a smart a**--just looking for answers. Please understand.

wagone

Alan
08-10-2006, 09:03 PM
wagone, What I was trying to say is as long as everything is kept parrallel it probably dosn't matter much how wide it is between the pads you cannot get the caster specs. you would like anyway. The way our cars get treated it is surprising that after 40 or 50 years they aren't worse than they are. But if he is worried that mine is bigger than his then there are always spam mails for that.

wagone
08-10-2006, 09:26 PM
Alan (and others), I've always assumed (and we all know what problems that can cause) that the earlier cars which used a larger negative caster had that built into the front end by relocation of attachment points for the upper or lower a-arms. What I mean is that I'd thought that it wasn't expected to get all that range of adjustment through the years in the pins. The MM washer type gaskets would be squeezed to nothingness if nothing else. Yes, as long as the parallelism is maintained I don't think it matters but if the ears are bent to a distance significantly less than 2 3/4 inches I don't see how the centerlines of the pins and bushes can possible coincide--hence a problem with wear or high resistance (frictional). It certainly seems a serious issue to me--if for no other reason than that those old king pin suspensions need (or seem to need) all the help they can get. I hope StudeRich and others stay with this so we can learn something and have StudeRich explain what he finally ends up with. As has been said, what happens if the threads bind is that the bushings are going to turn in the ears--not a good thing by any stretch of the imagination!

wagone and the R2 Avanti

StudeRich
08-11-2006, 01:26 AM
Update Friday Aug.11, 2006
Thanks for your help and support Wagone and all, yes I will finish this '59 Lark VIII Regal 4dr. It's my driver and a great little car!:) It will go on the road with A arms a few thousands too narrow and I will be watching those bushings and also see if the upper pins remain free to turn. It will be interesting to see what the alignment shop says about it. I have over $200.00 worth of parts in just those 4 outer pins, so I am not quiting now! I replaced the center support (bellcrank) bearings and used the modern "O" ring seals on it and the king pin (did not even see any remains of the old corks). Also replaced the king pin thrust bearings. Everything else on the K/P's looked great. This started out as Just a complete brake job and kinda escalated to a lot more. Good luck with your Studes.:)

StudeRich
Studebakers Northwest
Ferndale, WA

Roscomacaw
08-11-2006, 03:01 PM
Good, in-depth thread here. I confess, that like gordon, I've replaced these bushings without the spreader. Truth is, it's been a few years since I dealt with a front end rebuild. Maybe 5 or so -although I did redo a Champ truck front axle not too long ago.

Anyway, I'd like to add my concurrance to something that gord said - and it's something that we see evidence of here on a regular basis.
The shop manuals were written with the assumption that the people using them were EXPERIENCED mechanics. Not to say that there isn't lots of info for us less experienced types, but oft times here someone will say, "Geez, the shop manual doesn't describe that (or illustrate that) very well!"
What was not written into the books were basics like torque tables for standard bolt and nut sizes, what sorta wrench to use where, or many other little "tricks" that some veteran wrench turners just do without thinking. Mechanic wanna-bees (back then) usually got their start washing parts, changing tires & oil and working their way up from there. They learned the craft of mechanicing thru their own skinned kuckles while at the elbow of an old timer. Maybe they took auto shop in high school or got some training thru joining the service. Thing is, by the time they leafed thru the pages of a Studebaker shop manual in earnest, they had some ability to read what WASN'T written as well as what was.

Anyway, if you've gotten your shop manuals and they've left you cold, that's why Gordon & Rich & Dwain & others, including myself, are here.;) If we can help you to interpret the manuals by adding tips and insights that aren't spelled out, then we're gonna see more pretty Studebakers show up at the meets and at intersections everywhere.;)

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

wagone
08-11-2006, 04:25 PM
I've just now come in from my garage after having taken some measurements on my Avanti's front suspension and in particular upper a-arm measurements. Initially a couple of you gave a measurement on a known good or NOS a-arm of 2.750" as the inside of the "ear" portion of the arm--and I believe this measurement is taken from the inside surfaces of the "insert" into which cap bushing is threaded. My a-arms measure 2.650" and 2.690" and I've assumed (there's that durn word again), quite naturally I think, that this reduction implies that the ears are bent inwards--not a good thing as far as parallelism is concerned. However, after the measurements I've just taken I'm not so sure. The outside of both my upper a-arms at the outer edge of the "ears' measure 3.440" (within about plus or minus .005") and if I go inwards towards the inner portion of the a-arm two full inches to the point where the arms start to widen out or curve out to ultimately end in the inner attachment points this 3.440 measurement only increases .015" on one a-arm and about .025" on the other arm--not what I'd expect to find if the "ears" were bent a significant amount. My trig tables tell me that .020" in 2" inches is an angle of a little over 2 degrees--not very significant in the manufacturing process and maybe not enough to cause a binding of the threads. And the only way I can account for the fact that StudeRich and I both have an arm that is under the 2 3/4" by .100" (and the cause not be bent "ears--and the one of mine measuring 2.650" has less of a "taper" than the one measuring 2.690") is in manufacturing at South Bend. Go figure, but I've confirmed to the best of my ability that my ears have far less "taper" and hence nonparallelism than I would have thought. Jon Myer gives a very good explanation (IMHO) of why the J-2044 tool is used in this month's Turning Wheels Cooperator section. Thanks to Jon. Anyone care to shed more light on this topic? Is the horse dead--probably not as this is (again, in MHO) a fairly important issue.

Addendum: I've been noticing the number of entries on to this post and there appears to still be interest. So.........with egg on my face I have to admit to an error in my math (see what happens when age enters and youth disappears) the angle I mention above is actually less than one degree (and significantly less) from being parallel. And I cannot satisfactorily explain why some arms measure 2.750" and others as low as 2.650" (and not be bent).

wagone and the R2 Avanti

Alan
08-13-2006, 01:39 PM
Production tollerances, those doughnuts spot welded inside the stamped arms. When I put a dial bore gauge in there some of those spot welds are .040"-.050" deep it is hard to do precision work with such rough parts to start with.

prager
08-14-2006, 07:32 AM
Hello all, I have re done the front end of my 62 Lark and ran into the spreader problem myself...No spreader, I went on without. I do not remember the caps going in very hard at all.. But it seems like one side went in more than the other, and smashed against the rubber gasket pretty good. I have not driven the car at all, as this was part of the resto job. Should I back all of the caps out and spread to spec and re tighten, or is it too late? Thanks!!

sbca96
08-14-2006, 12:16 PM
prager,

Unless you cross threaded something, I dont think its EVER "too late"
to do it right. Sounds like an important issue for the long term.

Tom

robtc
08-14-2006, 01:26 PM
Since I will soon be working on the front end, I will add another question.

How smashed against the rubber gasket should the caps be?

StudeRich
08-16-2006, 02:48 AM
I can only tell you how my '59 Lark outer pins went in with the spreader(which is detailed in this and my other post) As to the distance between the new grease seals & the bushing (cap). We turned each cap a little at a time trying to center the king pin in the A arm. When finished the arms were only compressed .040 to .060 under the 2.750 so the seals have about a .060 gap between them and the bushings. They will need this room and maybe more, to be aligned (castor set)! :D
Rich.


quote:Originally posted by robtc

Since I will soon be working on the front end, I will add another question.

How smashed against the rubber gasket should the caps be?


StudeRich
Studebakers Northwest
Ferndale, WA

prager
08-17-2006, 01:45 PM
So is it possible that some may touch the seals or come close, and others may slightly squish the seal?

StudeDave57
08-17-2006, 10:10 PM
Mike, you been working on Dad's car again? [:0] ;) :D :) [^]

StudeDave [8D]
V/P San Diego County SDC
San Diego, Ca

'54 Commander 4dr
'57 Parkview (it's a 2dr wagon...)
'57 Commander 2dr
'57 Champion 2dr
'58 Packard sedan
'65 Cruiser

bondobilly
08-17-2006, 10:58 PM
quote:Originally posted by StudeRich

I can only tell you how my '59 Lark outer pins went in with the spreader(which is detailed in this and my other post)

quote:Originally posted by robtc

Since I will soon be working on the front end, I will add another question.

How smashed against the rubber gasket should the caps be?


I am screwed, back in 1986, I just hit each end of the A arms with a heavy hammer, One hit on all four points. Now 20 years later I find out I did it wrong.

BG

http://bondobilly.com./1sdc.jpg Proud owner of the Hawk from Hell

StudeRich
08-21-2006, 11:04 PM
Prager; YES it is, but only in service or after alignment, usually one squashed & one not. On installation they would be centered having no tight contact with king pin. I would bet that your inside measurement on the end of the A arms is less than 2.750 after assembly without the spreader! :(
Also note that others, and YES including myself have years ago installed these WRONG:( The first car I did, has been driven all of 2500 miles in 40 years so who knows if it will fail!:D


quote:Originally posted by prager

So is it possible that some may touch the seals or come close, and others may slightly squish the seal?


StudeRich
Studebakers Northwest
Ferndale, WA