|
Sponsored Links (Register now to hide all advertisements) |
|
|
Thread Tools | Display Modes |
02-09-2012, 10:54 AM | #21 |
Senior Member
Join Date: Jun 2010
Location: Perry OH
Posts: 1,327
|
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
|
02-09-2012, 04:17 PM | #22 | |
Senior Member
Join Date: May 2010
Location: South California
Posts: 6,188
|
Re: roadster front spring problem
Quote:
fROM 'someone' This rebuilt frontend has about 1200mi on it to date. '30 roadster. Last edited by hardtimes; 02-09-2012 at 04:53 PM. Reason: add... |
|
Sponsored Links (Register now to hide all advertisements) |
|
02-09-2012, 05:00 PM | #23 |
Senior Member
Join Date: May 2010
Location: South California
Posts: 6,188
|
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! |
02-09-2012, 06:36 PM | #24 |
Senior Member
Join Date: May 2010
Location: Mpls, MN
Posts: 27,582
|
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.
|
02-09-2012, 07:39 PM | #25 |
Senior Member
Join Date: May 2010
Location: Orland Park,IL
Posts: 1,400
|
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. |
02-09-2012, 07:47 PM | #26 |
Senior Member
Join Date: May 2010
Location: South California
Posts: 6,188
|
Re: roadster front spring problem
Sponsored Links (Register now to hide all advertisements)
|
02-09-2012, 09:33 PM | #27 |
Senior Member
Join Date: Nov 2011
Location: B.C. Canada
Posts: 1,746
|
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.
|
02-09-2012, 11:27 PM | #28 |
Senior Member
Join Date: Jul 2010
Location: Auckland, New Zealand
Posts: 513
|
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 |
02-09-2012, 11:30 PM | #29 |
Senior Member
Join Date: Jul 2010
Location: Auckland, New Zealand
Posts: 513
|
Re: roadster front spring problem
photos disappeared along the line! Here they are. forgot to press "upload"
SAJ |
02-09-2012, 11:53 PM | #30 |
Senior Member
Join Date: May 2010
Location: Orland Park,IL
Posts: 1,400
|
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?
|
02-10-2012, 05:27 AM | #31 |
Senior Member
Join Date: Jul 2010
Location: Auckland, New Zealand
Posts: 513
|
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 |
02-10-2012, 07:55 AM | #32 |
Senior Member
Join Date: May 2010
Location: Orland Park,IL
Posts: 1,400
|
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. |
02-10-2012, 05:22 PM | #33 |
Senior Member
Join Date: Oct 2011
Location: Southern Maine
Posts: 162
|
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
|
02-10-2012, 06:48 PM | #34 |
Senior Member
Join Date: May 2010
Location: Idaho
Posts: 150
|
Re: roadster front spring problem
Does something change because of right hand drive??
|
02-10-2012, 08:15 PM | #35 |
Senior Member
Join Date: Jun 2010
Location: Perry OH
Posts: 1,327
|
Re: roadster front spring problem
Columbia Ha Ha Ha. Holey S%$T i never noticed that. Thanks.
|
02-10-2012, 10:16 PM | #36 |
Senior Member
Join Date: Nov 2011
Location: B.C. Canada
Posts: 1,746
|
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.
|
02-11-2012, 05:09 AM | #37 |
Senior Member
Join Date: Jul 2010
Location: Auckland, New Zealand
Posts: 513
|
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 |
02-11-2012, 10:03 AM | #38 |
Senior Member
Join Date: May 2010
Location: new britain,ct 06052
Posts: 9,389
|
Re: roadster front spring problem
All right!! Thanks for the update.
Paul in CT |
02-11-2012, 11:32 PM | #39 |
Senior Member
Join Date: Nov 2011
Location: B.C. Canada
Posts: 1,746
|
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.
|
02-13-2012, 03:57 AM | #40 | |
Senior Member
Join Date: Jul 2010
Location: Auckland, New Zealand
Posts: 513
|
Re: roadster front spring problem
Quote:
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 Last edited by SAJ; 02-13-2012 at 10:05 PM. Reason: spelling |
|
Thread Tools | |
Display Modes | |
|
|
Sponsored Links (Register now to hide all advertisements) |
|