Front axle preparation

jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Front axle preparation

Post by jstoezel »

Hi,

I am preparing the front axle of my FV and I have a few questions.

I've disassembled the brake plates and noticed the brake shoe adjusting screws have a bevelled profile (not flat).
http://img510.imageshack.us/img510/6121/dsc0207y.jpg
However, the brake shoes have a flat profile (where the adjusting screws seat). My understanding is that they are 2 styles of adjusting screws, flat and bevelled. As well they are 2 matching styles of brake shoes. Is this true? What's the difference between the 2 setups? I have to get new shoes anyways, I could go either with the bevelled type, or go with the flat type (and change the adjusting screws). What setup is recommended?
By the way, the star nut spring is broken on this picture.

I am confused when it comes to checking whether or not parts have been modified to add negative camber to the front wheels. I took pictures of the spindles assembly, could somebody tell me if these have been modified, and how to know if they got modified?
http://img510.imageshack.us/i/dsc0208r.jpg/
http://img713.imageshack.us/i/dsc0210b.jpg/
What I currently believe is that if these spindles had been modified, the washers in this pictures should be off-centered. They are centered, which makes me think this is a stock setup. Could somebody confirm?
http://img256.imageshack.us/i/dsc0211a.jpg/

Last question for now:
The end profile of the turkey legs is different, on the left and on the right side.
The right side legs have a square profile:
http://img710.imageshack.us/i/dsc0213lx.jpg/
The left side legs have a round profile:
http://img689.imageshack.us/i/dsc0214e.jpg/
Is this expected? Or do I have 2 styles of turkey legs on each side?
Last edited by jstoezel on January 22nd, 2011, 3:33 pm, edited 6 times in total.
Jean-Sebastien Stoezel
WCMA FV #0
tiagosantos
Posts: 389
Joined: June 20th, 2010, 12:10 am

Re: Front axle preparation

Post by tiagosantos »

Yup, there are two styles, flat and angled. If I remember right, it has been mentioned that you can grind the brake shoe to match the angle of the adjuster in a pinch, but they do sell angled shoes. The FV suppliers will know all about this and sell you whichever type you need :)
Dietmar
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Re: Front axle preparation

Post by Dietmar »

You have pretty much answered your own questions with the correct answers:

There are two styles of adjusters and the shoes need to fit the style you are using. You can change adjusters or shoes. Since you are getting new shoes, just get the ones that fit your adjusters. Save a few $$$$$$

I would not grind the ends of the shoes however!

On the link pins- I would suggest cleaning them up a bit and then posting new pics. Hard to tell with the grease. Once cleaned, look at the bushings and see if they are offset- fatter to one side of the hole than the other. From the looks of the spindle standing up , it APPEARS the link pins are at an angle- suggesting offset bushings, but the bushings themselves could be worn and give the appearance of being at an angle.

On the arms- yes, you have the older and newer arms. In the stock set up, this would require different shim stacks ( the groove held a small "O" ring seal). You could use either arms the way they are as you will probably be using offset bushngs and then playing with the shim stack.
The stock shims will not work well with offset bushings ( as you already mentioned the shims should not be centered on the holder with offset bushings). The shims' od. are turned down a bit to allow them to fit in the carrier.

Hope this helps.
Feel free to call if you have any other questions.

Dietmar
http://www.quixoteracing.com
619 561 7774
jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Re: Front axle preparation

Post by jstoezel »

Thanks for the reply.

As soon as I get home I'll clean up the bushings and post pictures. I'm pretty certain the bushings' holes are centered. You might be right, the bushings are probably worn. I was able to move the link pin around on an angle inside the assembly.


Dietmar wrote:You have pretty much answered your own questions with the correct answers:

There are two styles of adjusters and the shoes need to fit the style you are using. You can change adjusters or shoes. Since you are getting new shoes, just get the ones that fit your adjusters. Save a few $$$$$$

I would not grind the ends of the shoes however!

On the link pins- I would suggest cleaning them up a bit and then posting new pics. Hard to tell with the grease. Once cleaned, look at the bushings and see if they are offset- fatter to one side of the hole than the other. From the looks of the spindle standing up , it APPEARS the link pins are at an angle- suggesting offset bushings, but the bushings themselves could be worn and give the appearance of being at an angle.

On the arms- yes, you have the older and newer arms. In the stock set up, this would require different shim stacks ( the groove held a small "O" ring seal). You could use either arms the way they are as you will probably be using offset bushngs and then playing with the shim stack.
The stock shims will not work well with offset bushings ( as you already mentioned the shims should not be centered on the holder with offset bushings). The shims' od. are turned down a bit to allow them to fit in the carrier.

Hope this helps.
Feel free to call if you have any other questions.

Dietmar
http://www.quixoteracing.com
619 561 7774
Jean-Sebastien Stoezel
WCMA FV #0
jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Re: Front axle preparation

Post by jstoezel »

I checked and there is no need for me to add more pictures. The offset bushing are centered. Looks like I have to get these fixed. Can I just buy the bushings, or do I have to send the spindle carriers somewhere to get them modified?

In a previous picture it appears that the star nut spring is broken. I have a replacement for it, though how do you typically replace these? They seem to be force fitted and they seem to require a bit of grinding to get them out. Once out, how do you recommend installing the new spring? CIP is alluding to some welding that may be required...Can spring metal be welded to the back plate?

For my own information, what is the difference between the beveled adjusting screws and the flat ones? Which one is newer, why did they go with different designs?

Thanks,
Jean

Dietmar wrote:You have pretty much answered your own questions with the correct answers:

There are two styles of adjusters and the shoes need to fit the style you are using. You can change adjusters or shoes. Since you are getting new shoes, just get the ones that fit your adjusters. Save a few $$$$$$

I would not grind the ends of the shoes however!

On the link pins- I would suggest cleaning them up a bit and then posting new pics. Hard to tell with the grease. Once cleaned, look at the bushings and see if they are offset- fatter to one side of the hole than the other. From the looks of the spindle standing up , it APPEARS the link pins are at an angle- suggesting offset bushings, but the bushings themselves could be worn and give the appearance of being at an angle.

On the arms- yes, you have the older and newer arms. In the stock set up, this would require different shim stacks ( the groove held a small "O" ring seal). You could use either arms the way they are as you will probably be using offset bushngs and then playing with the shim stack.
The stock shims will not work well with offset bushings ( as you already mentioned the shims should not be centered on the holder with offset bushings). The shims' od. are turned down a bit to allow them to fit in the carrier.

Hope this helps.
Feel free to call if you have any other questions.

Dietmar
http://www.quixoteracing.com
619 561 7774
Jean-Sebastien Stoezel
WCMA FV #0
BobShedd
Posts: 57
Joined: July 16th, 2006, 10:34 am

Re: Front axle preparation

Post by BobShedd »

If you are not sure about pressing the offset bushings in, I would suggest you send them to Dietmar or SR or your perfered F/Vee shop. You probably want to have them check the king pins at the same time to make sure all is in perfect condition ( not sloppy loose ) when you put it all back together. My $0.02
Bob
hardingfv32-1
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Re: Front axle preparation

Post by hardingfv32-1 »

Too much heat is going to kill the star nut spring. You might be able to fit a small piece of steel over it (about .5" square?) and silicon braze that using a TIG. The best way is to drill and tap. Then use a screw to mount the star nut spring.

Brian
Dietmar
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Re: Front axle preparation

Post by Dietmar »

Jean:

You can buy the bushings and install them yourself, however, once installed, you will notice that the bushing sticks out of the carrier at one spot and is recessed in another. These surfaces must be flush. You can do this with a special tool- or use a grinder with a PSA disc. Takes time but will work. You might also have to radius the carrier itself depending on the od. of the link pin head. You will also have to find a source for shims ( modified ones at that).

As Bob suggested, anyone listed on this site would be able to help with installation. I am aware of the Canada/US issue. I do not know what is available in "your neck of the woods" but now would be a good time to have the entire assembly checked- king pins, crack check, and to be sure the spindle is straight. Cheap insurance.

As for adjusters- can only guess as to why VW made the change. As with most of their changes, they were in anticipation of future model changes. The straights were used from 58 to 64 and the angled from 65 to 78.

Hope this helps
Dietmar
http://www.quixoteracing.com

(sent this earlier - pressed SUBMIT and it went to cyberspace so if this is a duplicate, my apologies)
jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Re: Front axle preparation

Post by jstoezel »

Taping sounds like a good idea, thanks for the suggestion
hardingfv32-1 wrote:Too much heat is going to kill the star nut spring. You might be able to fit a small piece of steel over it (about .5" square?) and silicon braze that using a TIG. The best way is to drill and tap. Then use a screw to mount the star nut spring.

Brian
Jean-Sebastien Stoezel
WCMA FV #0
jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Re: Front axle preparation

Post by jstoezel »

Well a couple of weeks ago I was chatting with Bill Vallis from VMS. He's located in Canada, and I believe he is the closest shop (3500km still away). At least he is the only Canadian FV shop I know off... Looks like I will be shipping the spindle assemblies to Ontario.

Thank for the good advices Dietmar, too bad you're on the other side of the continent.

Dietmar wrote:Jean:

You can buy the bushings and install them yourself, however, once installed, you will notice that the bushing sticks out of the carrier at one spot and is recessed in another. These surfaces must be flush. You can do this with a special tool- or use a grinder with a PSA disc. Takes time but will work. You might also have to radius the carrier itself depending on the od. of the link pin head. You will also have to find a source for shims ( modified ones at that).

As Bob suggested, anyone listed on this site would be able to help with installation. I am aware of the Canada/US issue. I do not know what is available in "your neck of the woods" but now would be a good time to have the entire assembly checked- king pins, crack check, and to be sure the spindle is straight. Cheap insurance.

As for adjusters- can only guess as to why VW made the change. As with most of their changes, they were in anticipation of future model changes. The straights were used from 58 to 64 and the angled from 65 to 78.

Hope this helps
Dietmar
http://www.quixoteracing.com

(sent this earlier - pressed SUBMIT and it went to cyberspace so if this is a duplicate, my apologies)
Jean-Sebastien Stoezel
WCMA FV #0
Dietmar
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Re: Front axle preparation

Post by Dietmar »

Jean:

Vallis will do you just fine.

As for the advice- it is always free so don't hesitate to e-mail or call. Happy to help if I can.

Dietmar
http://www.quixoteracing.com
brian
Posts: 1348
Joined: June 26th, 2006, 12:31 pm

Re: Front axle preparation

Post by brian »

The adjuster springs are crimped on to the backing plate. Drive a screwdriver underneath the spring to pop it out and clean off the crimp and install another spring. Once in place, use a drift punch and dink over a section of the groove and recrimp the spring.
The above post is for reference only and your results may vary. This post is not intended to reflect the views or opinions of SCCA and should not be considered an analysis or opinion of the rules written in the GCR.
jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Re: Front axle preparation

Post by jstoezel »

Alright, thanks for the advice, will do.

Jean
brian wrote:The adjuster springs are crimped on to the backing plate. Drive a screwdriver underneath the spring to pop it out and clean off the crimp and install another spring. Once in place, use a drift punch and dink over a section of the groove and recrimp the spring.
Jean-Sebastien Stoezel
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hardingfv32-1
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Re: Front axle preparation

Post by hardingfv32-1 »

I have always thought that the angled adjuster help the lower part of the shoe function more efficiently by causing a slight downward movement toward/into the drum surface during brake application. It could also cause the shoes to retract from the drum, with the help of the lower brake spring, when the brakes are released. This could reduce drag, improve milage.

Brian
brian
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Re: Front axle preparation

Post by brian »

The purpose of the angled adjusters is to promote the centering of the shoe on the drum. As with any single wheel cylinder, fixed anchor system, the leading shoe will do more work and wear more quickly. Later brake shoe systems included a floating anchor system that minimized the wear differences. On the left side of the car the leading shoe is on the bottom; on the right side, it is the top shoe. Which is which is based on the rotation of the wheel.
The above post is for reference only and your results may vary. This post is not intended to reflect the views or opinions of SCCA and should not be considered an analysis or opinion of the rules written in the GCR.
jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Re: Front axle preparation

Post by jstoezel »

Brian:

This is going a bit outside of the front axle preparation but I've been meaning to ask. At least this is how it is setup on my car, I believe the front shoes are oriented top/bottom, the star nut and the wheel cylinders being aligned horizontally. This puts the brake line streamlined with the tierods which looks quite aerodynamic.

The rear is different though. At least on my car the shoes are oriented left/right, the wheel cylinder and the star nut being aligned vertically. Why are the front and the rear shoes oriented differently? Is this another odd modification on my car? Still I've seen this setup on quite a few cars and I think it's quite common.
Anyhow this setup puts the brake line at the top (12h) of the brake plates, which doesn't look very aerodynamic. It would be great if the brake plate could be rotated 90 degrees so the brake line attachment could be located behind the axle tube, which would seem a bit more aerodynamic. Would this change the efficiency of the braking at all? There was a picture of Mike Varacins car in a wind tunnel, taken from the rear, where you could see the rear brake lines at 12h, sticking out quite a bit. Can't find the picture anymore, but that was a good example.

That being said, I wonder if this modification would have any impact on the aero, considering there's still the rear tires in the way that generate a big chunk of the aero drag. Not to mention the pushrods and the leading arms.

brian wrote:The purpose of the angled adjusters is to promote the centering of the shoe on the drum. As with any single wheel cylinder, fixed anchor system, the leading shoe will do more work and wear more quickly. Later brake shoe systems included a floating anchor system that minimized the wear differences. On the left side of the car the leading shoe is on the bottom; on the right side, it is the top shoe. Which is which is based on the rotation of the wheel.
Last edited by jstoezel on January 25th, 2011, 4:12 pm, edited 4 times in total.
Jean-Sebastien Stoezel
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jstoezel
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Re: Front axle preparation

Post by jstoezel »

jstoezel wrote:Brian:

This is going a bit outside of the front axle preparation but I've been meaning to ask. At least this is how it is setup on my car, I believe the front shoes are oriented top/bottom, the star nut and the wheel cylinders being aligned horizontally. This puts the brake line streamlined with the pushrods which looks quite aerodynamic.

The rear is different though. At least on my car the shoes are oriented left/right, the wheel cylinder and the star nut being aligned vertically. Why are the front and the rear shoes oriented differently? Is this another odd modification on my car? Still, I've seen this setup on quite a few cars and I think it's quite common.
Anyhow this setup puts the brake line at the top (12h) of the brake plates, which doesn't look very aerodynamic. It would be great if the brake plate could be rotated 90 degrees so the brake line attachment could be located behind the axle tube, which would seem a bit more aerodynamic.

That being said, I wonder if this modification would have any impact on aero, considering there's still the rear tires in the way that generate a big chunk of the aero drag. Not to mention the pushrods and the leading arms.

brian wrote:The purpose of the angled adjusters is to promote the centering of the shoe on the drum. As with any single wheel cylinder, fixed anchor system, the leading shoe will do more work and wear more quickly. Later brake shoe systems included a floating anchor system that minimized the wear differences. On the left side of the car the leading shoe is on the bottom; on the right side, it is the top shoe. Which is which is based on the rotation of the wheel.
Jean-Sebastien Stoezel
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brian
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Re: Front axle preparation

Post by brian »

Not really sure why the shoe orientation is different on the rear except to say that on a beetle the suspension may be an issue. That orientation is true to the steet car and not a mod on the vee. On the aero issue, I doubt that anyone could measure the effect of rotating the backing plate but it's one of those feel good issues. I do know that having the bleeding screw in the 3 or 9 oclock position can cause issues when trying to get that last bit of air out of the lines. Don't know why, but the rears can be a real pain. I rotate the axle to put the bleeder at 12 oclock to bleed them. It means removing the locating nuts and bolts and loosening the hose clamp on the axle boot, but it has paid off in the past.
The above post is for reference only and your results may vary. This post is not intended to reflect the views or opinions of SCCA and should not be considered an analysis or opinion of the rules written in the GCR.
jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Re: Front axle preparation

Post by jstoezel »

Thanks for the reply, I think it makes sense to have the bleeding hole in the 12h position, as high as it can be, to allow bubbles to come up... I guess you could also raise the rear of the car when bleeding the rear brakes.

brian wrote:Not really sure why the shoe orientation is different on the rear except to say that on a beetle the suspension may be an issue. That orientation is true to the steet car and not a mod on the vee. On the aero issue, I doubt that anyone could measure the effect of rotating the backing plate but it's one of those feel good issues. I do know that having the bleeding screw in the 3 or 9 oclock position can cause issues when trying to get that last bit of air out of the lines. Don't know why, but the rears can be a real pain. I rotate the axle to put the bleeder at 12 oclock to bleed them. It means removing the locating nuts and bolts and loosening the hose clamp on the axle boot, but it has paid off in the past.
Jean-Sebastien Stoezel
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cendiv37
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Re: Front axle preparation

Post by cendiv37 »

One thing that helps a lot is to adjust the brakes up hard *before* you bleed them. This minimizes the fluid volume in the wheel cylinder by pushing the pistons in as far as they will go. Because it pushes the top piston down (in the 3- 9 o'clock locations), it also reduces the height difference between the bleeder and the top of the volume that needs to be bled. I think forgetting to do this is a large part of the problem people have bleeding their brakes.
Bruce
cendiv37
jstoezel
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Re: Front axle preparation

Post by jstoezel »

I'm continuing the preparation of the front axle.

As I was cleaning up the spindle assemblies and getting them ready to be shipped to a shop, I realized that yes it looks like the bushings are offset.
Is this amount of offset good enough?

[ external image ]
[ external image ]

I noticed that that bushing is not flush against the dog bone on this side (while it is flush on the other side). Is this of any concern?

[ external image ]

Do you think I still need to send these to be modified?

Also, I've removed the sway bar. It often comes lose, even if I tighten the allen nuts really tight against the turkey legs. I've had a few surprises with this car, so I took a few pictures of the bar, I want to be sure this is what is supposed to be installed.
It's a 3/4" bar, with flat inserts welded at each end.

[ external image ]

There's an adjuster at one end to get the turkey legs less loose against the beam. This is the side that I believe often gets loose. The hole that allows the screw to grab is a bit oblong, I guess that's to allow the side to side adjuster to have any effect when tightened.

[ external image ]


Does this look like a typical setup? How do you get the turkey leg to grab better the sway bar? Is 3/4" a typical sway bar diameter? I thought I had seen smaller diameters on a few FV websites.

JS
Jean-Sebastien Stoezel
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Dietmar
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Re: Front axle preparation

Post by Dietmar »

JS:

I'm going to guess and say that you have stock link pin bushings based on the pics. Place a link pin in the hole and measure the distance to the edge of the carrier. It should be smaller at 12 o"clock than it is at 6 o'clock.

On the sway bar: I have seen all kinds of "creative solutions" to fabricating a sway bar-this one is unique I have to admit. The person welded a flat to try to keep it against the inner square of the torsion arm by tightening the grub screw on the outboard side. All of my bars are square on the ends- this square fills the end of the torsion arm so that the bar can not rotate inside the end of the arm and then is located by the grub screw.
I would suggest having someone build you another sway bar.

Hope this helps
Dietmar
http://www.quixoteracing.com
jstoezel
Posts: 207
Joined: September 19th, 2010, 6:21 pm

Re: Front axle preparation

Post by jstoezel »

Hi Dietmar:

Thanks for the reply.

I measured the bushings, at 12 o'clock I get a thickness of 0.18", while the bottom is 0.20". This is consistent on all bushings.
Is this enough though, what thickness difference do you guys usually have?

Alright, looks like I will also be getting a sway bar. Do you have pictures of what it's supposed to look like? I guess I can't go square all the way, it's probably going to catch that square piece on the middle of the beam that's supposed to hold the springs.

JS



Dietmar wrote:JS:

I'm going to guess and say that you have stock link pin bushings based on the pics. Place a link pin in the hole and measure the distance to the edge of the carrier. It should be smaller at 12 o"clock than it is at 6 o'clock.

On the sway bar: I have seen all kinds of "creative solutions" to fabricating a sway bar-this one is unique I have to admit. The person welded a flat to try to keep it against the inner square of the torsion arm by tightening the grub screw on the outboard side. All of my bars are square on the ends- this square fills the end of the torsion arm so that the bar can not rotate inside the end of the arm and then is located by the grub screw.
I would suggest having someone build you another sway bar.

Hope this helps
Dietmar
http://www.quixoteracing.com
Jean-Sebastien Stoezel
WCMA FV #0
problemchild
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Joined: June 25th, 2006, 9:34 am

Re: Front axle preparation

Post by problemchild »

I much prefer your style bar than ones with the squares. It allows you to regrind the ends when the bar gets tweeked instead of throwing it away if it has square ends. The squares would be preferable if you did not have the grub screws .... but you do .... so you're only using one flat on each end anyway. Your style breaks less often too.

Check that both flats are on the same plain and grind if they're not.

The thing that is wrong with your bar is that there is a dimple on the draw-bolt end. Use a welder to fill the dimple and grind it flat. The draw-bolt then adjusts the end play and the grub screw is used only to clamp the bar in the turkey leg but not to locate it. The other end still requires the dimple which should be opposite the side with the flat.

You can buy other bars to try if you want, but your existing bar is probably easily salvageable. Many theories as to what you want. Most people want as big as they can get away with.
Greg Rice
"Happy 50th Birthday"
Dietmar
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Re: Front axle preparation

Post by Dietmar »

JS:

I tried to measure the way I suggested and it does not work. Tried three different "ready to go" carriers and they all measured differently, so sorry about the misdirection.

So, here is something that will work. Press the bushing out- does not have to be all the way. Can be done in a vise with a socket on the bushing, just enough to measure the end.

The offset bushing I have in my hand measures .175" at the end and if I go 180 degrees to that measurement point, I get .210". A new stock bushing will be .195"


As for the sway bar- I would NOT go square all the way - would make for a very stiff spring unless you removed the square in the middle of the beam. I have seen square bars installed with the bar ground with a grinder. (ugly).

Hope this gives you better results.
Dietmar
http://www.quixoteracing.com
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