Link Pins loosen up

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David Jones
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Re: Link Pins loosen up

#31 Post by David Jones » Wed Nov 20, 2019 8:25 pm

The upper and lower arms can be swapped side to side. I just did it on my cab to get rid of a persistent shake that I could not track down. Everything checked out OK but the swap of torsion bars and arms side to side made the biggest difference. I still have a slight shake occasionally at around 60 mph which I now attribute to road surface anomalies and the fact that cabs like speedsters are flexy fliers unless one does some serious stiffening of the chassis.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
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Harlan Halsey
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Re: Link Pins loosen up

#32 Post by Harlan Halsey » Thu Nov 21, 2019 3:23 am

Jon,
Didn't work that way on the set I have on the '56. The pin hit the edges of the rings, big interference. And no the arms were not bent. So may be these arms are odd. I had carelessly assumed that the were all like mine.

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Re: Link Pins loosen up

#33 Post by Jon Bunin » Thu Nov 21, 2019 4:18 am

Harlan Halsey wrote:
Thu Nov 21, 2019 3:23 am
Jon,
Didn't work that way on the set I have on the '56. The pin hit the edges of the rings, big interference. And no the arms were not bent. So may be these arms are odd. I had carelessly assumed that the were all like mine.
Harlan, I've had that P70 since the late 80s and have checked hundreds of arms. If I only check 2 cars a year (= 8 arms) that would be 240 arms in 30 years, but people sometimes bring me boxes of arms to check.
I don't remember having any complete no-go issue with the bracket ring. Sometimes the bracket's bent a bit and needs to be straightened, no big deal. So I can't explain the problem you had. People bring me filthy, heavily rusted or powder-painted arms, which take more time & effort for me to clean up than they do to check.
Jon Bunin

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Harlan Halsey
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Re: Link Pins loosen up

#34 Post by Harlan Halsey » Thu Nov 21, 2019 7:29 am

Damn, and here I thought the bore sight laser was such a good idea!

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Re: Link Pins loosen up

#35 Post by Brad Ripley » Fri Nov 22, 2019 5:05 pm

Jula asked about a tool to check the C-links. This is a tool that Paul Christensen made to check for twist and compression. See photos below. If the C-link is not bent, it will go over each dowel pin very nicely. Also, it should go tightly down against the base on both ends. Note the offset machined into the base to represent the offset between the top and both of a perfect C-link.
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Harlan Halsey
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Re: Link Pins loosen up

#36 Post by Harlan Halsey » Sat Nov 23, 2019 5:13 am

As part of a king pin job, of course I always have everything magnafluxed. The C-links get special attention because they can crack and break. (The Baja buggy racers have a weld on fix for this but I think that is overkill for other than off road racing.) I polish the corners by the "veep and T" in the above photograph, with a Cratex wheel before I take the parts over to Doug at Techcraft for mag.

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Vic Skirmants
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Re: Link Pins loosen up

#37 Post by Vic Skirmants » Sat Nov 23, 2019 9:37 am

Harlan Halsey wrote:
Sat Nov 23, 2019 5:13 am
As part of a king pin job, of course I always have everything magnafluxed. The C-links get special attention because they can crack and break. (The Baja buggy racers have a weld on fix for this but I think that is overkill for other than off road racing.) I polish the corners by the "veep and T" in the above photograph, with a Cratex wheel before I take the parts over to Doug at Techcraft for mag.
It is also critical in road racing. Yes, we broke plenty of them early on.

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Juha Vane
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Re: Link Pins loosen up

#38 Post by Juha Vane » Sat Nov 23, 2019 3:10 pm

David, please send me the photo of the C-link you plan to have machined. TIA

My link pins was not actually loose, they are worn and have to be replaced.

The CSP link pins are "Febi Bilstein" so should be good quality.
CSP claim that their link pin set fit also 356? Please see enclosed page:
https://www.csp-shop.com/en/front-axle/ ... 2302a.html

CSP also claim that their C-links fit 356?
https://www.csp-shop.com/en/front-axle/ ... 0826c.html
Have no way to check if mine are OK, so safest is to purchase new parts.

Would someone be kind and tell if these could be used in a B T6, if known.
KTF,

Juha Vane
Finland

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'63 356
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Re: Link Pins loosen up

#39 Post by Martin Benade » Sat Nov 23, 2019 3:21 pm

The o rings and metal plates for them are VW style and will not fit. You would have to reuse your old ones or leave them out which is not ideal. The C- links will fit for drum brakes but you should be ok just replacing the bushings and king pins, but will require pressing and reaming to size.

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David Jones
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Re: Link Pins loosen up

#40 Post by David Jones » Sat Nov 23, 2019 3:37 pm

Juha as Vic concured in an earlier post, the "C" link is the same for all 356 models but as of the 1955 model the inner face where the "C" link contacts the trailing arms was machined by Porsche for reasons unknown. The link pin bushings that Porsche installed are bronze instead of the sintered steel used by VW which can only be because Porsche thought bronze would wear better or more likely because VW wanted to save money on cost of bushings. I have never used the bronze bushings only because I have the time to maintain my own cars and from using the sintered steel bushing in the F Vee found that there is no functional difference in them just initial cost. The Porsche link pin set costing about 130% more than the VW set and as the difference is in the link pin bushings and the rubber seals then it may be surmised that you are paying for the bronze bushing as the link pins and shims are identical. If you grease them at the recommended intervals they will last as long as you are likely to be driving the car. It is an often neglected area of the car and many mechanics do not know that the weight should be off the front suspension in order for the grease to penetrate the king and link pin bushings when greasing them.
Refer to the picture posted by Brad and your own linked picture for the difference, though when I return from the garage in an hour or so I will get a picture of a raw VW "C" link and post it
As for checking yours for straightness I would suggest that if you were to offer up your "C" links to the trailing arms with the bushings and the link pins installed with the correct number of shims and the arms compressed to the correct distance to allow you to slide the link pins into the arms you will see immediately if there is anything bent as they will not mate correctly. The pins will slide into the arms with very little resistance and the camber of the wheel will be very close to correct and if it is out at all it can be corrected by adding or subtracting shims from the "C" link. Most of the time on street cars I work on I find that worn out link pins and bushings are common and have only had 2 that were bent, one "C" link and one trailing arm.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
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Dick Weiss
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Re: Link Pins loosen up

#41 Post by Dick Weiss » Sun Nov 24, 2019 1:57 am

What's never mentioned is possible rattles could be from the worn shim on the kingpin assembly.
The fiber shim comes in several thicknesses to get almost zero clearance of vertical movement
of the stub axle--even thin metal shims can also be used to finalize the fitment before adding the
kingpin. Using a press I've straightened a couple of trailing arms years ago and including several
C links to get the alignment to specs.

Also, I separate the greasing of kingpin ends and the linkpin bushings by adding grease nipples near
the existing nipples (1/4 X 28 fine threads)--making sure the bushing holes are aimed away from
the kingpin ends. When greasing the front end, I raise the car, add grease, lower the car & lightly
grease again. BTW, age-clogged grease nipples & all holes during disassembly must be cleaned out!

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Mike Wilson
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Re: Link Pins loosen up

#42 Post by Mike Wilson » Sun Nov 24, 2019 12:21 pm

Joris asked if anyone straightens the arms. Touch base with Ed Rutherford at Klasse 356. He found someone that does.

Mike
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Mark Sabbann
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Re: Link Pins loosen up

#43 Post by Mark Sabbann » Sun Nov 24, 2019 7:14 pm

David Jones wrote:
Sat Nov 23, 2019 3:37 pm
... many mechanics do not know that the weight should be off the front suspension in order for the grease to penetrate the king and link pin bushings when greasing them.
And I guess I am one of them, Thanks David for the insight!
Mark Sabbann
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David Jones
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Re: Link Pins loosen up

#44 Post by David Jones » Sun Nov 24, 2019 10:45 pm

The cheap way to check if the "C" links are bent or twisted, unless they are both bent exactly the same amount. They are mirror images of each other. Just place them together as in the picture.
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If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
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Harlan Halsey
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Re: Link Pins loosen up

#45 Post by Harlan Halsey » Mon Nov 25, 2019 4:36 am

Clever suggestion!

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