koni rebuilding

[steve lapp]

Hello folks:

Back shocks have been leaking for a couple of years, so out they have come. I know Koni can rebuild them at modest cost, what I am curious about is how the heck they are put together. I got the threaded ring with the two holes off, but there seems to be an inner steel tube held in place by a rubber sleeve between the inner steel tube and the outer steel shell. Do they use tension to pull the shock apart to rebuild it? And the bronze fitting that the rod slides though, that has two slots that look like it should screw out. A quick webs search did not reveal a cutaway of this 82R-1322 type of shock. The shocks have the original manufacture date of 6-64 on them and no evidence they have ever been apart, so 45 years and 128,000 kms is not too bad a service life! Once Koni rebuilds the inards, can they supply the rubber spring mounts and donut jounce rubber?

Once they are rebuilt, how to you know what setting they are at, the shock setting is relative to what position of the top and bottom?

Tom. in Canada, is it only two weeks until spring! Hence my optimism about clean roads (we'll probably get a record March snowfall now).

Thanks and Cheers

[330GT]

... Once Koni rebuilds the inards, can they supply the rubber spring mounts and donut jounce rubber?

Thanks and Cheers

When I have the rears on my 330 GT, Koni did replace the silent blocks in the top and bottom mounts.

RearShocks2_small.JPG (12.51 KiB) Viewed 14813 times

However, the rubber boots were not included (I bought ones from Dunn - kaching!) nor the rubber spring pads (McCann).

MVC-376X_small.JPG (8.61 KiB) Viewed 14814 times

...

Once they are rebuilt, how to you know what setting they are at, the shock setting is relative to what position of the top and bottom?

Thanks and Cheers

If I remember, to adjust the shock setting, you push the piston all the way down and then engaging something in the bottom, rotate CCW to soften and CW to stiffen the shock. I just put mine in w/o checking anything, actually didn't think about it, presumably Koni would have left them set identically after their testing.

[John Vardanian]

Here are mine last year. The gray, black and red seals are replacements seals I got from McMaster Carr. Some I had to cut and same worked off the catalogue.

john

[steve lapp]

Thanks John for the pictures:

However, I can't tell from the pictures how the "inner" steel tube is removed from the shock lower housing. In mine, after removing the threaded retaining ring, there is some sort of rubber ring (it seems) holding the inner cylinder into the outer one - did you just pull on the shock rod to pull the whole inner cylinder out! You have metioned you bought all the seals, did you then do the rebuild yourself? I am now curious about self rebuild possibilties, did you do the whole rebuild yourself - who do you get the KONI decals from?

Thanks

steve

[330GT]

... who do you get the KONI decals from?

Thanks

steve

Parker Hall, of course.

[John Vardanian]

Hi Steve,

The tubes are not fastened. They just "dangle" in place. Yes, I rebuilt these by myself.

You have just removed the top threaded retainer ring and have come to see the rubber seal. You need to use a sharp pin to hook out the seal. At that point you'll see the retainer collar, which you will need to unscrew in the same manner as the top retainer ring. Once you do this the steel tube will free. Here is a good reference, but ignore Diagram B.

john

Legend:
1. Piston rod
2. Piston
3. Piston rod guide
4. Piston rod seal
5. Inner Cylinder
6. Reservoir tube
7. Foot valve
8. Bypass valve
9. Bypass spring
10. Adjusting nut
11. Adjusting knob
12. Adjusting detent
13. Compression valve assembly
14. Rebound valve assembly
15. Floating piston
16. Dust cover
17. Adjusting rod
18. Dust cap
19. Non return valve
20. Non return valve
21. Valves

A, B, C, D, E, F, G, H, J, K and L: Various orifices

[steve lapp]

Hi John:

Thanks for diagram. Now I see the inner ring below the rubber gasket also has two holes so the retainer can be removed. Mine is slightly different from the diagram, but the assembly appears similar. Koni is backed up to 10 weeks residence time for sick shock absorbers, so I think I am on the self rebuild route. I am assuming you just measured the seals and then searched McMaster Carr for the appropriate ones - but maybe there an easier method! i.e. did you keep the part #'s?

And one more question - the silent block bushings in each shock end, from??...need those too.

Thanks - will you be at the Radcliff Motorcar event?

cheers

[John Vardanian]

Hello Steve,

Have you looked at the McMaster Carr catalogue? I'll bet if you put "hen's teeth" in the search box something will turn up.

That said, some of the seals I was only able to find in either the right ID or OD. So I had to make a jig for cutting the seals precisely.

As for the bottoming out cushions, no one cares what these look like because they are completely hidden. You can get rubber or XLPE tubing on the whole range of the Durometer. Just get a foot of the right ID and OD and hardness, cut a section and slide it on.

I'll look at my old invoices to see if I can help you out. PM me your email.

john

[steve lapp]

Talked to Paul at Koni, rebuild time is 10-12 weeks at present, so the self rebuild route is now in action. I have sourced rod and wiper seals that can be fit with a little bushing I will make, and now I am trying to find what type of fluid goes into a shock aborber. Some websites say automatic transmission fluid. Web searches revealed little about shock abosrber fluids. Moss motors sells a fluid that seems to be used in all british car lever arm shocks, but is it appropriate for the Koni's? Viscosity and viscosity/temperature characteristics are obvioulsy important, but what specs to look for? An interesting side effect of all this shock work is an appreciation for what a complicated little piece of work they are.

Cheers

[John Vardanian]

Hi Steve, I used jack fluid.

john

[steve lapp]

Shock rebuild moing forward, housings bead blasted and painted, new seals in hand. One part I cannot find is the jounce bumper. No luck from Part Source or others to date. It is 1.866 inches OD and 0.733 inches thick with a conical cross section. I only need ONE! Any ideas? Are these typical on more modern shocks, maybe I can canibilize one.

Cheers

[steve lapp]

look at this

[John Vardanian]

Hi Steve, just get some rubber or neoprene tubing of the right ID and close-enough OD, cut off an inch of it and slide it on. Once installed, these never see daylight and it doesn't matter what they look like so long as they are there.

john

[Suebian330]

Hi folks,

as there is already a thread I continue. For my GT330 rear shocks I desperately search for the rubber boots Ferrari #600507. Since more than one year I tried already Rutlands, McCann, Eurospares and others. Some have them on their website to order, but wer´nt able to supply, some of them even do not respond. Others say no chance to get them. Does anybody know a source or any other part to adapt. I checked already standard suppliers in Europe but nothing fits.

"However, the rubber boots were not included (I bought ones from Dunn - kaching!) "

This is from the previous post under this topic. I can not find which supplier is meant.
Any advice?

Dieter

[Edward 96GTS]

Dunn as in Mike Dunn? (now deceased)