Replacing Dino 246 shocks?

Sage advice indeed. My mechanic (not Ferrari) used compressors until one let go under tension and nearly ripped his head off.

He missed quite a bit of time with that accident, but did recover fully.

No joke, they're called springs for a reason.

 

Scott,
A Arms are a welded assemly. Ball joint carriers are machined castings. The shims make up the slop left between the two. 4 was the center design. Plus or minus 2 on either side is reasonable. You are right, basic castor/camber are made at the chassis side of the A Arms. Plus or minus a few shims out on the ends make no difference worth noting. It is good to keep track of how many shims were used at each ball joint carrier and to replace the same carrier in the same A Arm with the same number of shims. If you don't, make sure that that there is no slop in the setup. Always nice to have at least one shim on each side if possible. Fit should be close on everything before you tighten up the bolts. Good luck.
John

 

Would disagree with you on that one John.

Those shims change the castor angle which is 4 Degrees. Any deviation to the positioning of the shims can change this (incidence) angle by as much as 4 degrees. If you draw a line through the centre of the upper and lower balljoints then the castor angle is offset by 4. The A arms are made that way on purpose.

Earlier cars didn't have the shims but later cars did i beleive. I was informed Ferrari adopted this method to take up any in-accuracies in the chassis during manufacture.


Cheers

Tony

 

I agree and am in step with you. Enough prior projects have resulted in my trusty clipboard next to me documenting the way things were disassembled and lots of photos of the removal.

Great advice, much appreciated!


SPRINGS?
I see huge piles of dirt but nothing that resembles springs yet.
Did I mention there is a LOT of dirt and crud in there?
OK, I'm joking about not finding springs....but did I mention this is a lot of dirt?
Chuckle...

Here's a photo of the fun starting
Image Unavailable, Please Login

 

Do you go rallying!!!!!!

If i were you, change the:-

Top and bottom balljoints
New bushes (be careful as the quality differs a lot and they do not come with the shims, you have to remove them from the old ones)
New Springs
New Shocks (unless you are confident they are OK)
New anti roll bar bushes
Get the upper and lower arms powder coated black
Get the nuts and bolts yellow passivated

Car looks sweet too.

Tony

 

Not sure I have full understanding of what you are saying, but I am confused.

What do you mean by 'clips'?

And I've used mechanical spring compressors hundreds of times to remove suspension springs from cars ... ofcourse if the car has adjustable spring platforms sometimes you don't even need them. As long as they are proper automotive and quality ones that hook over the spring coils properly they are very safe, just make sure you have 2 evenly spaced on each side and compress and uncompress evenly.

I'll be using them again very soon ... with nothing but the required caution whenever you play with something with that much stored energy. I most definitely would be more nervous about using a hydraulic one ... but then again I am not sure we are talking about the same thing .
Pete

 

I am not convinced that it is necessary to replace the 4 bushings on each corner. Don't confuse the cosmetic deterioration with compromised function.

If the intent is to clean everything up and repaint or powder coat the upper and lower A-arms (along with springs, etc.), then it may not be mandatory that the bushings be replaced. Yes, they are 35 years old, however, the mileage is not commensurate with the years. The age-impact on the rubber will be seen where the rubber is exposed. One will see cracking of the rubber. However, the business-part of the rubber bushing is hermetically sealed from ozone and environment in that it is compressed between the inner and outer bushing cans.

It is a pain in the rosey red r?ctum to cut the welds and press in new bushings. I have done it many times. And each time I have asked myself why I did it. If you clean the inner steel shaft and the i-d of the bushing and lubricate it, you will most likely find that there is smooth action without play. If it is a loose fit, then yes, the bushing should be replaced. But a nice, secure and smooth action is exactly what you are trying to achieve. One can sandblast or strip the A-arm and repaint, and not replace the bushing. In fact, you can purchase just the inner steel shaft, leaving the outer shell in the A-arm. This might well give you a new fit.

The rubber is not usually the problem. For those that have pressed out these bushings, I ask in what condition was the rubber? I have found the rubber to be fine between the two surfaces. It is the exposed rubber on the ends that reveals cracks. For cosmetic reasons one could take a razor blade and shave the crack off and retreat the exposed rubber with silicone.

Finally, with regard to the Konis, I have found a greater problem is stiffness from sitting for some time. When driving after a long period of inactivity, it often takes several miles for the shocks to soften up. Should they become too soft, I would unhook the bottom and leave the upper connection to the chassis. You must remove the upper rubber stop so as to allow the tabs and recesses to engage when placing the shock in full compression. At this point (full compression) simply rotate the shock clockwise to stiffen. I would turn the shock all the way clockwise, taking care to count the number of 1/4 turns it takes. This allows one to determine where they WERE set. Then rotate the shock completely counterclockwise to determine the full extent of the adjustment. Then go back to the original position and adjust to make stiffer. In this way you can assure that all the shocks are set equally.

In summary, I can only recommend that the bushings be carefully inspected before cutting the weld, pressing out, pressing in, and rewelding. If it ain't broken...don't fix it.

Jim S.

 

Why go to so much trouble Jim and then leave $200 worth of 35 year old bushes on the car!!! Cannot see the logic behind that to be honest. The guy has the suspension on the floor fixing it already? Did Omnjon leave his bushes on!

I quess most of us are guilty of fixing things if it isn't broke, we call it improvement or restoration.

Pete ;- If you have had success with Spring compressors then use them, i wouldn't and i certainly wouldn't recommend it either. Much more controlled on a hydraulic press, never found a manual spring compressor that compresses the dino springs enough.

The clips are below the spring stop. Half moon shaped steel rings. You have dig them out of the groove to get the spring off. To reinstall just re-locate them in the groove and then slowly release the springs so that it engages and locks in place.

 

Ditto, I bought a set of compressors to dismantle my springs/shocks, worst thing i ever bought! It was like an Englishman trying to play the bagpipes....... they now live in the corner of the garage with the Ronco and K-Tel sh#t i wasted my money on! Do you guys across the pond remember Ronco and K-Tel ? I have a suspicion that they may have been US companies.

 

Before I had my bushings replaced last year, the front end of the car would wander all over the place on uneven pavement. It was a little scary to drive fast over all but billiard table smooth roads (of which there are precious few in SC). While the suspension was apart, I also had new Konis installed. I didn't change the springs, as they seemed fine (maybe due to the fact that overall mileage was less than 30K at the time). Everything (a-arms and springs) got a fresh black powder coat before reassembly. The car was transformed by the new dampers and bushings. Best $6K I ever spent.

 

Ronco = Ron Popeil, I think he's still out there and for sure a US company.

K-Tel still puts out record compilations, see them on TV now and again. Also a US phenomenon.

UGH, I guess not everything from the Good Old USA is all that good.

DM

 

Dan and Tony -

I agree that it makes sense to restore these cars. However, from a practical approach, much of what we do is unnecessary. Most of these cars are low mileage, and bushing wear is related to mileage, not time. The rubber between the metal surfaces is rarely, if ever, the failure mode. It is the wear of the metal bushing that creates play. The rubber is protected. Thus, if inspection reveals that the metal surfaces provide a machine fit, then replacing them may make you feel better, but may not alter the suspension feel on the road. Changing the bushings is a major hassle. Cutting the welds, pressing out the bushing, pressing in the new bushing, and rewelding is not easy, and does introduce the potention to install the new bushings slightly askew.

It reminds me of the old coffee dispensing machines, where a cup would drop down and fill up with coffee for your quarter. There were two buttons for "Extra sugar" and "Extra cream". There were no wires on the back of those buttons! You would push one button or the other and feel much better about the extra sugar, but nothing changed.

Dan - did you change the tires after your suspension rebuild, or did you re-align the suspension? Both of these changes will significantly reduce the wander that you experienced prior to rebuild. I experienced the same phenomenon. The car would wander in the lane. After my rebuild, it was much better. However, I changed the tires and re-aligned the suspension, which I believe had much greater impact than the bushing change.

I only suggest that careful inspection of these metal parts might reveal that new bushings are unnecessary, and stripping and painting can be done to make the suspension parts look good without creating more problems.

Jim S.

 

Whilst i accept your reasoning Jim, i can change all the bushes in approx 3hrs (A frames on the bench)

I use a small grinding wheel (dremmel) to grind of the tack welds, press off the old ones and press on the new. Tack weld in two spots to stop them twisting. Before welding, offer them back in the chassis brackets to ensure alignment is OK. (99% of the time they are).

Word of caution, do not be too brutal with the pressing on & off phase, you can disform the A-arms.

Rubber deterioates with age and the quality of modern bushing material is far superior today than 35 years ago.

So yes it can be vanity but "if your gonna do the job, do it once"

Cheers

Tony

 

Tony is right, I'm changing everything and in the USA we can get the original, Italian bushes for FAR less than $200. I'll be putting a spreadsheet together and showing all.

Also, a friend works for local billionaire B. McCaw's Vintage Racing Motors (VRM) and I showed these ARMS/bushes to him. He's quite a Porsche racing guy and shook his head when I showed him the tack weld bushings and responded "Italian!"

DAVE - I just noticed that you've changed you avatar to a 360!
Does it have a compartment to store your POPEILS POCKET FISHERMAN in it?
(chuckle...)

 

Everyone,
I was flippant in my last post saying that a shim one way or the other didn't matter much. It doesn't but a batch of shims do. Sorry, lets start again.
A Arms and castings are a comfortable fit for 4 shims total. Good to start out with 2 and 2 when building up a new car. This means new bushings, new chassis, new bushing mounts on the chassis. Like Jon has just done on his Dino down in San Diego. Then you put the car on an alignment machine and pick the right shims AT THE CHASSIS to get everything dead on. There you can do anything you want with impunity. Camber, Caster! Once that is done things change over time. It is a PITA to go back to the machine. Caster can be changed independantly by changing the shims at the ball joints. That affects "feel" so anyone can notice it. Alignment shops will move a shim with no qualms. Any repair that does not involve pulling A Arms but does involve pulling ball joint castings should respect existing caster settings/shim count. If you are pulling the whole thing apart, as you are, you might start like the factory did, in the middle of the possible range. Hope this clarifies things. I am sure someone will call me if not.
John

 

Well, maybe. But rubber is an organic material that is subject to drying, shrinkage, and age. I don't necessarily agree that the fact that it's "protected" mitigates the aforementioned effects. I would not put 34 year-old tires in my car, even if they had been "protected" in a dark cellar for 34 years.

I did not replace the tires on my car, though of course the suspension was aligned after reassembly. As a side note, I do have to concede that I am now experiencing uneven front tire wear that has to be attended to. (Luckily I'm not running $400 XWXs!)

 

Check the bushes on a regular basis too.

I put a set on about 3 years ago and have just had to change them again. Only one bush failed and it may have been my fault but the suspension arm had quite a lot of play in it. This caused some tyre (tire)wear but "kickback" was more evident.

I used the hard rubber ones from Superformance, much better then the original. Cost about £100 GBP front set

Cheers

Tony