How to position the lower and the upper front wishbones?

[John Doe]

OK, I am in the middle of reassembly of my car and I need help. The front susprension is all new, all the bushes have been replaced, new shock absorbers etc. What I would like to know is how to position the wishbones?

Here is a photo

 

[angel]

Leave both wishbone pins and shock absorber lower pin loose and jack up the suspension until measurement H1-H2 is 80 mm, that is, center of driveshaft is 80mm higher than chassis rail underside, measured at wheel axis (just as we measure the ride height). At this position, tighten the pins.

Torsion bar should be off, or you may have trouble compressing suspension that much. Alternatively, you can use a tool similar to Renault's one.

Such nice restoration job must be followed by "as per the book" settings!

 

[John Doe]

Thank you angel.

Can I do it at this stage or I should wait for the car to be on its wheels? If I get this correctly at this stage I could measure only the distance from the center of the driveshaft to the chassis rail underside and it should be 80 mm? I can't use H1 and H2 since the car is not on its wheels.

 

[petak]

Is this proces crucial?

I thought that wishbones would positioned itself after mounting shock absorber and torsion bar in and lowering car on ground!

Or was it silly of me to think that this would be case?

 

[angel]

Vedran, it makes little difference whether you measure these heights against the ground or somewhere else, provided you have a fixed reference. The point is to position wheel centre 80mm higher than underside of chassis rail.

Petak, all rubber bushes on a Renault 4 are of the Flexibloc type, which means that rubber is bonded (vulcanized) to both inner and outer bush sleeves. Therefore, rubber is stressed in torsion when suspension moves up and down, rather than the sleeves sliding on the rubber bush, as would be the case in other cars.
By positioning the wishbones and rear suspension arms at a random position then tightening down their pins, you will end up with bushes that are constantly stressed, or working beyond their useful working angles, so they will wear out quickly (vulcanizing between the rubber and the sleeves breaks).
The factory setting is at about midpoint of suspension travel, so bushes are almost non-stressed with car unladen, and stressed towards both directions, when suspension is compressing and extending.
Think that we have some 20 cm of suspension travel at each wheel to realize that these bushes are working rather hard!

 

[iMacThere4iAm]

The abuse that these bushes can endure is incredible. I was just trying to remove a rear outer bush by drilling lots of holes in the rubber to weaken it until I could twist it off. Even after almost all the rubber was gone it was very difficult to break! Note for the future, it's a lot easier to burn those bushes out than drill them (but messier too).

 

[John Doe]

Thank you angel.

iMacThere4iAm, we had an epic battle with the lower wishbone bushes but in the end we won

 

[petak]

Hi!

I am in middle of this job right now and just want to be 100% sure that i get it right.

I will attach picture that shows measuring points on car.


Are this measuring position right one?
Did i get it?

 

[angel]

Yes, that is!

 

[petak]

Thank you angel!

I have read renaults manual and there is picture of measuring points but not so clear.

Think that this one clearly (and without any doubt) showing what you need to measure.

At the end i am more "visual" person. More learn by seeing something then reading