Compression of bumper shocks .

dcioccarelli

dcioccarelli

Dominic Cioccarelli
Hi all,

the other day I removed my front bumper in the hope of compressing the bumper shocks so that the bumper could sit closer to the car (I realise that this is not always a good idea, but I'm prepared to take the risk).

In any case, I had understood from a previous post that it was just a matter of releasing the oil in the shocks by hitting a plug somewhere in the centre of the shock absorber. Looking at my one, however, I can't find any hole and it is possible that it isn't even a shock absorber that I have fitted to my car.

After removing the bumper, I'm greeted by two squarish / oval shaped tubes that the bumpers mount on. If I stick something into these, they seem relatively hollow.

My car is an '87 US import, therefore I would expect it to have shock absorbers for for the bumpers. So my questions are:



Thanks in advance,
Dom.
 
Just did That :)

And I learned a few things:

1- Remove back bumper (back is easier because nothing attached to it)
2- Prepare a drill with a fine bit and a punch
3- With back end of car lifted for more ease, punch a little dent in the shock near the front (mount) of it or where the drill will have easy access.
4- Drill directly in the shock until you hear a loud PSHHHHHHT and a cloud of clear gas comes out. (yes it was gas to my great relief no mess)
4a-Repeat on other shock
5- Use a losening (WD40) spray liberally on both shocks to help them collapse when you hit them.
IMPORTANT: reattach the bumper BEFORE you collapse the shocks! If you don't it will be almost impossible to fit a wrench or anything back there to bolt back on.
6- With the bumper on there, Grap a short 2x4 and hammer away at the bumper positionning vertically on the shock position and alternating left right left right to help even things on both sides.
7- When happy with the position, try to move the bumper by hand. It should not move. Mine has been like this for 3 weeks and I've had no rattle.

Front is the same except you have to remove fog lights and blinkers UNLESS you're a lazy bum like me and just let the bumper stand on a 2x4 and you don't mind fighting with a hanging bumper while you work.
The front shocks were harder to collapse and be sure to use a LOT of losening spray. I actually had to collapse the shocks before re-assembling the front bumper as they would not go in with the bumper attached. I had to collapse then pull out again (WHICH WAS A PITA) and mount the bumper again.

I'm REALLY happy with the end result and it took me a full hour.
I painted the whole thing black directly on the aluminium and it adds to further the slimming effect of the operation. ABOUT 2" was gained on each end :)

I posted before and after somewhere on this forum. :)
Before:

After:

good luck
 
Last edited:
Dom...

The front bumper shocks are held in place by a single cross bolt at the rear (accessible from under the car near the radiator) and by a single pinch bolt at the front, that compresses the front of the metal shock housing around the rubber boot that centers the shock in the housing. There's probably a better way of describing it, but that's the best I can come up with on the fly.

I'm almost positive that the larger rear bolt can be removed with the radiator in place, but it takes patience (it's been years since I've done it but hopefully my memory is correct). Seems like the smaller front bolts are pretty easy to access but it can be a bit of work to coax the rubber boot out of the shock housing.

As far as I know all of the cross rail style bumpers (early ladder style and later one piece style) were mounted on compressible "shocks". They do indeed contain pressurized oil. I'm not aware of any plug that can be knocked out to depressurize them, but I'm not sure I'd wanna use that method even if there were. The shocks contain a fair amount of pressure so just knocking a plug out would make a big mess (about like driving a nail into a partially full spray paint can).

I drilled small holes in mine in order to vent the pressure. Chucked 'em in a vice on the drill press and drilled through a shop rag in order to contain the oil spray. Still wound up with some on the walls.

If you do decide to go that way be sure to wear safety glasses and expect a bit of a mess if the shocks are still under full pressure. Note that the shocks are pretty heavy though, so if you're interested in performance you might want to consider making some new mounts out of lighter material rather than modifying the existing ones.

HTH and let us know how you decide to go about it,

///Mike
 
bumper shock compression

did this on my 82 couple years ago
there is a pin in the end of shock hit with center punch (see pic)
mine were filled with oil.

bumpshock.jpg
 
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