Subject: Bringing In Bumpers

x-sender: e21autos@popd.ix.netcom.com Date: Mon, 18 Aug 97 03:59:22 +0000 Mime-Version: 1.0 Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: Quoted-Printable 0001 Content-Length: 7667

by Peter E. Galloway (with notes from Brian Jarvis, who, with much appreciated assistance from his father, completed this process over a weekend!) Taken from Roundel - February 1983 (pg. 42-43)

Hate that battering ram front bumper on your 320I? It just doesn't look right does it? One of the many Big Brother edicts designed to protect us from ourselves. Well, it's one thing you can do something about. Take a look at figure 1. How's that for an improvement? It looks more like the car was meant to. It looks more European!! Of course, it will require defeating the five mph shock absorption capacity of the front end, something you might not car to sacrifice if you are prone to bouncing you're Bimmer off firmly anchored objects at those speeds. But if you are more interested in good looks like me, you're probably broke from having coughed up a truck full of bucks just to have the privilege of owning The Ultimate Driving Machine. If so, you'll be delighted to know that it shouldn't cost more than a few pennies and take about two to three hours of weekend labor. All that's required is a few basic hand tools, a couple of machine screws, some contact cement or something equivalent. A friend to help wouldn't hurt, but you can do it yourself. If you are interested, read on.

What's entailed is the removal of the front bumper and the shock absorbing units, collapsing of the shocks, some modification to the rubber side moldings, and re-assembly. It's about as easy as it sounds. The first step is to see that you have all the necessary tools. You'll need an assortment of metric wrenches, both regular and socket, a drill with bits, a hack saw, two #10-24 long round head machine screws, a 10-24 tap, a screwdriver, rubber mallet, some sort of disc sander, if available, and possibly a round file. Some contact cement will be needed to rejoin = the shortened side molding accordion, although I used Goodyear Pliobond.

(BJ=EDs note - Wet-suit cement for neoprene from a diving shop works great. It stays pliable at all temperatures.)

One more item, a pair of goggles or some sort of mask. You'll find out why later. First remove the 10mm nuts securing the side reflector/bellows units to the front fenders

(BJ=EDs note - The bellows should still be bolted to the bumper with two bolts each. Do not attempt to remove the bellows units from the bumper itself YET. They come off the bumper once the bumper is off the car).

There are two for each side bellows and these are accessible through the front wheel openings inside the fender

(BJ=EDs note - Raise the car up on the side your working on with a jack - The increased gap bet- ween tire and fender makes it easier to remove - and later put back on the moldings).

With a socket wrench, remove the four 13mm nuts that secure the bumper to the shocks. If you have fogs, you'll probably have to remove them from the bumper before you can get it off. Just let them dangle by the wires until reassembling. Remove the reflector side moldings / bellows from the bumper now and put those pieces aside until later. Next, remove the shocks from the car. Two bolts secure each one. Once is readily visible and can be removed from inside the engine compartment with a 17 mm socket. The other is buried behind the grill, but can be accessed through the wheel openings and through the cut-outs behind the head lamps. The latter will require a 13mm socket wrench with a short extension. If you have a car with air conditioning, you might have to file a slot in the rectangular hole through which the right shock protrudes. This is to allow room to raise the copper tubing connecting the compressor to the condenser coil in front of the radiator so that you can remove the right shock. A large diameter round file and a little elbow grease should take care of this nicely. You'll have to rotate each shock about 90 degrees in order to remove it. Since these shocks are gas filled with oil damping

(BJ=EDs note - Don't worry. It isn't harmful to skin or paint. Its like mineral oil.)

all that is needed to be done is to release the pressure that keeps them expanded. Drill a 5/32 diameter hole in the top of each shock, about 2 inches forward of where the round portion is welded to the rear mounting bracket. This is where you'll need goggles as oil will squirt out when the pressure is released. With a rubber mallet or piece of lumber, hammer the shock until fully collapsed. Oil will squirt from the hole you just drilled, so be sure it isn't pointing towards you.

(BJ=EDs note - This IS very important! It IS messy and it DOES squirt out! Shake the shock to get out as much oil as you can before wire brushing / priming / repainting.)

When the shock bottoms out, you should find that its length is shortened by almost 2 '. Compare the two shocks for length after doing this to be sure that they are the same. Now each shock has to be anchored closed so that it doesn't gradually open with time. Since the other end is free to rotate relative to the inboard end, you must be sure that the bumper mounting brackets are square to the inboard end of the shock. Check it with the straight edge as shown in figure 7. If they are out of line, rotate each appropriately until they are lined up. Having collapsed each shock and checked their alignment, using the hole you drilled as a pilot, drill through with the 5/32 drill bit into the center gas chamber of the inner (smaller diameter) tube until you break through. This time, gas under pressure will be released, so try to guard yourself against a gas/oil shower by wrapping a loose rag around the drill bit. Don't try this without some sort of eye protection. After wiping the oil spray from your face, use the 10-24 tap to thread the hole and insert a 10-24 round head machine screw. Stainless steel screws are preferable, if available. Sock them down tight and reinstall the shocks. Replace the bumper on the shocks BUT do not bolt in place yet! With a hack saw, cut off the tabs on the plastic skirt which bolts to the body and lies under the top surface of the bumper. Now cut the five rear most accordion elements from each side molding. You'll find that a hack saw will do a better job than a knife.

(BJ=EDs notes - I found it easier and more accurate using a pair of gardening/pruning snips and safer to make just one cut in each side bellows at first, creating two pieces-the fender-mounted piece and the bumper-mounted piece. After reattaching the fender-mounted piece back on the fender, you can slowly cut segments of the bumper-mounted piece away and check the fit after each pleat is cut. When you get to the final fit, remove the fender-mounted half and use a disc sander to sand the two new mating surfaces to provide a uniform flat contact surface. This is necessary for a neat appearance as well as to provide for a good bond between the two halves to be joined. Reinstall the fender-mounted segment (remember, the one with the reflector) back on each fender and the bumper-mounted half to the bumper. Lastly, apply contact cement

(BJ=EDs note - Like I said, dive suit cement works well.) to the halves of the side moldings and allow time for the cement on the two halves to partially dry before reattaching the bumper. Reinstall the fogs and you're done.

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