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Date: Sat, 26 Aug 2000 10:11:26 -0400
From: "David A. Leonard" <>
Subject: [uuc] Dave's custom Electric to manual top 325IC Conversion

After acquiring a 1991 325iC , with a non-functional electric top (linkages bent like pretzels, fuses blown, motors disengaged), I set out to learn what I could about these tops. The net didn't have much help. All of the professionals, dealer and independent alike, made the sign if the vampire cross, and one even asked me how fast I could run when considering buying this car!

My conclusion was that fixing the electrics would be an exercise in expensive futility, and that a conversion to manual was in order.

The major problem is that it is necessary to lock the top cover down so it doesn't rattle or fly open at speed.

So anyway, here's my fix, it works quite well, and only takes about 2 minutes to put the top up or down.

  1. Remove trunk liner to expose motors.
  2. Use the wrench provided to un-lock the cover and top motors per the book procedure.
  3. Remove the linkage bar for the top cover (the metal leather covered piece that closes the top compartment) It is about 3 " long, and lifts the cover. it links to a ball joint on the top cover motor, and mine was bent double.
  4. Remove the cover over the top actuator motor in the top storage compartment and un-hook the long linkage bar that drives the top bows up and down.
  5. Unhook the other long linkage bar that is next to the one you just un-hooked, and remove it too.
  6. Un-bolt and remove the top motor from the trunk. Unhook its wires at its connector
  7. Remove the large relay module in the trunk that controls the timing of the two motors. when you take it off you will have a big connector plug in your hand. There are two big wires going to it. One is Brown, one is Red/Blackstripe.
  8. Go to NAPA, and buy SW-40, a Double pole Double throw momentary on switch, and some #14-16 pinch/splice wire connectors, some 18-20ga pinch /splice connectors, and a bunch of female spade connectors(insulated is nice), and get some 16 gage primary wire.

9 Splice into the Brown and red black wires one wire each, 2' long, right behind the big connector, using the big pinch/splice connectors. Run these to the center of the DPDT switch terminals,and connect with spade connector crimped on.

10 Splice into the Cover actuator wires(there are two), with two more 2' long pieces of 16 ga. primary wire ,and run these to one end of the DPDT switch, one to each terminal, BUT, connect a short couple of 6" long jumper wires into the crimp connector, one into each of the leads from the cover motor.

11. Put a spade connector on the end of each of these jumpers, and run each of them to the opposite side of the DPDT switch, crossing them so that the wire from the bottom of one side runs to the top of the other side and vice versa. The point of this exercise is that with the center fed + and - current , moving the switch one way will result in the motor running forward, releasing the top cover, and running backward, in the other position will lock the cover down.

12. Make up a neato black aluminum face plate for your toggle switch in the trunk, label it lock and unlock if you are one of those anal types, and drill a hole in the fiber trunk liner , mount your switch in it, and re install the cover over the motor.

13. When you want to put the top down, lift the cover, put it down, put the cover down, open the trunk, and toggle the switch down till the cover locks and the motor stalls. Let off on the switch as soon as it does. There is a 15 amp fuse controlling this circuit, in the fuse box. I haven't blown it yet, but I wouldn't make a habit of holding the motor stalled any longer than you have to.

PRESTO A Bullet Proof KISS manual top, with a clean electric lock down.

Note: when you put the top up manually, if you lift the front of the bow slightly, before you lift the back of the bow by the handle, it releases form the compartment with a lot less force.

I'm pretty pleased with this fix. It doesn't look like a kludge, and it is trouble free, and doesn't require much rewiring as it uses wiring and a fuse already present.

Good Luck, Dave Leonard (Topless this summer!)

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