02.09
I drove my ‘87 Rangie home the night before, and it was running just fine. I don’t rebebmer if I worked on it or not, but the next morning it wouldn’t start. It didn’t even sound like it wanted to try. I quickly discovered that I had no spark. Great, the amplifier module is fried, and I don’t have a spare. I remembered hearing rumors that a GM module could be used with some minor modifications. I searched and searched, but could find no Rover related information about the swap, but I did find information. I found that the module I needed to try is a 4 wire module. The part numbers for the Chevy module needed are: NAPA ECHTP45 Wells DR100, Niehoff DR400, AC Delco D1906. So here is the story of what I did.
Here is the distributor with the cap, rotor and flash guard off, allowing us to see the wires we need to get at. I marked the location of the distributor, loosened the clamp bolt and turned it to allow the stock module to be removed. The bols holding it on have very small heads, 7/32 I believe. A small wrench is needed as there isn’t room for a socket.
After removing the module, you are left with a blue plastic plug sticking out. not having a matching little tiny socket, I grabbed it, twisted and ripped it off, leaving the wires exposed. I then pulled the wires out from inside and put my new wires (a piece of zip cord from a lamp) in. I used butt connectors to connect the wires together. A more elegant solution would be to buy one of the relocation kits as it probably has a plug and wires, keeping you from having to torture the distributor the way I did.
Since the new module won’t fit on the distributor, plus the heat from being mounted there is probably what kills most of them, remote mounting is required. I decided to mount it to the top of the wheelwell by the coil. I mounted it on a piece of aluminum with heatsink grease and then bolted it down. The connections are simple. The W and G terminals go to the pickup in the distributor. W is supposed to be the positive lead and G the negative. I have no idea which is which, but it shouldn’t matter much as the pickup will create both a positive and negative pulse. get it wrong and your timing might be off by a couple degrees at most. C goes to the negative side of the coil and B to the Positive. I put a ground wire on one mounting bolt as it should have a good ground. On my RR, the white wire goes to the B terminal, and the white with a black stripe goes to C. These were the original wires going to the distributor.
The stock amplifier module, and the small socket that plugs into the dizzy. NOTE! Do not break this module. It is made of berillium oxide, a wicked material that is much worse than asbestos. Some people also have an extreme allergic reaction to the dust. If it should break for some reason, wet it, seal it in a bag and throw it away. After getting everything hooked up, the Rover still had no spark. I double checked everything and found a wire that had come loose from a big glob of wires soldered together by some previous owner. After redoing the connection, she started right up. The connection was probably the problem the whole time, but I’m happy I did the modification as GM modules are cheap and easy to find.
