1988 – 1989 Buick Reatta Radio Capacitor Replacement
This information is provided for those who have the specialized tools, and a high level of expertise, required to perform the work. Safety should be observed in performing any electrical work to your car. Use this tutorial at your own risk. This website accepts no responsibility for the outcome.Background:
Many Reatta Delco radios cause popping sounds in the speakers because 6 green capacitors need replacement. The model number of the unit discussed here is 16072780 and it is AM/FM Stereo w/equalizer.
Remark: These instructions are for the most part just further documenting the information previously posted on the Buick Reatta forum by Saheim on 12/5/02.
Note: The following assumes that the radio's heat sink (black color) is at the back.
Read all the instructions below before starting this project to determine if it is within your capabilities.
Remove one ¼” hex head screw #A (see photo) at the front of the radio, and lift up the top steel cover to remove.
De-solder the top circuit board from steel case at 2 locations and bend tabs with pliers, so as to separate circuit board from steel case.
Remove ¼” hex screw #B on right side of case and also ¼” hex head screw #C at right front of the steel case.
Now lift off top circuit board to expose bottom circuit board.
Next, remove four 3/16” hex head screws from top of black heat sink.
Then remove a T-15 head screw (sometimes this is a ¼” hex head screw) from each side of the heat sink (no photo), and lift off the heat sink.
On the two rails that support the heat sink is a white heat conducting compound. Leave it on – it is necessary. Six green capacitors that are to be replaced are now visible.
Next remove a ¼” hex head screw from the bottom circuit board. It is near the front left side corner (see photo).
Then remove a 3/16” hex head screw #D from just under connector plug sockets on the right side of the steel case (see photo).
Now you can lift up the bottom circuit board out of the steel case. It may not just pull out because of some binding, but gentle prying will free the circuit board.
The above procedures will take you 5 to 10 minutes if you have the tools ready.
The 6 Delco green radial capacitors are each 1uf 50 volts and are 5 mm high and have a diameter of 5mm. I obtained replacements from: http://www.mcminone.com and their part number is: 31-8565. The size of the MCM capacitors is 5 mm high and diameter of 4 mm. Usually the 1uf 50 volt capacitors that are obtained are higher and must be bent over when mounted on the circuit board due to heat sink clearance requirements, so usage of the MCM product made the job easier.
I have never been proud of my soldering skills and had zero experience with circuit boards, so I consider the removal of the 6 green capacitors and the installation of the replacements to be a bit difficult. In addition, a pro might have a different procedure, but here is how I accomplished the task, which took me about 90 minutes:
First, I marked the location of the wire leads of the old capacitors on the underside of the circuit board with a red felt tip pen. When I heated the underside wire leads and pulled at the top of a green capacitor with needle nose pliers (or a hemostat), usually the body of the capacitor would pull away from the two wire leads which were left in the circuit board. I would then pull at the leftover wires from the top of the board while heating the solder from the other side.
However, after removal of the capacitor’s wires from the circuit board, the holes had closed up. (If I had a solder sucker, that might not have happened – but I don’t know). Heating two holes from one side of the circuit board while trying to thread the two wires from the new capacitor was more of a challenge than I could handle.
My solution to the problem was to use a jeweler’s drill bit (size 60 or smaller) in a pin vise so as to make new holes where the old capacitors were previously installed. I was careful to make a diagram as to where each of the new capacitors should be mounted, since many are quite close together and it might be easy to mix up where the wire leads should go.
Now each of the new capacitors was soldered into place and the radio was reassembled.
Remark: My radio was making a popping sound perhaps only once every minute or so and wasn’t really annoying and otherwise sounded fine to me (although I don’t have a good ear for sounds). With the replacement capacitors, the popping has completely disappeared, but for some reason the overall sound quality seems significantly improved. Sound now seems clean and crisp – perhaps there used to be some high frequency static that I didn’t consciously detect.