I have been up to my neck in Volvo speedometers for the last two days. I have learned several things.

In reference to the 140mph speedometers in the 7/9 series.

I can tell you that the 1991 and 1992 instrument clusters and their speedometers are the same. 1993, 1994, and probably 1995 are all the same but different from the 91/92. The speedometers from a 91/92 cluster will not swap with a speedometer from a 93/94/95.

It would appear that the 960 cars share the same cluster with their respective 740/940 cousins. I was able to swap a speedometer from a 92 960 with a speedometer in a 92 940. Turbo cars require the tachometer/boost gauge to be swapped into a replacement cluster from a NA car.

While speedometers will not swap between the already noted clusters, I believe entire clusters will swap across the 91-95 models. The clocks are a wild card in that some are controlled from the dash and others through the bezel. I did not investigate the cruise control. 91/92 have a male spade on the speedometer and the later cars have the spade on the back of the cluster- I would guess both are providing the same needed signal but I did not have the opportunity to check this out.

In reference to speedometer disassembly.

David D’Angelantonio’s file (http://www.brickboard.com/FAQ/700-900/ElectricalSpeedometerRepair.htm) with photos is a great resource in repairing the Yazaki by replacing the capacitors. However, the disassembly calls for quite a bit of unsoldering connections on the board including a ribbon with multiple joints. While I am comfortable unsoldering/resoldering joints on a board I find working with ribbon fraught with chances of error.

He calls for no less than 11 unsoldering points (5on a ribbon) to disassemble the speedometer. I was able to reduce the number of unsolderings to just two. Those would be the blue wires that connect the micro switch to the board. After disconnecting those from the board the remaining disassembly was only involved with removing the needle and some screws.

Begin by removing the needle. Gently rotate the needle by hand to it stopping point and note (or mark) this point which is more or less the “m” in the mph at the bottom of the face. The needle is then twisted off by very gently turning it and lifting straight up after you carefully lift it over the zero peg. Yes, scary stuff, but would you rather unsolder and resolder the remaining 9 solder points? Pick your poison.

Continue on the other side by removing the four small Phillips head screws near the center of the board. Only two of them really need to be removed but it is hard to tell which ones they are until you have taken the board loose.

At that point the board will come loose but still be attached by the ribbon cable on the motor. With the board loose you have access to both screws that hold the motor in place. Remove those two screws and the odometer motor lifts free and stays with the board. You now have access to the capacitors that are referenced in Davide’s tutorial.

You can further disassemble the remaining portion by using a knife to separate the face from the clear plastic structure. Gentle prying of the face all around will pull the adhesive points loose and the face will come off. The adhesive remains tacky and simply press the face on for reassembly. The removal of the face will reveal two small Phillips head screws that when removed will leave the mechanical portion of the odometers free of attachments.

Assembly is straight forward based on the disassembly. Care needs to be taken to see that the pin in rotated all the way clockwise to its stop before pushing the needle on at the stop point you found before taking it off.

Invest in a good screw driver set capable of giving a good fit to the screws you will encounter. Husky (Home Depot) makes one I like that has four different sized inserts- slot on one end and Phillips on the other.

In addition to everything I learned about speedometers I also learned that the thin “zero pegs” on the temperature and fuel gauges are very fragile and easy to break off….

Some of this material is already sited in the FAQ’s but I included it here for continuity. I did not learn it all on my own. Thanks to those who contribute to the FAQ’s and to Steve Ringlee for all the work he does in organizing, arranging, and making sense of the contributions.

Randy