Rover SD1, Gauge Investigation

A sticking trip counter that won’t reset is a common “feature” of the SD1, and one that I’m keen to fix on my car.

Handily a spare speedo cluster was one of the parts I picked up on the weekend. This also had the sticky trip counter, so I decided to practice on this and if it works well then when I remove my cluster to swap the better lens over, I’ll fix my cluster too.

Heres the willing victim, legit Smiths gauges

You can see the lens although dirty is generally in good shape with only small marks on it. My current one was “marked” at the 60MPH/100KPH mark; obviously the previous owner had issues seeing the open road speed

Removing the lens is easy enough once the gauge is out, so working on the spare cluster, I removed the four screws and off came the lens

Another four screws and off comes the front surround

These four little nuts are the only things holding the speedo into the housing. Remove these (and take care of the little washers behind them) and the dial will pop out the front

This is the reset mech. The white lever gets pushed down by the button when you press it, which moves the little gears away from the numbers

I pulled the needle and dial face off so I could investigate the internals more and understand why it isn’t resetting

Button not pressed

Button pressed

At this point all the numbers should spring to zero. Clearly it isn’t working. On a whim I tried spraying some silicone spray onto the mechanism, and bam, everything freed up and suddenly it all worked like it should. The numbers all popped to zero

Now, obviously it’s a lack of lubrication in the mechanism that is binding it all together and making it stop working. I suspect that if you’re careful and drop a couple of drops of oil into the mech you may not even need to remove the needle and face. This is promising, next I’ll try on my real cluster and see if I can fix it.

Moving along, whilst here I removed the tacho to see why my one seems to show signs of dry solder joints. It worked occasionally, and when it didn’t a swift whack on the top of the dash would bring it back to life. It’d be nice to reconnect, fix it and have it working again. Three screws on the rear and out the dial comes.

Woo, 8 cylinder

I suspect this little board, being the only place with solder on it, is the source of my issues

Its stuck down with some double-sided tape, which I cut through with a razor. The solder is only on the top of the board, not through hole. There isn’t much room to work, but I suspect if im careful I should be able to clean up and resolder the joints on the board.

That’s where I’m at for now. I’ll need to remove my cluster and do some work to it, now that I have an idea of what im doing. Good start.