rpm counter

Hello, everybody!

I have been consulting your forum for a while now and it has proven to be of great interest and utility.

I have a question for you:

I have recently acquired a 55mm rev counter for my tatty 240 and have no idea how to install it. there are some three or four(I left it in the car) wires coming out of the instrument and I don't know where to plug them.

Does it require a sensor? Or can I just plug it somewhere?

Thank you all in advance, as you can imagine I am dying to be able to "watch the engine".

[Mike_Brace]

Is this a genuine 240 Volvo instrument? If it is one wire connects to -ve on coil then two pins to printed circuit. If after market one wire will be earth (possibly black) one will connect to coil -ve and their will be one power and possibly one for illumination - have to be trial and error. If you need help try posting a pic. Best of luck!

Mike

Thank you for your prompt anwser, Mike.

Yes, it is the original 55mm Volvo tachometer. My old tractor is a 1982 240 2D Sedan...

But you got me confused, now: I am not a native English speaker and don't know what the coil -ve is. Could you please explain?

Thank you again.

Tito
Finland

[Clifford Pope]

Have I got this right - you have a version with the big clock in the left hand space, and you want to swap it for the rev counter from another model?
I did this from an 86 GLT to an 89 GL that had only the big clock. The wiring was all there ready, it was just a matter of plugging it in. There should be a previously unused wire (yellow, from memory?) hanging out of the wiring harness, which you just plug onto the spare terminal on the new gauge.
If you still want to retain a clock you will need to take the small version from the donor car and fit it in the blank space just to the left of the main panel. You will need its bit of wiring too, which just extends the wiring from the old clock position to the new.

[Mike_Brace]

Coil -ve - The coil has two connectors. One is marked with a + the other with a -. This is what I meant by -ve. -ve = negative. On the 1982 model the instrument panel does not have provision for a 55mm tachometer. As Clifford says they replace the clock with a larger tachometer. However this 55mm instrument can be fitted elsewhere. You say your instrument has three or four wires. Could you tell us the colours?
If you have a picture it could be helpful.

Mike

Hello again, and thank you for your prompt advice.

The tachometer is to be placed on one of those two blanks in between the "junk box" (some models have the radio instead) and the instrument panel (which will remain intact). Please take a peep at the attached photo.

On the back of the counter there are two sets of cables, one for the illumination, other for the tachometer itself, which read : +, - and G.

I have tried pluging the G into the Alternator + empty spade and the + and the - to the battery, but to no avail. Nevertheless, by connecting these two latter into the coil, I immediately got ca. 900 rpm. The problem was that it did not respond very well to the acceleration, and in spite of some considerable throtle, it failed to pass the 2000 rpm.

In the back of the instrument panel there is one female spade on the left, which is unused and I don't know if it is + or -, and a male spade that is being used by a red and white cable. This latter I have tried but with no results. There are no loose wires except for a combined set of two(white and black & white) and an independent black which I presume to be meant for the fog lights.

Could the tach be damaged, am I doing something wrong?


Once again I thank you all for your keen interest
Tito

Another victory for the Volvo Club!

My many thanks to you all for your valuable contribution, especially to Mike:

I connected the G to the -ve in the coil and the rest was "a piece of cake". My mistake had been that I was assuming that G should be plugged to positive.

Now, please excuse me, I am going to take the tractor for a little drive. ;)

Tito

[Mike_Brace]

Hi Tito, So glad we were all able to help. There is a lot of knowledge out here. People only have to ask. Enjoy your Volvo! Best wishes from all us on the forum.

Mike