Rev Counter.

Don't know about yours but the newer diesels apparently have a connection you can use on the alternator. I bought a tacho from the people at

but I haven't gotten around to fitting it yet. I spoke to them on the 'phone and they were very helpfull, they maybe able to tell you if your alternator has such a connection.

The tacho I got from them is a very nice VDO one. I'll have to lose the clock and shift the other gauges to the right to fit it, but my radio has got a clock anyway.

HTH

Yea the newer alternators have a pulsed output like a coil pulse from a petrol engine that fires the tacho ...... a series landy alternator (if it is standard) doesn't have this output so fitting a tacho is not a fesible proposition unless you can make a gearbox drive for a mechanical one from the alternator .... not an unskilled job !!!!

Gromit

You used to be able to get tachos which read the pulses on the LT side of the coil and used that to derive the rev range.

You had to get the specific one for your cylinder count tho.

P.

But he wants to fit one to a diesel so no coil and the alternator output is a lot higher(faster) than a coil so if you connect a petrol one to an alternator it would read very high tickover 10,000 rpm ?

Andy

On or around Wed, 12 May 2004 19:53:16 +0100, "Andy.Smalley" enlightened us thusly:

you'd need a rev counter that was designed to run off an alternator. Never been entirely convinced of this - even assuming that the various makes and models of alternator are the same output frequency per shaft speed, not everyone uses the same size pulleys.

I've seen a 6-cylinder diesel in a pulling tractor which had a distributor fitted so as to give rev-counter pulses.

The VDO one I got from lowtension is supposedly universal. It can be fitted to both petrol and diesels. There are dip switches to set the petrol side of things like the number of cylinders. For diesel use you need an external tacho so that you can calibrate the VDO one running off the alternator pulses.