Dicky Rev counter - Volvo

[Chris_Robb]

I have a dicky rev counter (Volvo 2003T '91 vintage) that has gradually over the last 3 years got more and more intermittent, a now to the point when it only flicks on engine starting. This is the type without an engine hour meter.

I have visually checked the wiring and all looks ok.

The boat is in Greece, so it is not a case of wipping it off to get it tested, though I could bring it home at the end of this year and get it tested.

1. Could it be that the Alternator is failing to send a pulse? Likely or unlikely.
2. Are Rev counters repairable or do I just buy a new one.
3. If I buy a new one, is there a an alternative to a volvo unit (price?)

The lack of a working alternator does not worry me as I know from the sound what the revs are, but I just don't like things that are not working on a boat!

 

[West Coast]

Hi - encountered the same problem on a friends boat just the other week - 1993 VP 2003. Symptoms were intermittent tacho but also charging warning lights came on. All wiring ok, and engine panel seemed OK. Replaced alternator with a spare valeo unit, all OK again.

I also have a VP 2003, changed the alternator this past winter for a higher output one, 70amp, but with same footprint. Rather than expensive VP part, bought from Phoenix Electrical on ebay, alternator has been fine so far.

 

[Chris_Robb]

Hi - encountered the same problem on a friends boat just the other week - 1993 VP 2003. Symptoms were intermittent tacho but also charging warning lights came on. All wiring ok, and engine panel seemed OK. Replaced alternator with a spare valeo unit, all OK again.

I also have a VP 2003, changed the alternator this past winter for a higher output one, 70amp, but with same footprint. Rather than expensive VP part, bought from Phoenix Electrical on ebay, alternator has been fine so far.

Charge warning light is not a problem. I replaced the alternator in 2009 with a Prestolite 110 Amp/h and it worked fine - albeit with the revs too high as it has a slightly smaller diameter pulley wheel, but with a 13mm belt size which enables it to deliver 100amps with out slipping. Initially running on the 10mm belt the alternator would stall when the batteries were very low filling the boat with a cloud of smoke. Just changing up a size in belt totally solved the problem. I bought it from Adverc and said that they fitted the 13mm pulley for that reason!!! We digress.....

 

[Bongo]

Try changing the fuse block connector on the engine ( clear plastic x4 spades ) or plug into adjacent available spades..
does tacho come on again when you wiggle ( technical term ) the ignition key ?

 

[Chris_Robb]

Try changing the fuse block connector on the engine ( clear plastic x4 spades ) or plug into adjacent available spades..
does tacho come on again when you wiggle ( technical term ) the ignition key ?

OK - will try when I go back to the boat in September.

 

[charles_reed]

More likely the alternator end - if it's charging OK why bother about rpm?

However, you'd be well advised to carry a spare alternator - they only take about 20' to change.

Mine cost me €49. When you're in desperate need the same unit will go up to €150.

 

[corinthmistral]

Try changing the fuse block connector on the engine ( clear plastic x4 spades ) or plug into adjacent available spades..
does tacho come on again when you wiggle ( technical term ) the ignition key ?

Yes, I have the same problem and same solution. That fuse block constantly causes hassle and the symptoms you describe - as suggested, try wiggling the wires and see if that solves it. I really must get round to changing it.

 

[Chris_Robb]

More likely the alternator end - if it's charging OK why bother about rpm?

However, you'd be well advised to carry a spare alternator - they only take about 20' to change.

Mine cost me €49. When you're in desperate need the same unit will go up to €150.

It does not bother me, I just dont like things not working. Its been on my maintenance log now for 2 years!

I have the old Valeo alternator as a spare including the original wiring diagrams and belt - different size from new one.

As you know from Messy - I carry a spare starter motor as well! + fuel pump + seawater pump.....
PM being sent.

 

[Chris_Robb]

Yes, I have the same problem and same solution. That fuse block constantly causes hassle and the symptoms you describe - as suggested, try wiggling the wires and see if that solves it. I really must get round to changing it.

I will give the fuse block a complete clean up and see if that cures it.

Thanks for the ideas.

 

[Bongo]

I will give the fuse block a complete clean up and see if that cures it.

Thanks for the ideas.

Mine was making/breaking at odd times..I couldn't see the break ..change it if you can.

Good Luck.

 

[VicS]

I will give the fuse block a complete clean up and see if that cures it.

Thanks for the ideas.

The wiring digram in the owners manual (q.v.) only shows one fuse and that is in the + supply to the control panel.

Any problem with that fuse would likely also show up as a problem with the warning lights when switching on, the alarm and also with engine starting

Check it but aslo check the connections on the wiring harness including those for the tacho signal.

also check the connection to the W terminal on the alternator and the connections on the tacho itself.

It appears from the wiring diagram that the tacho illumination is on all the time. Checking on this should give an indication of whether there is a problem with the DC supply to the tacho.

An AC voltmeter , or even a small bulb could be used to check the output from the W terminal at the alternator and at the tacho itself.

 

[Chris_Robb]

The wiring digram in the owners manual (q.v.) only shows one fuse and that is in the + supply to the control panel.

Any problem with that fuse would likely also show up as a problem with the warning lights when switching on, the alarm and also with engine starting

Check it but aslo check the connections on the wiring harness including those for the tacho signal.

also check the connection to the W terminal on the alternator and the connections on the tacho itself.

It appears from the wiring diagram that the tacho illumination is on all the time. Checking on this should give an indication of whether there is a problem with the DC supply to the tacho.

An AC voltmeter , or even a small bulb could be used to check the output from the W terminal at the alternator and at the tacho itself.

Well perhaps that blows that theory out of the water then - as there are no other problems with warning lights and buzzers. Any thats the place to start with the alternator. I suppose a test of continuity on the wires might be worth doing - I have some long crocodile leads for the multimeter.