Vitesse Mk2 - Seized Rev Counter

[Phil C]

Evening all

Rev counter stopped working recently.

After further investigation I found the rev counter input had seized. The cable is brand new so wasn't going to give way so the plastic drive in the dizzy was sacrificed!!

I can sort the dizzy but what to do with the rev counter.

Is this a DIY job?  I've never dismantled one and they look rather fragile - it has the potential to go horribly wrong.

Or should it be sent off to the experts (expensive?) and if so any recommendations?

Any thoughts most welcome.

 

[Colin Lindsay]

Second hand come up for sale all the time - currently £40 on eBay. As for repairs, expensive probably. There was someone on eBay recently selling electronic conversion kits for our cable-driven tachos, but he seems to have stopped advertising.

[johny]

yes probably cheaper to get second hand than professionally repaired. However worth taking yours apart for a look although its probably had it if seized - I do wonder if the new cable has had something to do with the failure...

[Iain T]

JDO instrument just Refurbed and calibrated my tacho and cost £105.

Iain 

[Josef]

Cable driven ones are not really DIY repairable. Looking at £100+ for a professional repair. I have built my own electronic one for the Vitesse / Roundtail spitfire style but it’s not a super trivial thing to do (never seen someone offering a conversion as Colin mentions but I’d be interested to see it). What’s the ratio on the Vitesse one though? I do have spare cable driven inner workings I’m unlikely to ever need. 

[Pete Lewis]

cable driven ratio is 3.55 :1 

Pete

[Phil C]

Yes, a secondhand replacement is probably the answer although you never know what you are buying. I guess I can then have a go at fixing the original without worry.

28 minutes ago, johny said:

I do wonder if the new cable has had something to do with the failure...

Probably not, the car has been laid up in a shed since 1983 so may be I was expecting too much without giving it some attention?? The failure has occurred in the garage, not yet been on the road!

 

[Clive]

All the rev counters are teh same, 4 or 6 cylinder. So thay are not rare. 

Generally if you twist the rev counter and teh needle moves freely, it is OK. Or at least not seized.

[Iain T]

27 minutes ago, Josef said:

never seen someone offering a conversion as Colin mentions but I’d be interested to see it)

Josef, I think JDO offer an electronic upgrade. 

Iain 

[Phil C]

33 minutes ago, Iain T said:

JDO instrument just Refurbed and calibrated my tacho and cost £105.

 

5 minutes ago, Iain T said:

Josef, I think JDO offer an electronic upgrade. 

Just looked at their website, very interesting and I think I might give them a call tomorrow.

 

[Iain T]

23 minutes ago, Phil C said:

Just looked at their website, very interesting and I think I might give them a call tomorrow.

Very quick turnaround, they did my tacho in 4 days plus p&p. 

Speedy cables quoted 3-4 months! 

[johny]

2 hours ago, Phil C said:

Probably not, the car has been laid up in a shed since 1983 so may be I was expecting too much without giving it some attention?? The failure has occurred in the garage, not yet been on the road!

Its just that I wonder if the cable inner is slightly too long it can be jammed into the tacho drive connection as you do up the coupler so 'seizing' it...

[Josef]

11 hours ago, Iain T said:

Josef, I think JDO offer an electronic upgrade. 

Iain 

Oh right. I guess what I really want is to see how a professional company would do a conversion, and they’re unlikely to lend me one to take apart  My homemade conversion cost me about £50 in the end, and was based on a 90s Honda motorbike tacho. Finding a suitable donor that would fit well in the case and allow mounting of the Jaeger pointer and dial was the hardest part though. 

[Pete Lewis]

as with any cable drives the inner must engage the right amount  not too short not too long for all to work well and less flicky needled 

its surprisingly common  this is wrong ,its easy to solve  by grip the outer spiral wound case and screw/unscrew its casing 

this will make the inner drive effectively  longer or shorter   

Pete

[Colin Lindsay]

One repair service I just found on eBay:

https://www.ebay.co.uk/itm/372832224732?hash=item56ce8845dc:g:FVcAAOSwJeVdxCQ0&amdata=enc%3AAQAHAAAAoNiV90o04d0VZ6fF1Giznk7JyAbk1p240yoLFJCoQoNU3HSPVve6o0wzvIjnJiXsql6p5SH2seHZcIZ4uoGjNxCbni7upK%2BoaiC6q80NsotHCT2BpcOI4XlSoPHWGt3c02T3qiHu8CFzPVrYVTbrKleNgaulZvcvn6Mb%2B6IccreDSGi9SyrQKPfGhOVAkz84f8Ej06KIN13wDisdTtFulhI%3D|tkp%3ABk9SR5jQpZSKYQ

Found the conversion, too:

https://www.ebay.co.uk/itm/332585558254?hash=item4d6fa4e0ee:g:ug0AAOSwHMJYEeDU&amdata=enc%3AAQAHAAAAoJCzkcaQwh2aB%2FQ3D2fgX19pa2Qza%2FN3Eg47X139%2FO%2BkSOFPWKw%2F2%2Fc%2Bdq%2B9u90ZVHmf0ZmnnxyzkW9%2Bgczc1yfMzM%2F6qjnOxl0QvffihYURChQZ%2BmKgU6vYtGQWQYFTRK5tmYZNqKGyFshhkq6YnmQyuo0w0SO9rRh5%2FSzjmIf%2FH8hq2GkhgSOC3YNXthg9A%2F6Bn3VTgx5qwzYGRxaDf9k%3D|tkp%3ABk9SR5jQpZSKYQ

[Josef]

2 hours ago, Colin Lindsay said:

One repair service I just found on eBay:

https://www.ebay.co.uk/itm/372832224732?hash=item56ce8845dc:g:FVcAAOSwJeVdxCQ0&amdata=enc%3AAQAHAAAAoNiV90o04d0VZ6fF1Giznk7JyAbk1p240yoLFJCoQoNU3HSPVve6o0wzvIjnJiXsql6p5SH2seHZcIZ4uoGjNxCbni7upK%2BoaiC6q80NsotHCT2BpcOI4XlSoPHWGt3c02T3qiHu8CFzPVrYVTbrKleNgaulZvcvn6Mb%2B6IccreDSGi9SyrQKPfGhOVAkz84f8Ej06KIN13wDisdTtFulhI%3D|tkp%3ABk9SR5jQpZSKYQ

Found the conversion, too:

https://www.ebay.co.uk/itm/332585558254?hash=item4d6fa4e0ee:g:ug0AAOSwHMJYEeDU&amdata=enc%3AAQAHAAAAoJCzkcaQwh2aB%2FQ3D2fgX19pa2Qza%2FN3Eg47X139%2FO%2BkSOFPWKw%2F2%2Fc%2Bdq%2B9u90ZVHmf0ZmnnxyzkW9%2Bgczc1yfMzM%2F6qjnOxl0QvffihYURChQZ%2BmKgU6vYtGQWQYFTRK5tmYZNqKGyFshhkq6YnmQyuo0w0SO9rRh5%2FSzjmIf%2FH8hq2GkhgSOC3YNXthg9A%2F6Bn3VTgx5qwzYGRxaDf9k%3D|tkp%3ABk9SR5jQpZSKYQ

Those are just converting electronic types between different styles of operation (replacement circuit boards). Making a cable driven one into an electronic one needs a different movement, which is the tricky bit. 

[Colin Lindsay]

20 minutes ago, Josef said:

Those are just converting electronic types between different styles of operation (replacement circuit boards). Making a cable driven one into an electronic one needs a different movement, which is the tricky bit. 

Sorry, I had misremembered that they could also convert cable to electronic; but I've done that in the past too and I'm sure I remember a service advertised recently. Must keep looking!! In any case two originals on eBay at present, both £40 so might be the cheapest option.

 

[DanMi]

The tricky bit if converting to electronic is that the mechanical ones needle is heavy, I had one done professionally and it always slightly under read below 3000 and slightly over read above. I put it back to mechanical when I put the engine back to original so had a dizzy with the correct drive. I would just get a replacement mechanical 2nd hand.

[daverclasper]

9 hours ago, Pete Lewis said:

as with any cable drives the inner must engage the right amount  not too short not too long for all to work well and less flicky needled 

Mine flicky (intermittently) at idle only. Any idea if outer cable needs shortening, or lengthening?.

I did lube it ages ago, though, that made no difference 

[Pete Lewis]

at a guess i would wind the case to make the outer a little shorter and hence the inner a bit longer to make a better drive into the head 

but flicky needles can also  be a number of things .

Pete

[Iain T]

One cause of flickering needle is the spinning magnets. JDO who refurbished my tacho said that was the cause of mine reading too high. Not something I could sort out or calibrate. 

Iain 

[Phil C]

Thanks all for your input.

I agree the cheapest/easiest solution is the secondhand option. I had already fitted a new glass/bezel to mine so I can transfer this over to make the replacement all spangly 😎.

I still would like to understand the problem and will dismantle the seized one BUT only when I've secured a working replacement!

JDO can be the backup plan

The length of cable is very interesting and I will review this when reassembling. Need to replace the drive gear in the dizzy to fully assess this. My cable is new and sourced from Canley's so hopefully manufactured correctly??

Thanks again.

[Pete Lewis]

if you strip the dizzy drive take care withdrawing the welch plug as you need it to grip when refitting 

there is little to go wrong with the drive gears apart from lack of any lubrication 

and on that subject always an odd squirt of engine oil to lube the dizzy spindle top bush as its not engine lubricated and the shafts wears giving the points a wobble

some do say OIL  on the base plate and some have a felt oiler down under 

Pete