7 replies to this topic

[BeardySimon]

Just fitted a jaeger rev counter........

Whilst it is  the connected to the coil, the car just won't start. I replaced points, condensor and checked plug gaps. Unplug the tacho, and it starts just fine!

Thinking I need to upgarde my standard old coil to a sports?

Anyone had this problem before?

Regards!

 

 

[jaydee]

RVC gauge?

[BeardySimon]

Ta for reply. RVC? No idea! It turns over but wont start so was thinking need a better spark?

[jaydee]

Noi it may be a problem with the rev counter if its the RVC type

[KernowCooper]

Looks like the coil with the rev counter wired is not triggering, what rev counter is it ? or whats it out off ?

 

Don't waste any money upgrading the coil it wont solve the problem, as the primary winding has to be triggered the same as you existing coil to work,

 

What wires/connections do you have on the rev counter

 

Thinking back there were two types of Jaegar the one with a tie up with smiths and the French ones which if I remember correctly had electronique on the rev counter face, and they being that type most were the type that wired up the same as a RVI we had in which case it would need to be modified to work on a single wire to the coil,

 

Before we run away with what it might be maybe a bit more info and a photo fron/rear would help.

Edited by KernowCooper, 24 October 2013 - 10:47 PM.

[dklawson]

There is Jaeger and British Jaeger.  Jaeger (without "British") is from the continent.  I have not seen much information on how to wire them.  Gauges marked British Jaeger were made by Smiths and are typically an older design.  

 

On the gauge face, look for the following:

"Earth".  Make sure you have the correct for your car (Positive or Negative) with most cars after the 1960s using "Negative".

Also look for the letters RVC or RVI.

 

RVI tachs are older/earlier.  They wire in series with coil power and do not work properly (generally) with electronic ignitions.  They are NOT like modern tachs and they are not wired to the car in the way modern tachs are connected.

RVC tach are later, use a single wire hook-up to coil (-) and (generally) do work with electronic ignitions.

 

If your tach is an RVI type, only consider using it if your car has points.  Do not waste your time if the car has an electronic ignition.  If you have a car with points and want to use this tach, post back and we will add wiring instructions for it.

If your tach is a later RVC type, it will work with virtually any ignition.  The tach uses spade lug terminals to connect power and uses a single sense wire from a bullet connector to coil (-).  The case is typically earthed.  

 

Post back with which type of tach you have and how you have wired it.  Based on your statement that this is a Jaeger tach and that the car won't start once the gauge was fitted, I suspect that you have an RVI tach and that you have connected a single wire to the coil and a second wire directly to earth.  That wiring creates a very effective kill switch. 

[BeardySimon]

 photo 1.JPG   68.91K   13 downloads  photo 2.JPG   69.29K   20 downloads

 

Thanks for the informative replies!

 

Hope you can see the photos. I have one wire to permanent live (red), one to earth (blue) and one to (-) coil (purple). (ignoring the illumination).

Just to confirm, that as is, when the engine is running and I connect to the wire to the coil, the rev counter works but engine will then run very rough.

It is french. My ignition is NOT electronic.

Many thanks.

[dklawson]

You are correct, the tach you have is French, not "British Jaeger".  I will look to see if I still have my notes on how they wire up.  They are not like Smiths instruments.

 

Regardless, what I can tell you based on the original symptoms is that the wire going between coil (-) and the tach is being held "low" all the time and that is preventing the engine from starting.  That could be a wiring error or an indication that the tach has problems.

 

EDIT:  Going through my printed records I found my information on French Jaeger tachs came from the link below.  Please see it and use Google translate as necessary to make sense of it.

http://philippe.bour...fr/pdgindic.htm

 

Look carefully at the text and pictures at the bottom of the page.  I don't speak or read French but the left most pictures at the bottom of the page says that there should be a terminal on the back of your gauge that is insulated from the case and that the wire to coil (-) goes there.  However, there should also be an insulated terminal for connecting +12V to the gauge and that is not shown (it is suggested in the two right hand pictures at the bottom of the page and MUST be there to power the gauge).  The terminal that is in direct contact with the gauge case without an insulator should be the earth connection.  

 

I cannot tell from your picture which terminals are insulated from the case.  My suggestion is to make sure that the earth connection is to the terminal in direct contact with the gauge case.  Then try connecting the +12V and coil(-) wires to the two insulated terminals in both orientations.  If the engine will not start with the power and coil wires connected in either configuration I would consider this tach a lost cause.

 

EDIT(2):  Of course... if you know the vehicle where this French tach was originally used you could look for a wiring diagram for it and hopefully identify the connections.

Edited by dklawson, 02 November 2013 - 01:47 PM.