Hey - did you know if you click on the title of a thread it will take you to the first unread post since you last visited that thread?
but were afraid to ask: 
STOP!! Never post your email address in open forums. Bots can "harvest" your email! If you must share your email use a Private Message or use the 
smilie in place of the real @
Pretty Please - add it to our Events forum(s) and add to the calendar! >> 
KeithViolet
Freshman Member
Offline
1991 XJS when the car is cold the tach won`t move until I tap the dash. Is the repairable? Lubrication or something and is it easy to do ?
-
Hi Guest!
You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
There are some perks with a member upgrade!**Upgrade Now**
(PS: Subscribers don't see this gawd-aweful banner
Tach Problem
- Thread starter KeithViolet
- Start date
Share this page
Healey 100
Jedi Warrior
Offline
I don't know the answer, but the '69 E-type I am working on does the same thing. Only it fails hot or cold. But a tap on the instrument usually gets it going again.
It acts like a bad ground or something. I did check the wires on it, and all are secure.
I'm hoping to hear of a simple fix before I try to remove and replace the thing.
Bill.
It acts like a bad ground or something. I did check the wires on it, and all are secure.
I'm hoping to hear of a simple fix before I try to remove and replace the thing.
Bill.
Offline
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Basil:
I suspect its just dirty and needs cleaning.
Basil<hr></blockquote>
Carefully - like a clock.
D
I suspect its just dirty and needs cleaning.
Basil<hr></blockquote>
Carefully - like a clock.
D
Offline
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Dave Russell:
Carefully - like a clock.
D<hr></blockquote>
Actually, when I get ready to do my Jag Tach and Speedo, I am sending them to
Nisonger's for refurbishing. I wouldn't dare try to pull them apart myself.
Basil
Carefully - like a clock.
D<hr></blockquote>
Actually, when I get ready to do my Jag Tach and Speedo, I am sending them to
Nisonger's for refurbishing. I wouldn't dare try to pull them apart myself.
Basil
Michael J.
Jedi Warrior
Offline
Check the condition of the instrument cluster wiring connector where it plugs into the panel. the connector contacts or the female contacts in The panel connector contacts may have tarnish or corrosion that interfers with the signal. As the contacts heat up because of the tarnish, the resistance lowers and the signal would then be near normal. Clean the contacts with some steel wool.
Make sure that the battery is disconnected first so as not to fry anything.
Make sure that the battery is disconnected first so as not to fry anything.
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>or the female contacts <hr></blockquote>
hmmmmmmmm
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>ay have tarnish or corrosion that interfers with the signal. As the contacts heat up because of the tarnish, the resistance lowers and the signal would then be near normal. Clean the contacts with some steel wool. <hr></blockquote>
....ok...I was already daydreaming...thanks for waking me up...
Danny
hmmmmmmmm
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>ay have tarnish or corrosion that interfers with the signal. As the contacts heat up because of the tarnish, the resistance lowers and the signal would then be near normal. Clean the contacts with some steel wool. <hr></blockquote>
....ok...I was already daydreaming...thanks for waking me up...
Danny
Healey 100
Jedi Warrior
Offline
FYI, I finally removed my tach and took it to a local instrument shop. They said it had a bad ground on the internal circuit board that they were able to fix.
It seems to work OK now, time will tell if this fix is permanent.
Question: does anyone know if electronic ignition setups (like Pertronix) will affect these electronic tachs?
It seems to work OK now, time will tell if this fix is permanent.
Question: does anyone know if electronic ignition setups (like Pertronix) will affect these electronic tachs?
John S Farrington
Jedi Warrior
Offline
Pertronic and Crane/Allison ignition ignition kits will not interfere with the tachs that this topic discusses. There can be problems with E Type tachs that have a positive signal drive but the tachs can be rewired. The XJ tachs have no problems with the Pertronic.
Offline
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Healey 100:
But a tap on the instrument usually gets it going again.
snip
I'm hoping to hear of a simple fix before I try to remove and replace the thing.
Bill.<hr></blockquote>
I think that Jag had a special tool - "rubber tach tapping hammer" which might still be available.
But a tap on the instrument usually gets it going again.
snip
I'm hoping to hear of a simple fix before I try to remove and replace the thing.
Bill.<hr></blockquote>
I think that Jag had a special tool - "rubber tach tapping hammer" which might still be available.
Bob Stevenson
Senior Member
Offline
I don't know why the type of ignition system would effect a S1 E-Type as the tach is not connected to the ignition circuit.
John S Farrington
Jedi Warrior
Offline
Bob Stevenson, The tachometer arrangement I was refering to is a series 2 that uses the 12 volts to the coil primary circuit through the tach signal to get the drive. You are right in that the series 1 uses a sseparate transduder on the back of the cam drive. The positive drive on the series 2 is a little flakey with a Pektronic.