Speedometer pegs full scale back to zero as car moves forward. It goes back to zero as the car moves backward. The odometer works fine. I removed the speedometer & worked it by hand with same results.Is there a simple fix for this or do I need a new Speedometer. Also the tach reads nearly double the actual rpm.I folowed the instructions with the Pertronics ignition but I may have trimmed some off the + wire when I made the connection. Did this cause the problem or could it be something else?

68 E-Type 2+2

Submitted by pepe01@localnet.com on Fri, 03/30/2007 - 10:17

68 E-Type 2+2 Curtis,I tried Mo Ma & you are correct but they are not accepting any more new work at this time.I called Pertronics & they were very helpful.There can be a problem with Smiths instruments. The wire from the tach goes directly to the coil as does the + for the dist. They said to take the + dist. lead off & pick up a separate feed,leaving the lead from the tach on the coil.I'll try it once I get the engine back together. Paul

Submitted by georgejones123… on Sat, 03/24/2007 - 00:04

Paul,

On your clock I suggest you contact CoolCat at www.coolcatcorp.com or (914) 234-2083 They have an associate working with them who does electronic conversions on clocks and they still tick after the conversion.
I have had two converted and they work perfectly.

Good luck.

George

Private Restorer.66' 3.8 Mark 2, 67' Ser. 1 FHC "E"

Submitted by wcjssj@comcast.net on Fri, 03/23/2007 - 19:53

The cable does not drive the speedometer directly. It drives a magnet that induces eddy currents in an aluminum disc attached to the needle and that causes it to move. Your symptoms indicate to me that the magnet is touching the Al disc. This sometimes happens and can be repaired. I use Mo Ma (505-766-6661). While you are at it you might want to get them to repair your clock. At least for my MG, they put in a modern quartz works. Don't know about the tach. Have you called Pertronics? I have found them very helpful. 1967 E-type S1 FHC