Hi,

I was just out for a drive today when I looked down and the tach has stopped working.

Unscrewed the cable off my original points dissy when I got home and sure enough, it's broken about 2 inches along the cable.

Are these a PITA to fit a new one ??

Or -
Do you think I should retro fit some sort of electronic distributor & tacho ?
Go aftermarket cable HEI dissy ?
Just buy a new cable and wait another 43 years for it to fail ?

I'm sure this has happened to many a forum member.

It's a 68 SB.

Cheers, Luke.



Cheers, Luke.

 

If the problem is only the cable, it is an easy fix. But, before installing a new one, you need to pull the tach driven gear gizmo out of the dizzy and check its condition. There is a worm gear built onto the tach drive shaft and that brass cable connector should just 'screw' out of the housing so you can take a look at it. Check condition of worm and driven gear; also see if there are brass shavings in there that would indicate some damage to the driven gear (the worm gear on the shaft is hardened steel and should be OK in any event). The end of that driven gear may have dug into the inside of the dizzy case, also. That would need to be repaired so that the running clearance for that gear set will be maintained.

If you find a lot of shavings in there, it would be best to remove the dist. and disassemble to clean, check thoroughly, and do any needed repairs before reassembly. All those parts are replaceable and available.

If you find no shavings, stick a blob of white lithium grease on the tach driven gear, reassemble to the tach body, and hook up a new cable. It should be fine....unless there is some [odd] binding problem in the tach gauge, itself. You can always hook the new cable up to the tach head first and turn the cable with your fingers to see if any binding is present, before you hook it up to the distributor.

 

Happy motoring for the next 4 decades.

 

Hi Luke,
Since you mention it broke about 2" in/along it's length, you might want to check the position of the distributor to see if in setting the timing, it's been turned so far as to put a 'kink' in the cable near the distributor.
Checking that might prevent the cable problem from occuring again.
Good Luck!
Regards,
Alan

 

You may need to re-clock the distributor to get a straighter run on the cable (if you can make adequate distributor movement to adjust the timing) or install a right-angle cable adapter. Too tight a bend is bad for cable life.

 

Why?

Why?

Bingo.

 

Thanks for your help/comments guys.

I might just grab another cable and replace it.
As Alan suggested, I should turn the dissy around a bit more as it does have a nasty curve in the cable.

Maybe the old points dissy can keep on going for a while longer yet.

Off to Willcox for a new cable...

Cheers, Luke.