Rods 'n' Sods - UK Hot Rod & Street Rod Forums banner

1 - 8 of 8 Posts

·
Off the Xmas card list
Joined
·
24,128 Posts
Discussion Starter · #1 ·
What would make a tacho surge ? I've fited an electronic dizzy, ticks over fine, no misfires etc but the tacho will remain steady and then either when depressing the throttle or juss by itself the needle will surge upwards before dropping back ? Downwards I could understand as a loss of power / lose connection but upwards ?
 

·
Off the Xmas card list
Joined
·
24,128 Posts
Discussion Starter · #3 ·
Yes, as per the contacts dizzy .I've just swapped back to the points and the surge is gone ?
 

·
Registered
Joined
·
1,267 Posts
It sounds like the rev counter is picking up a back feed from the electronic ignition somehow.

I've seen hall effect electronic ignition send odd signals before but not enough to power a rev counter like yours has???
 

·
Off the Xmas card list
Joined
·
24,128 Posts
Discussion Starter · #6 · (Edited)
Found it !! It's Bosch unit with 4 downward hanging tangs and when I was checking the bearings noticed that 1 was at a (very) slightly different angle. I adjusted the air gap on the straight ones and confirmed that was the problem. Straightened it up and refitted ..purrfick
 

·
Exceeded sell by date
Joined
·
7,742 Posts
Interesting. During the problems with my ignition my tacho would shoot up Kev.
Finally switched over to MSD yesterday(I know Johnny will not approve!) and all is well with the world.
 
1 - 8 of 8 Posts
Top