CUNO TIMER

The Ubiquitous


| March/April 2000



Parts of the Timer

Figure C

40021 Ben Morgan Road, Leonardtown, Maryland 20650-2521, Copyright Retained.

One of the most, if not the most, popular marine engine timers was made by Cuno of Meriden, Connecticut. I have not been able to determine the production life span, but it does appear it began about WWI and came to an end about the beginning of WWII. This simple but reliable timer was used by a large number of engine makers on one through four cylinder marine engines. The Cuno timer was also often used as a replacement timer for marine engines that had faulty or unreliable timers. See Figures A and B.

The Cuno timer is really very simple once one understands how it is assembled. It is also apparent that a lot of marine engine buffs don't understand how it is supposed to be assembled. Hopefully this article will be of help to those having Cuno timer problems.

The Cuno timer has four principal external parts:

(1) The timer case with handle that contains the lower (angular contact) ball bearing and an internal fiber ring mounting one to four contact segments which are insulated from the case. The contact segments would be connected to individual spark coils. (One coil per cylinder.) See Figure C 'A.'

(2)The cover containing the upper (angular contact) ball bearing. See Figure C 'F.'