Does your Model T run erratically? It could be your timer that is at fault.
The timer is the Model T's equivalent of a distributor on a more modern car. Its'
job is to complete the ignition circuit down to earth for each cylinder in turn.
Simple enough you may think. The inner part of any timer is driven off of the end
of the camshaft and originally consisted of a roller that contacted with metal
segments within a cover to which the coil wiring was connected. This arrangement
allows for accurate timing but requires regular cleaning and lubrication to maintain
optimum running. Another inherent problem with this type of timer is wear. Dips
can appear in both the insulated section of the cover and also in the metal segments
themselves causing the sprung loaded roller to bounce which in turn leads to mis-firing.
Various types of timer have been tried over the years. In addition to the original roller
style (sometimes known as Tiger timers), there have been multi-roller, brush type (New Day)
and flapper style (Anderson). People have their own favourites but we have now tried
a few options and the T.W version has offered the best performance and the lowest maintenance
Ex-pat Englishman Tony Wiltshire comes from a race engineering background, having worked for Cosworth
engineering amongst others. Now located in Indianapolis, he has a CNC equipped workshop
enabling him to undertake projects of all manner. As a Model T owner, Tony has taken a
fresh look at the timer and come up with a fantastic solution. Starting with a housing that
looks almost identical to an original roller timer (but in fact produced totally from scratch)
Tony then installs newly made insulator and segments before the whole assembly is turned
to ensure everything runs true. He then CNC machines a self designed brush holder from
aluminium and installs a custom sprung loaded carbon brush.
We have been running a prototype version of the timer for over a year and 2000 plus miles
and we are confident enough in the reliability to be able to offer it for sale in the UK.
Tony has been kind enough to grant us the UK franchise and we are pleased to have a great
working relationship with him. The timer has proved to be reliable, consistent and low
maintenance in the time we have been running it, requiring nothing more than removal of
the cover from time to time to clean out any carbon dust that may have built up (probably
only once every 500 miles). No lubrication is required making this the cleanest solution
we have come across!
Brush wear is very low with a brush is expected to last around 5000 miles.
Of course, if your coils aren't up to scratch, you could still have an uneven idle and
poor performance so why not have them serviced and setup at the same time as fitting
the new timer?