My 24 TT was positive ground when I got it. Is this correct? Also am considering an E-Timer as an alternative to pulling the engine, at least for now, to replace a dead mag. The ligature states that the E-Timer is for positive ground systems only. What would be involved in switching my TT from a positive ground system to a negative ground system?
NO - NO - NO...
re-read the instructions, (Please)
IMPORTANT! – The TipTop Timers E-Timer should only be installed on Negative
Ground Model T engines in good mechanical condition that run normally. The TipTop
Timers E-Timer will not fix engine problems due to carburetor issues, bad coils, incorrect
wiring or lose electrical connections.
Run your coils on 6V. Try it.
Reference to your statement:
the E-Timer is for positive ground systems only
If you have + ground now all that would need to be done is swap the battery cables, change the wires on the amp meter and flash the generator. If the cutout is the old style it does not care which ground is being used, if it's a new style, it would need to be changes to - ground type. (good idea anyway to change to new style)
I thought the E-Timer was only the one developed and sold by Mike Kossor, and that the Tip Top Timer was an Anderson flapper. Does Tip Top make both kinds?
As the Model T is a negative ground car, it would be odd for a timer to require positive ground.
Yes my mistake. I read the ligature correctly but when I made the post I got it backwards. I knew what I wanted but got it backwards. Thanks
Steve, I partnered with Tip Top Timers to make and distribute the E-Timer in their Anderson style housing while busy launching the Electronically Cranked Coil Tester (ECCT). That venture has since ended.
With a dead mag and no funds to pull and rebuild the engine (as in real life for many of us) I used a 12V battery on a separate circuit just for the coils. The rest of my TT is 6V.
Connect the 12v battery to the 'mag' side of the dash switch. 12V or more works better than 6V (mag puts out about 38V I think, so you could even run a 24v battery, but they are expensive to buy and a bit overkill).
Coils on 12v gives pretty close to the same performance as coils on mag. Just don't let a coil buzz continuously for a long time on 12 volts or it will overheat. In other words, it's fine to turn on the switch and crank and run on 12 volts. If something is wrong and it won't start, turn off the switch while you troubleshoot, don't just leave the coil buzzing.
On the Depot hack I just got, it has a 23v battery in it and some sort of resistor on the terminal block. Appeared that the 12v as for the starter and the lowered reistance wires went to lights and horn.
No mag working.
I was advised to try to get the Hack back to 6v as the starter jolting on a 12v battery was not good for the starter bendix spring, bendix and ring gear. Too much to quick.
So we got everything to 6v negative ground and all works well. We'll look at the mag when we pull the engine this winter.
If all A's are positive ground and all t's and tt's are negative ground, what would be a reason to convert a T or TT to positive ground? A circuit is a circuit, correct?
Just remember it is DIRECT CURRENT.. that means with a positive ground and negative hot... the starter will turn backwards...and so will the engine....
Also I don't expect it will run that way..
Starter turns the same direction regardless of polarity. Even if it did, turn backward, the bendix would never engage. Tell me you were kidding.
A series/parallel wound DC motor turns the same direction regardless of polarity.
There would be no reason to convert a T to positive ground unless some aftermarket accessory which used positive ground was installed. During the 1930s and 1940's many cars had positive ground. I know that Ford and Chrysler products had positive ground so if an accessory made for one of those cars had been installed on a T that would have been a reason to convert the T.
6 volt negative ground, properly rebuilt coils and a good clean timer will give you a real Ford Model T that will run great forever. Give it a try. Henry Ford and 15 million happy owners can't be wrong.
When the US military issues specifications for the design of the WWII jeep, they requested 6v negative ground system.
Must have been a reason for that.
Ground and bonding straps all over the place for radio static supression, but they still run today.
Some threads leave me speechless......
Guess it's just as well....