Wigl4me
New member
Hi guys. I wanted to post this because I've seen other people ask about it or comment on it but never really answer the question in depth. It pertains to the thermo start system on older ford TLB tractors and wiring to a new ignition switch. With original ignition switches, to use the thermo start you'd actually turn the key COUNTER CLOCKWISE once to "heat", and then farther COUNTER CLOCKWISE to "heat/start". The new ignition switches are different. Everything is done CLOCKWISE. So let's say you put the key in the ignition..that's step 0, turn it one click CLOCKWISE. (This energizes accessory by connecting lug 1 which is BATTERY 12volts to lug 2, accessory) this is step 1. Now turn it one more click CLOCKWISE. (This energizes ignition and accessory by connecting lug 1 to lug 2 and lug 4) This is step 2. Now this next step is where people get confused. There are no more clicks left on the ignition switch. From here forward you turn it clockwise and it springs back. However...there are actually two parts to the spring action. If you turn it just a little bit it energizes the Thermo start pre heat. This is lug 3 on the back of the switch. We'll call this step 3. Hold it there for 25-30 seconds. Now turn it a little farther and this energizes both lug 3 and 5 which is pre heat and heat/start. This is step 4. These switches are made to work on both gasoline and diesel engines so they have 5 lugs on the back instead of 4. If you have a diesel engine, theres no need to use the "ignition" lug (4)and if you have a gas engine, theres no need to use the "pre heat" lug (3) I hope this helps someone down the road. : )
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