Thermostart (Glow Plug) for a Farmtrac 545

[robertmeyer524]

If you are attempting to replace the Glow Plug (thermostart) on a
FarmTrac 545 the following works. The new threads I cut were about
.007" smaller than the original glow plug, but it was easier to cut
the glow plug than it would have been to tap out the intake to 7/8-14.
I ordered two of these glow plugs on amazon for less than $40. The
tap and die was less than $30. Once snow flies next winter we will
see if the repair will provide a diesel that starts. Since I was
already working on the electrical system I added a momentary push
button switch for the thermostart circuit and added a relay that
mounts in the battery tray. The original switch applies voltage to
the thermostart via a 10 gauge wire everytime you hit the starter.
The idea is that you use the transmission disconnect switch to disable
the starter, and hold the switch in start to energize the thermostart
(glow plug) for 20 secs, then take the tractor out of gear and crank
the engine. Who thought that idea up was trying to save money at
manufacture. Using a relay and a smaller gauge wire for control is a
concept that has been around since the early 1900's.


1- Order a 2666108 Glow Plug for a Ford Tractor - it arrives with a

7/8-14 Thread.

2- Order a 13/16 -14 Tap and Die

3- Cut the New Glow Plug (Thermostart) down to 13/16-14 Thread

4- Add an O-Ring, Teflon Tape if needed and Install it into the FarmTrac 545 intake

 

[rrlund]

I've got one on my Fiat built Oliver 1365. On that one, you turn the switch clockwise to activate the thermostat, then farther to activate the starter while the thermostat stays on. You turn it counter clockwise to activate the starter only. Make sure you bleed that out right. I put a new one on mine and burned it up. Hold it for 15-20 seconds, turn it off so it cools down a little, hold it again and do that until you have the line bled so there's good fuel flow to it.

 

[robertmeyer524]

I've got one on my Fiat built Oliver 1365. On that one, you turn the switch clockwise to activate the thermostat, then farther to activate the starter while the thermostat stays on. You turn it counter clockwise to activate the starter only. Make sure you bleed that out right. I put a new one on mine and burned it up. Hold it for 15-20 seconds, turn it off so it cools down a little, hold it again and do that until you have the line bled so there's good fuel flow to it.

Good idea on bleeding the system. This has a fuel return line to the fuel tank where it "T's Off" and then gravity feeds to the thermostarter. The thermostart does not appear to have a control valve of any kind so I assume it feeds a small amount of fuel into the intake all the time. ???

 

[Powered By IH]

The thermostart does not appear to have a control valve of any kind so I assume it feeds a small amount of fuel into the intake all the time. ???

No, the thermostart has a valve inside it so when it heats up, it opens, and when it cools back down, it closes that valve.

 

[robertmeyer524]

The fuel line feeding the thermostart was also too large for the thermostart, so I had to drill it out as well. It was only off by a small amount. Using the correct size of drill bit only reamed out the hole a few thousanths of an inch.