Thermostart connections

TNford

Member
I have a 66 Ford 5000 SOS. The thermostart wasn?t/isn?t
hooked up when I bought it, but would really like to use it in
winter. There is nothing hooked up to it at all, neither the
electrical wire or fuel supply. Where do I connect for fuel? Can
I connect off the first injector? The manual talks about a
reservoir to connect to, but there isn?t one. How would I go
about wiring for it?
 

if you follow the return line from the injectors, to up the front of the fuel tank, there was a reservoir tee'd into the return line and then going back down to the thermostart. Later tractors did away with the reservoir, and just tee'd into the line, as the line itself contained enough fuel. Just remember the tee had to be low enough not to hit the top of the hood. And the normal return of fuel to the tank was keeping it supplied and full. The electrical lead should be in the wiring harness and is a heavy wire from the ignition switch to the thermostart. It required the BIG spade lug at the thermostart.
 
Agreeing totally. But I felt like adding how it works, if you are interested which will help you get the most out of it,and identify a TS
(Thermostart) module that isn't working.

Plumb and connect as Bill said.

Ignition switch will/may have a position between ON and START (my '65 3000 does) where the alt and oil lights go out....this is the TS
energizer position. Depending on the temperature, hold the key in that position for 30 seconds or more as the temp gets colder and then
roll on over to the START position where the lights are again illuminated and the engine rolls. When lit off and running, let off the key as
you do currently.

The TS contains a thermally activated plug that blocks the fuel and ignites the droplets of fuel. It glows red-orange when working. The
heat from this wire causes the plug to move away from the fuel line and let fuel droplets fall on the glowing wire which ignites them into
"Great Balls of Fire" (Jerry Lee Lewis popular song) that fall across the opening of the intake manifold.

As they fall, when you are in the START position, the engine is rolling and sucking air....the balls follow the air as glowing embers that last
long enough in the compression cycle to light off the diesel mist when injected. When you release the key, the ign switch returns to the ON
position, the power to the module is removed, the coil cools and the plug goes back into the fuel line and stops the slobbering.

Pull the intake air hose off the manifold and you can look in there and see all this happening; don't have to guess if it's working. If you
know you have fuel supplied....disconnecting the hose at the TS and watching it ooze out of the hose, and you know you have power at the
proper time...a voltmeter will determine that, and you don't see what I said, your TS device is inop and you need a new one. Easily
purchased, not that expensive...BTDT
 
Question on the wire...the wiring is cobbled together from previous owner, and there may not be a thermostart wire at ignition. Can I just use an alligator clip to positive post of battery to the spade connector and only use that when I want to cold start?
 
The original key switch for the '65-'75 thousand series diesels had the "off" position in the middle. "Run" was one click to the right and "Start was spring loaded to the right of "Run", and "heat was one click to the left of "Off", with a spring loaded "Heat-Start" position to the left of that. Most have since been replaced with ones that are as Texasmark1 described with "Off" all of the way to the left, and the "Heat" position between "Run" and "Start", partway through the spring loaded range of motion.
 
yes, but will need to be a heavy jumper as it would probably draw 10 amps... the factory wire was a 14 ga wire or maybe even a 12 ga iirc.
 
I have the thermostart but have never gotten around to hooking it up.
One of these days...
I have a large (heavy amp) momentary push button switch that I got off something else. Has the rubber cover so it's water resistant. I will hook it to the ignition switch where there's an extra spade connection, then run a heavy wire to this switch, then a wire to the thermostart. Mount the switch in the extra hole in the dash.
 

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