Thermostart function and its components

Thank you. My ‘02 7.3 glow plug system is more complex, and of course computer (PCU) controlled by things such as oil temperature and then controls activation and time out of the GPR from the PCU through the ground wire of the coil side, and and different time intervals .

I have a LED indicator lamp wired to the GPR glow plug terminal. You would be surprised how many people who own those still don’t fully understand the glow plug system, especially when they talk about cycling the key several times because the (WTS) wait to start light has gone out. (Two completely different, and written programs in the PCM that are not remotely related.

With the 4000’s there’s no PCU, very basic, and I appreciate the advice on the oil bath.. I plan to start with short durations, using caution as I increase the length of time it’s activated with the given ambient temperatures.
 
Thanks for the reply. From what I’ve read it’s been recommended to hold the TS engaged for 30 seconds before cranking.

During that time (30seconds) is my concern. I drilled and tapped a 1/8” npt to install a temperature probe, in cleaning out the shavings with a small vacuum hose is when I discovered how oily (greasy) thr intake is. Here’s a picture that might better explain my concern.


After Dilling
View attachment 132600

After vacuuming shavings…..light shining through hole from troublelight.
View attachment 132602

If I decide the risk for fire is too great I will simply remove EGT probe and install a 1/8” npt plug.

View attachment 132605

I noticed the greasy mess when sliding the vacuum tubing in and removing. During a search I found several threads where an OP reported similar buildup and the consensus was for an older diesel with lots of hours, Thats it wasn’t uncommon.

Just not sure about starting a fire inside🫤
the 5000 has an oil bath air filter.. and when working in a very rough field, it will occasionally splash some oil up, and into the intake. It will also splash and spill a bit of oil on the radiator, partially clogging it with dirt.. Later models changed to a paper filter to stop both problems... And yes the thermostart will light up and create "great balls of fire" getting sucked into the engine while cranking......well little bits of fire. After a couple of thermostart cycles, the manifold will no longer be wet. The whole point is the heat the the air in the manifold up to 400 degrees on a cold start. so yes, its design for a small flame. The oil bath air filter will keep the flame under control if its filled up correctly.
 
IIRC, the earlier 4 cylinder diesels did not ignite any fuel in the manifold.
They merely heated the air in the air cleaner. I doubt it was as effective as the thermostart on the 3 cyl models but never had to use it to find out.
I only watched it on my 1965 3 cyl, not on my 4 cyls.
 
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IIRC, the earlier 4 cylinder diesels did not ignite any fuel in the manifold.
They merely heated the air in the air cleaner. I doubt it was as effective as the thermostart on the 3 cyl models but never had to use it to find out.
My superdexta had a diesel line going to the manifold heater, with a manual valve cock on it. I dont know if it was added or not. And not sure how it functioned as I never turned the valve on as far as I can remember. It looked like it was added after the fact though. That was a 3 cyl perkens iirc. Was a super great tractor other than no power steering..
 
My superdexta had a diesel line going to the manifold heater, with a manual valve cock on it. I dont know if it was added or not. And not sure how it functioned as I never turned the valve on as far as I can remember. It looked like it was added after the fact though. That was a 3 cyl perkens iirc. Was a super great tractor other than no power steering..
I had 2 MF 35s, one gasser with PS, and one with a perie 3 banger without. I really liked the tractor and its pulling power but I sold it because it had no PS. I sold the one with PS too because it was a gasser.
 
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