HD5G Thermostat

The Detroit Diesel 2-71 in my Son-in-law's HD5G trackloader doesn't appear to have a thermostat ; I suspected this, but since I installed a new temperature gauge and SIL worked it hard enough that it should have been thoroughly warmed up, the gauge barely moves off the peg. It is nice to know that the cooling system isn't plugged up, but now we would like to get it to warm up properly.

What temperature rating would be best for this machine? We plan to do some digging and loading pit-run gravel as weather permits through the winter; the actual process will be to warm up the machine, load two small dump trucks, shut down and haul the gravel ~1/4 mile away, spread the gravel with another machine, come back, re-start the loader, repeat, etc.

Are there any "Gotcha's" that I should be aware of  before opening the system?

Thanks in advance

Ray54 wrote: Since nobody else will stick their neck out. I remember my HD5 running at 160 degrees, so guessing mine has 160 degree thermostat. But that's not from the book, or a real DD expert.

Thank you Ray

I did some google searching and came up with a range of 160-180 so I told SIL to get a 180 if available and no less than 160.

Looking at the service manual it appears to be pretty straightforward to R&R the thermostat, the hardest part will probably be removing the hood for access. Unless the t-stat cover bolts twist off