What is the correct operating temp?

[edpdx]

I installed the new Temp gauge. I got the part from the dealer some time ago; but did not install it until today.

The Temp gauge went smoother than expected. I had already installed the gauge in the dash alongside the ammeter/voltage meter. To complete the install, I cut a gasket to match the bolt-on bung for the new temp probe. When you do this, I recommend disconnecting the connector that comes from the firewall into the main harness right above the new temp gauge location. The bring all the wires forward as far as possible to allow wrench access. The stainless line- I think it's the one that runs off the back of the engine to the transmission modulator, is directly in the way- a gentle pulling and bending will move it enough for you to get the job done. You'll need a 9/16" Deep Socket, a gasket scraper and the new chevy part and gasket. The part numbers for both are elsewhere in this forum. Bung from GM, gasket from NAPA.

Question, where should the gauge read for temp? I drove for 10-15 minutes in 90 degree heat today, and the needle barely went to 140 °F. !?!

 

[Westech]

195 stat... but with a big radiator they will run cool untill a good load.

 

[boomer431]

When I installed my gauge it read 130 . After the truck cooled off I removed the sending unit and added coolant through the hole . Cranked it back up and read about 160 . It had an air pocket and was not toching the coolant.

 

[camogriz]

The HMMWV temperature gauge and sender I installed in my M1009 never goes above 160.

 

[hardcore]

I just installed my new mini gage in my dash it took a little bit of cutting on my back plate [I disabled my 4x4 light ] I know when I am in 4x4 but I put the mech. end in the water pump after I removed the plug I was not sure it was working rite but after reading your info I guess 140 to 160 is normal temp and it looks nice thanks for all your info guys

 

[cliffyp]

According to TM 9-2815-237-34 page 1-4, normal operating temp is 190-230. My temp gauge sits dead on 190. If the engine is under load for a while it will come up a bit, but falls back to 190 almost immediately as soon as its back to idle.

 

[cliffyp]

You should have a 190-195 thermostat, I forget which. Make sure your thermostat isn't stuck open

 

[rhinob]

Mine never goes to 190* unless loaded on a hill. It's ridiculous really. I'm sure my mileage is lower than it should be because of incomplete fuel burn.

 

[kenz5380]

I bet if your gauge never reads above 160 then someone along the way put a 160 degree thermostat in your truck. Mine sits at 190 just like it was described above and I believe that to be the stock configuration per the TM. I don't think there is any harm to running cooler except that your engine will be a little louder. I know in the Marines all of our HMMWVs had 225 degree thermostats. I always thought that this was a mistake on the manufacturers part as I attributed this to why so many of our engines had early failures, but that is just my opinion. I was told by one educated individual that he thought the manufacturer set them at 225 to make them quieter. If that is the case it is pretty silly in my opinion, but that info is purely anecdotal so you can take it for what it is. I don't know how the temp effects the power output but it has been my experience that cooler temps make for longer engine life. I would consider putting in a 160 degree thermostat if I needed mine replaced at some point.

 

[biggestc69]

I have an Autometer gauge and a 190 degree thermostat. I can watch the temp come up and its like the thermostat opens at 180 then drops to 170 and goes back up to 180 then back down to 170. Not sure if I have air in the system or what but this summer 100 degree temps outside pulling around 8000lbs never got over 190, thats with a new radiator too though. Winter time I run my Jatonka winter front and it helps hold the heat in alot! Really pleased with it. Without it it hardley hits 150 with it it does the 180 to 170 dance like "normal".

Kinda hard to see the water temp

 

[camogriz]

I wondered if the 160 degrees my M1009 registers all the time is too cold. I keep track of my fuel economy in an almost zealous manner and have never gotten better than about 15-16 mpg on a 200 mile roadtrip from NY to Rausch Creek Offroad Park for the semi-annual Rally. Around town is only 10-12 mpg. I wonder if I have a 160 degree thermostat installed that is causing the poor fuel economy. I would like to experience the 20 mpg I have seen quoted regularly on this site for CUCV's.

 

[kenz5380]

If you do change the thermostat out I would be very interested to know how it effects your economy. Please report back on how it ends up. I really hadn't considered the complete fuel burn effects of higher engine temperatures. I know that when the TMs are written for any vehicle there is more that goes into the recommendations in there than just what is the most efficient balance between wear and economy. Does anyone know what is really the most optimal operating temperature? I still hold by my opinion that 225 is way to hot, but it would seem that 160 is too low for efficient fuel burn. Is 190 or so the sweet spot?

 

[donalloy1]

I installed the new Temp gauge. I got the part from the dealer some time ago; but did not install it until today.

The Temp gauge went smoother than expected. I had already installed the gauge in the dash alongside the ammeter/voltage meter. To complete the install, I cut a gasket to match the bolt-on bung for the new temp probe. When you do this, I recommend disconnecting the connector that comes from the firewall into the main harness right above the new temp gauge location. The bring all the wires forward as far as possible to allow wrench access. The stainless line- I think it's the one that runs off the back of the engine to the transmission modulator, is directly in the way- a gentle pulling and bending will move it enough for you to get the job done. You'll need a 9/16" Deep Socket, a gasket scraper and the new chevy part and gasket. The part numbers for both are elsewhere in this forum. Bung from GM, gasket from NAPA.

Question, where should the gauge read for temp? I drove for 10-15 minutes in 90 degree heat today, and the needle barely went to 140 °F. !?!

Great job edpdx! Soon as I complete Tiny Tach install. This is my next upgrade mod. Thanks for paving the way SS's. DMLII sends respectfully

 

[donalloy1]

I have an Autometer gauge and a 190 degree thermostat. I can watch the temp come up and its like the thermostat opens at 180 then drops to 170 and goes back up to 180 then back down to 170. Not sure if I have air in the system or what but this summer 100 degree temps outside pulling around 8000lbs never got over 190, thats with a new radiator too though. Winter time I run my Jatonka winter front and it helps hold the heat in alot! Really pleased with it. Without it it hardley hits 150 with it it does the 180 to 170 dance like "normal".

Kinda hard to see the water tempView attachment 414350

biggestc69, I like your trio of gages! Looks clean and choices suite all my needs. Was it a comple kit or did you build custom? Please drop me a note. Thanks

 

[biggestc69]

Thanks donalloy1, its just a standard set of Autometer gauges with the three gauge holder. We chose that location because there really isnt a good place in a CUCV to mount gauges. We got some plastic wire looms and combined all the wires to make it look clean from the outside. And ran them through the front corner where the dash meets the windsheild. We had just enough room to pull it off, them pull your wires through and start hooking them up. The only thing that I dont like about the Autometer Trans temp gauge is that its electric. Its never let me down, but I'm a big fan of mechanical gauges and I looked and looked and could only find and electric to match the other gauges.

 

[donalloy1]

Thanks donalloy1, its just a standard set of Autometer gauges with the three gauge holder. We chose that location because there really isnt a good place in a CUCV to mount gauges. We got some plastic wire looms and combined all the wires to make it look clean from the outside. And ran them through the front corner where the dash meets the windsheild. We had just enough room to pull it off, them pull your wires through and start hooking them up. The only thing that I dont like about the Autometer Trans temp gauge is that its electric. Its never let me down, but I'm a big fan of mechanical gauges and I looked and looked and could only find and electric to match the other gauges.

biggestc69, thanks for reply! Trial and error in this camp to some extent. SS's help me avoid major blunders! This Thread is a great example of how benificial this site can be in my opinion.

Still not completly sure where I want my gages. Once Tiny Tach is done will find home(s) for Oil Pressure and Temperature Gages. A must for me! Drives me nuts not being able to monitor those. Idiot Gages are last ditch for me.


Respectfully DMLII sends

 

[allenhillview]

Gauges Autometer Mechanical

biggestc69, thanks for reply! Trial and error in this camp to some extent. SS's help me avoid major blunders! This Thread is a great example of how benificial this site can be in my opinion.

Still not completly sure where I want my gages. Once Tiny Tach is done will find home(s) for Oil Pressure and Temperature Gages. A must for me! Drives me nuts not being able to monitor those. Idiot Gages are last ditch for me.


Respectfully DMLII sends

You can take a look at this install. If you like PM me anytime
Also left all OEM gauges functional.

 

[biggestc69]

Allenhillview's install is ALOT cleaner than mine, lol. But then again so is his truck it looks like. We kinda though about running the gauges like he did but I wanted to be able to keep my head straight while driving down the road checking the vitals. Still looks alot better and cleaner than mine though. He put some work and time into it and it shows! Good job man!

 

[donalloy1]

You can take a look at this install. If you like PM me anytime
Also left all OEM gauges functional.

Very nice job allenhillview! Did you have fun with the plumbing? Looks very steril and functional. I also want to keep originals functional. Thanks for offering assistance. Really appreciate the thought. DMLII sends