? For those with coolant temp gauges

[Haoleb]

Just finished installing a mechanical oil pressure gauge and an electrical coolant temp gauge on my M1028A2. The oil pressure gauge works great. I ran Stainless flex line to a bulkhead fitting in the firewall and then ran some heavy duty parker nylon tube to the gauge inside the cab...

The coolant temp sender I was originally going to install in the plugged port on the water pump but then decided to remove the glow plug module temp sender located the the drivers side rear of the engine and install my sender there. Two reasons... One I did not need that sensor anymore because my GP module is gone and operation is completely manual and also ended up just cutting and capping the wires because the connector was frayed anway. So I installed the new temp sender in that location.

The issue I seem to be having. (maybe it is not an issue?) is that it does not seem like it gets very hot there. I started the truck up and let it warm up 5 mins or so. Never went above 100 degrees. So I took it for a quick drive maybe a few miles and it only ever got up to about 130ish for temp in that location. I physically felt the sender and the block in that area and indeed it was not really hot.

My question is.. Has anyone else installed a real temperature gauge with the sender in this location with success before? Or should I move it to the water pump instead? I have a practically new cooling system new radiator water pump t stat etc.. When I took the old sender out I thought coolant would come spilling out and that was not the case. There was coolant in there but not until I squeezed a radiator hose did it come out of the hole. When I first finished the cooling system repairs I did think it took forever for the tstat to finally open. Maybe 10 minutes or idling if not even longer. Seems like this engine does not get hot quickly?

Should I just leave the temp sender in its current location and just get used to what a normal temp is and then I will know if it gets hot? I am used to an engine running around 210. I did not drive a long time but as I said it never got to even 150.

 

[richingalveston]

get an IR thermometer, it is great for checking temps of everything on the truck. They are not expensive.
I keep one on my truck and when I stop I check t-case, wheel hubs, brake rotors radiator, oil pan.

knowing all the regular temps helps to identify problems early. I walk the truck anyway and check it for safety, tires, lugs, having the temp of everything gives you so much more info to what is happening with your ride.

back to subject, use it to check the areas of the block, you may have bad flow in that area. It may take a long time to heat up but also take a long time to cool. you are better off with it at the water pump.

 

[Tinstar]

Move it to the water pump.
While not as accurate as one would be in the crossover pipe, it will give a better and quicker reading than that port.

Mine me is at the water pump and does great. You can see the thermostat open.

 

[blueblaze]

I have mine in the same spot on the pass side of the head. I installed another ported plate and put my temp sensor in. Normal driving I read 140 to 150. After a long highway haul or a hotter day. hot being more than 25 Celsius It'll be around 180 and Ive seen it go all the way up to 220 going up hill with my foot in it on a hot day. Some say its not as accurate while other diehard 6.5 and 6.2 guys love that spot because that's where the overheating issue transpired around the no.8 cylinder.

 

[Drock]

Unfortunately the only place to get a truly accurate overall reading is to mount your sensor just behind the thermostat. And that requires a HMMWV coolant crossover swap. They can be had on Ebay for around $50.00

 

[Haoleb]

Thanks for all of the suggestions. Now I am torn if I should move it or not. Good points on both sides. I guess I will run it as is for a few days and take it on some longer drives and see how it works. If the gauge never really creeps up much I will probably move it to the water pump. I don't do any heavy hauling or towing but it is nice to have the gauge to see what is going on. When I first installed it and took it out I thought for sure the darned thing was not even working at all or there was some sort of cooling system issue.

 

[Tinstar]

At least with the water pump location you have more flow over sensor.

 

[Sharecropper]

I could be wrong, but I believe the water pump location will not provide accurate temperature readings because the water will have just arrived from the radiator and therefore will be cooler than the water after traversing through the engine. If anyone knows this for sure please chime in. I am preparing to install a gauge myself and I plan to obtain the temperature reading from the rear of the passenger side head.

Hope this helps.

 

[Haoleb]

I could be wrong, but I believe the water pump location will not provide accurate temperature readings because the water will have just arrived from the radiator and therefore will be cooler than the water after traversing through the engine. If anyone knows this for sure please chime in. I am preparing to install a gauge myself and I plan to obtain the temperature reading from the rear of the passenger side head.

Hope this helps.

That was my though too which is why I ended up not putting it in the back of the block. Then I thought about putting a tee fitting onto the heater core hose nipple from the crossover pipe but without taking the hose off it appears to be some sort of special bent hose fitting with no room for a tee.

 

[Tinstar]

I could be wrong, but I believe the water pump location will not provide accurate temperature readings because the water will have just arrived from the radiator and therefore will be cooler than the water after traversing through the engine. If anyone knows this for sure please chime in. I am preparing to install a gauge myself and I plan to obtain the temperature reading from the rear of the passenger side head.

Hope this helps.

correct.

I have a brand new HMMWV crossover pipe. Just waiting to install for something else that I can replace. A lot of work for just the temp sender location.
Drove 1008 several days above 100 outside.
Never passed 190 and trans never passed 200.
Will have sensor installed in new crossover this fall.

 

[Drock]

Before doing the crossover swap I had my sensor mounted in the water pump and it would never read higher then 160°. Now it reads 190° to 210° depending on how much work I'm putting through.