coolant temps

[punkmechanic]

There have been a few threads the last couple weeks concerning coolant quality and cooling system efficiency. Namely the problems caused by one or both being subpar.

I think we need to establish a "baseline" of what is what on the coolant test strips, where to get what coolant and additives, and what makes a coolant system sufficient or less than adequate.

I for one have two temp gauges in the truck and dont know which one to follow. I have the stock one that gets its reading from the front of the block and a second isspro plumbed into the rear of the drivers side head. My stock gauge ( I know they are less than ideal, but mine still works) stays in the safe range (to me that is from midway to low, correct me if Im wrong, thats why I started this post). The isspro on the other hand spikes everytime I pull a grade. It usually stays below 230 but has gone as high as 250. If I see it hit 230 and continue climbing I pull over and let it cool off. My sig states what all is in the truck (hypermax, unknown quality pump, newer injectors, pump is up two flats, running 50/50 transdiesel, and I think my cooling system is plugged up.

When I bought the truck a year ago it had been sorely neglected. I have fixed what I have found and this is really bothering me (especially in light of the recent head cracks listed by another member).

What temps should the engine see and at what times. The cylinder head temps are going to the hottest of the engine and fluctuate the most (hence the reasoning for a gauge in the head).

does anyone else have a cylinder head temp gauge and if so what are you seeing for numbers? I really want to know what is up. I have the data but nothing to compare it too.

punk

 

[dakotajeep]

Good call. I am curious also. I was really worried when pulling a loaded trailer and the stock guage started going to the L......I got worried that I might I screwed something up.

More info would be good.

Thad

 

[punkmechanic]

with the ways things are going (the economy, lack of knowledge on these older rigs, tighter emissions, etc) I think we need to start systematically getting all the known issues and info on these trucks. This will help "newbies" to this site to keep these things on the road. I for one am astounded that I didnt get one sooner and now am looking to fill a storage area with all the pieces I could conceivably need. With the ih plant going under and the aftermarket not supporting us, we need to team up or slowly watch the idi's go away.

punk

 

[typ4]

Get a big storage area punk, I got stuff to put in there
Brandon might have some stuff too.

 

[icanfixall]

Actually the best location is the stock location... Why you may ask... This is the transision location where both flows from the heads and block joins up before it sees the thermostat. Now if you use the front of the heads then your temp will be around 7 to 10 degrees higher than the stock location.

 

[fastass350]

I too have two guages, the stock one, and an auto meter electric plumbed to the rear lower side of the drivers head. It's been accurate every time I've checked it with one of them laser thermometer deals. Mine always runs 200-210, even when pulling a hill, loaded or empty. When mine sees 250 (which it did recently) I find that's when the heads get cracked. I never have liked much more than 220, and get very uncomfortable around 250, but that's just me.

 

[punkmechanic]

thats why I started this thread. we know the heads crack when they "get to hot" but what exactly is too hot and at what location is the too hot temp being measured. Im concerned about the 240* on my cylinder head gauge but that could actually be normal and Im worrying over nothing. I have been told my cooling system is sub par but I havent seen too many trucks with much better than mine and I have seen a lot with way worse, and no ill effects on either.

just trying to get some info on a less than normal issue I guess.

 

[fastass350]

What do you mean by sub par? Is there issues with things not flowing or not working?

So do I understand correctly, that taking a temp reading where ours are placed (in the rear of the heads) will read warmer than other areas, so it's somewhat false? I don't know much about stuff like that

 

[typ4]

His cooling system is rust colored and needs a good flushing. Looks like red barn paint.

 

[Diesile]

I like the idea behind this thread, a place to register collective information from all of us concerning our idi's cooling system. The folks with two (or more!) gauges running from different locations is instructive if those gauges with their respective senders have been run from a single spot (pan on the stove?) first to verify any difference.
My 6.9 and factory turbo 7.3 both have never gone over 205 at the stock location with a Stewart Warner (sp?) mechanical gauge. That includes 50 degree days with the 9' Fisher plow blocking most motion generated flow thru the radiator. I believe the system is in good shape with a 3 year old replacement radiator and anti freeze.

 

[69dieselfreak]

arizona heat (100+) pulling a long steep grade with a loaded trailer (ford f250) in the heat of a summer day i got all the way up to 230 i backed off a bit but i was able to finish climing the hill with out stopping
summer time and winter normal driving conditions 190
what im running in my truck is in my sig
punk
it just sounds like you need a good flush and if that doesnt work then you might have to have you radiator rotted out

 

[punkmechanic]

I have flushed it more times than I care to count. the coolant is fresh and stays green with no build up. I think it may be that the radiator needs rodded out. I have looked at similar trucks at work and their cooling systems look to be in the same or worse shape than mine and they have no cooling issues. the water-pump and thermostat are newer (put in 8k miles and 7 months ago).

punk

 

[Captain Morgan]

punk,

my recommendation is 180min to 210max for operating range with no more than than
230 before cool down. Your cooling system might be ok, maybe you aren't flowing enough air for the amount of fuel you are running (overfueling)? I am just thinking out loud here.

If you are sure it is in the cooling system and you have replaced the waterpump recently, did you replace the thermostat and radiator cap while you were at it?

Have you checked cooling system pressure?

I haven't touched a 6.9 in years, but remember well when we had to keep them in service. just food for thought.

 

[punkmechanic]

I bought the truck in january of 08. It was a mess to say the least. after rewiring the back half to get tail lights, putting in a new vacuum pump, and replacing the fuel filter I drove it 120 miles home. Over the next two weeks I stripped and cleaned the interior (literally a 5 gallon bucket full of sand, dirt and dog hair ), rattle canned it black and started driving it daily.

I drove it till april and noticed it liked to get hot (this was in florida where the asphalt gets to 140+) pulled the cap and found rusty liquid. Bought flush, cap and hoses. Flushed till clear, filled with new coolant and dca4 after installing the cap and hoses. That lasted till may when the waterpump started leaking. Replaced the lower hose again (had a pinhole in it from the parts store hang up loop) the water pump and the thermostat.

about a week after this I swapped in the zf5 and installed the hypermax kit, turned the pump up two flats and put the first set of stacks on it.

Got hot once coming across montana on the way out here. flushed the cooling system and refilled again, replaced the cap and made it here.

I have been working at a dealership so I flushed it a couple times there and the time before last I installed a coolant filter. The coolant stays the correct color but I think the system has deposits in it from the PO (S) before me.

I need to pressure test it and I guess I need a new radiator.

from what I understand these things have such a big cooling system that is so efficient they rarely get even kinda hot. I think mine is pushing the limit and I hope I havent already cracked the heads.

punk

 

[typ4]

I was just giving you crap justin. Actually it is under the hood that looks red from previous leaks.
I am wondering why mine runs so damn hot.????