[demarest652]

I have an 04.5 lly and here recently it seems like its been running hotter usually it runs a little under 210 now it seems to be running about 215 or so. also anytime it is 45 degrees or less it won't warm up then all of the sudden the temp gauge will almost hit the red then it will cool off back to around 210. anybody have any ideas?

 

[TheBac]

Thermostat sticking? Low coolant level? Programmer messing with the gauges?

 

[TxChristopher]

Blown head gasket. better do something about it or you will end up with warped heads.

 

[demarest652]

Blown head gasket? Ive never had a diesel blow a head gasket but ive blown headgaskets on plenty gas and methanol motors and theres usually water in the oil and oil in the water or water in the exhaust and i dont have a problem with either of them here. It actually acts like a thermostat sticking. i just wondered if anyone had ever had a problem like this before i start throwing parts at it. thanks for the help guys.

 

[Ben46a]

I would test the thermostats first. I would find it hard to beleive a headgasket with no compression in the coolant.

 

[TxChristopher]

Blown head gasket? Ive never had a diesel blow a head gasket but ive blown headgaskets on plenty gas and methanol motors and theres usually water in the oil and oil in the water or water in the exhaust and i dont have a problem with either of them here. It actually acts like a thermostat sticking. i just wondered if anyone had ever had a problem like this before i start throwing parts at it. thanks for the help guys.

The thing is, there are 2 thermostats and a bypass. So if the back thermostat "stuck" (it isn't) you would still have flow through the other one. There will never be a surge. If the front stat stuck (it isn't), you would have bypass flow and still no surges. If they BOTH stuck (they aren't) you would have bypass flow and still no surges but it would overheat quickly.

What is happening to you is the temp is flashing to red from boiled coolant then falls back to "normal" because the temp sender is uncovered, as in reading AIR temp inside there not COOLANT temp.

It is common on these motors for the gasket to be blown but not find coolant anywhere. Only when boost comes along does it blow by, but then it is evaporated. Dexcool evaporate quickly and cleanly, so it burns out quick, not like the old green stuff. Pour some of each on the ground and you will see. The Dexcool disappears but good old green is next to impossible to wash away.

 

[way_out_there]

Blown head gasket? Ive never had a diesel blow a head gasket but ive blown headgaskets on plenty gas and methanol motors and theres usually water in the oil and oil in the water or water in the exhaust and i dont have a problem with either of them here. It actually acts like a thermostat sticking. i just wondered if anyone had ever had a problem like this before i start throwing parts at it. thanks for the help guys.

Maybe it hasn't happened before, but how many times before were you running a 125hp tune, like you have in your sig? Can't say that this was the absolute cause to such a problem, but it doesn't help...

 

[demarest652]

TxChris, This is supposed to be a place to help each other and to learn. I ask those questions because i am trying to figure out what my problem is and make sure thats what it is before i tear into it. You have no reason to treat me like im an idiot.

 

[4wheeln]

TxChris, this is supposed to be a place to help each other and to learn. I ask those questions because i am trying to figure out what my problem is and make sure thats what it is before i tear into it. You have no reason to treat me like im an idiot.

Wow.

He gave an opinion and then he explained his opinion. I did not read anything aggressive to it. You posted a question for input and have received input. I don't understand the reason for the insult.

TxC has had a blown headgasket. Also the possibility that both thermostats are sticking is extremely low. It is not difficult to change thermostats so you can change both. If problem solved, then great, if not, then you need to start looking at other suggestions. The temp range for the t-stats is usually stamped on them.

Good Luck with your truck.
4wheeln

 

[demarest652]

He has no reason to be such a smarta$$ i have read some of his other posts and he is that way to everybody. Im sorry thats just not how people talk to each other where im from but i do appreciate everyones help. I just deal with people everyday and i know how i treat people when they ask me a question and i expect to be treated that way. I am in the paint, drywall, and insulation business and if anyone here was asking me a question about that i wouldnt respond in that way.

 

[way_out_there]

Have you done any work on your truck yet? I think a few of us would be interested in the outcome.

I don't see where TXC badmouthed you, but it would be ironic if he was correct.

 

[idahofox]

Brandon,

Before changing any parts, I would clean the stack with low pressure water.

FWIW/with respect:

 

[demarest652]

The Stack?

 

[TxChristopher]

TxChrist, this is supposed to be a place to help each other and to learn. I ask those questions because i am trying to figure out what my problem is and make sure thats what it is before i tear into it. You have no reason to treat me like im an idiot.

WOW.

I dunno what to tell you guy. You asked for help, and I offered that I suspected a blown head gasket. Then you questioned my input with the reasons why you thought it could not be a blown head gasket but sticking thermostat instead. Then I explained why I thought it would not be, based on the way the truck is behaving and my knowledge of the layout of the system.

I have seen more than one Duramax with a blown head gasket. Maybe yours is not, who knows, but the symptoms are there.

I don't think anything I offered warranted that reaction from you, other than maybe you didn't wanna hear the worst case.

Either way you are getting air over your temp sender, causing those big swings. Good Luck.

 

[demarest652]

Im sorry i believe that what i said came out wrong and was harsh. I do apoligize. I do very much respect the opinion of everyone on here and i greatly appreciate the help. I definately dont want it to be a blown headgasket. The low coolant light started coming on over the weekend so i filled it up and realized it has a crack in it so i ordered a new one today should be here in a couple days hopefully that fixes the problem. ill let everyone know how it goes. Again i am sorry txchris. and thanks for all the help

 

[TxChristopher]

Im sorry i believe that what i said came out wrong and was harsh. I do apoligize. I do very much respect the opinion of everyone on here and i greatly appreciate the help. I definately dont want it to be a blown headgasket. The low coolant light started coming on over the weekend so i filled it up and realized it has a crack in it so i ordered a new one today should be here in a couple days hopefully that fixes the problem. ill let everyone know how it goes. Again i am sorry txchris. and thanks for all the help

No big deal, its cool. :Thumbup:

So the res had a crack? Good, if thats the source of the block getting low on coolant and would fit the symptoms (coolant disappearing from block causing temp sender to be uncovered). Hopefully it is the source and not a result of another problem. Question I would still have is how did it get cracked????

 

[CBRJohn2000]

Im sorry i believe that what i said came out wrong and was harsh. I do apoligize. I do very much respect the opinion of everyone on here and i greatly appreciate the help. I definately dont want it to be a blown headgasket. The low coolant light started coming on over the weekend so i filled it up and realized it has a crack in it so i ordered a new one today should be here in a couple days hopefully that fixes the problem. ill let everyone know how it goes. Again i am sorry txchris. and thanks for all the help

I know that you already opened up to the possibility of a blown head gasket. I also understand where you are comming from with the oil water thing....it is more common for a gasket to let go between the cyl and either oil or water galleys, but I have also seen them go between the cyl without hitting any gally or directly to outside without hitting anything else.

I know you and TxC have already straitened your disagreement, and my post is not intended to aggravate that, just inform. I hope that TxC is wrong to be honest as I am sure he does. But for the record....I think he's right.

Again....this is not intended to be snooty or anything like that, just informative.

 

[idahofox]

The Stack?

THE RADIATOR AND CAC !

 

[demarest652]

ok so i just did some testing. I took the coolant tank out, and i did a little rigging on the crack for now. so far not leaking. so with the truck at idle with the cap off the tank it has no problem. If you put the truck in gear and set the brake and stall it up till it builds boost it does overflow but it also overflows if you rev it in park when its not building boost. that kinda confuses me, but like i say most of my experience isnt with the diesel motor i know with gas motors usually if you rev it up the coolant level drops. also when you shut it off the coolant level rises considerably..... Let me know what you think. Im still prayin for it not to be the gasket but i have a feeling thats going to be the verdict

 

[TxChristopher]

Is the upper hose hard? Does it quickly get hard (as in pressurized) right after the truck is started? Does it stay hard after the truck is shut off and cooled down?

Of course we are talking with the cap on.... just to be sure we are on the same page.