99 Chevy Silverado 1500 4x4 Overheating PLEASE HELP!

[tramz]

we did it just idling and only drove it once when we thought it was working fine and the gauge is maxing out light coming on saying check coolant and the lower hose isn't hot but like I've said several times we've already went through 2 stats a new water pump all new hoses and flushed everything

Another thing is to disconnect the upper radiator hose from the radiator side and run the motor until the t'stat opens or gauge runs hot. If t'stat opens and circulation cycles and if your indication of it running hot is only the gauge you may have a bad gauge or wire fault. Not sure about '99 but if you have a temp sensor it may be faulting.

[JoshWalkerMedia]

Ok i appreciate a lot of the help y'all have given but everyone from what you are saying you are speaking like its the older model 99 and it is not the t stat is on the lower radiator hose not the upper and there is no radiator cap on the radiator it is fully enclosed this is the late model 99 we are talking about here the t stat is one build in piece stat and housing are made together and connect into the lower part of the water pump.

[brucelimerick]

I will take a look at my 01 tomorrow. I have never had this one apart, everything is still original on the engine. No matter what though it is a simple system, the heat of the fluid in the engine has to control the t-stat. Though GM engineers have been known to pull a few boners in their time. To tell the truth this seems pretty hokey to me. The stat is going to hunt all over the place. Think about the logic, the stat gets warm and starts to open, the cold water from the rad washes over it and cools it off and it closes, heats up and the whole process starts again. It won't work right until the rad fluid is hot at the bottom. Sounds like it was designed by an idiot. Hot rises and water flows downhill. Any time you screw with the laws of mother nature you are going to have problems.

So back to troubleshooting, you need to get a temperature of the fluid at the top of the engine or rad. You need a number so you can check your warning light and the functioning of your t-stat. The hottest engine t-stat I ever installed was on a galaxie 500 and it was 193F. Sounds to me like your surge tank is normally pressurized but you should still be able to take the cap off cold and it won't overflow. You may be able to get a idea of the temperature from that tank fluid but it will be lower than the engine. I will look at mine tomorrow, it is a 4.8L

[efritz]

once the engine gets hot, grab the throttle on the side of the throttle body and rev it up a bit, the upper hose should swell up quite a bit if there is an obstruction in flow. If there is then you need to find out what it is, whether it be a bad radiator or clogged coolant passage or bad tstat. If it doesn't swell then your pump shaft may have spun off of the impeller which I have seen, or the belt is routed incorrectly, Try running with the Tstat pulled out of an old housing using a pliers to rip it out, just to see if it's a culprit, but it's unlikely.

[j-ten-ner]

Why don't you do us a favour and take a pic of the broken piece or what it looks like.

Maybe it's better to start over from the beginning.

Did you plug any pipes or hoses while repairing the coolong system to prevent coolant from spilling out?

 

It almost feels like you're pulling our legs a little.

 

so long

j-ten-ner

[JoshWalkerMedia]

Why don't you do us a favour and take a pic of the broken piece or what it looks like.

Maybe it's better to start over from the beginning.

Did you plug any pipes or hoses while repairing the coolong system to prevent coolant from spilling out?

 

It almost feels like you're pulling our legs a little.

 

so long

j-ten-ner

 

 

once the engine gets hot, grab the throttle on the side of the throttle body and rev it up a bit, the upper hose should swell up quite a bit if there is an obstruction in flow. If there is then you need to find out what it is, whether it be a bad radiator or clogged coolant passage or bad tstat. If it doesn't swell then your pump shaft may have spun off of the impeller which I have seen, or the belt is routed incorrectly, Try running with the Tstat pulled out of an old housing using a pliers to rip it out, just to see if it's a culprit, but it's unlikely.

 

I will take a look at my 01 tomorrow. I have never had this one apart, everything is still original on the engine. No matter what though it is a simple system, the heat of the fluid in the engine has to control the t-stat. Though GM engineers have been known to pull a few boners in their time. To tell the truth this seems pretty hokey to me. The stat is going to hunt all over the place. Think about the logic, the stat gets warm and starts to open, the cold water from the rad washes over it and cools it off and it closes, heats up and the whole process starts again. It won't work right until the rad fluid is hot at the bottom. Sounds like it was designed by an idiot. Hot rises and water flows downhill. Any time you screw with the laws of mother nature you are going to have problems.

So back to troubleshooting, you need to get a temperature of the fluid at the top of the engine or rad. You need a number so you can check your warning light and the functioning of your t-stat. The hottest engine t-stat I ever installed was on a galaxie 500 and it was 193F. Sounds to me like your surge tank is normally pressurized but you should still be able to take the cap off cold and it won't overflow. You may be able to get a idea of the temperature from that tank fluid but it will be lower than the engine. I will look at mine tomorrow, it is a 4.8L

Unless I've said it wrong in the initial post which I'm sure i didn't here it all is again as simple as possible

 

IT HAS NEW UPPER AND LOWER RADIATOR HOSES

ALL NEW HOSES THAT GO FROM THE RESIVOUIR TO THE PUMP AND TO THE HEATER CORE(BOTH OF THE HEATER CORE HOSES)

HAS NEW WATER PUMP

AND IS ON ITS SECOND BRAND NEW TSTAT

AND I HAVE FLUSHED THE BLOCK, RADIATOR AND HEATER CORE

THE RADIATOR IS LESS THAN A YEAR OLD AND HAVENT HAD PROBLEMS WITH IT AT ALL

 

THE WATER DOES NOT CIRCULATE FULLY THE RES LINES GET HOT BY THE WATER PUMP THE UPPER HOSE GETS HOT SO ITS FLOWING INTO THE RAD THEN IT STOPS IN THAT LOWER HOSE

 

i can't give picture of the "broken part" as there is no broken part its not flowing correctly idk why

 

I appreciate the help but constantly telling me its the stat over and over doesn't help its on a second brand new stat so i do not know anything else i can tell you.

[JoshWalkerMedia]

I will take a look at my 01 tomorrow. I have never had this one apart, everything is still original on the engine. No matter what though it is a simple system, the heat of the fluid in the engine has to control the t-stat. Though GM engineers have been known to pull a few boners in their time. To tell the truth this seems pretty hokey to me. The stat is going to hunt all over the place. Think about the logic, the stat gets warm and starts to open, the cold water from the rad washes over it and cools it off and it closes, heats up and the whole process starts again. It won't work right until the rad fluid is hot at the bottom. Sounds like it was designed by an idiot. Hot rises and water flows downhill. Any time you screw with the laws of mother nature you are going to have problems.

So back to troubleshooting, you need to get a temperature of the fluid at the top of the engine or rad. You need a number so you can check your warning light and the functioning of your t-stat. The hottest engine t-stat I ever installed was on a galaxie 500 and it was 193F. Sounds to me like your surge tank is normally pressurized but you should still be able to take the cap off cold and it won't overflow. You may be able to get a idea of the temperature from that tank fluid but it will be lower than the engine. I will look at mine tomorrow, it is a 4.8L

 

 

also its all installed correctly idk what looking at your 01 will do also mines a 5.3 v 8 different from your 4.8 v 6 in terms of serpentine belt and so on

 

as for the info about the stat its the same factory recommended one that when you walk into orileys and say i need a stat for this make and model its the one they give as well as my new water pump and hoses

 

i agree yes its like the stat isn't opening up to let it flow but Y its all new and flowing the correct way

 

BUT when i say i flushed everything i just ran water through them but the water came out clean and clear and just as fast as it was pouring in from the opposite side so i have no clue anymore

 

[Duelin]

When it over heated how hot did it get? Have you check it for a blown head gasket?

[brucelimerick]

The 4.8 is a v8, the 305. You need to know the temperature of the engine fluid. How do you know it is overheating? Engine light on the dash? Temperature guage? They could be broke. Rad hose is hot, 180 feels hot to a hand but perfect for an engine. Your gauge cluster could need rebuilding, they only seem to last 10 to 15 years.

You need to identify the problem. Right now you are making assumptions from a symptom and tossing parts at it. That obviously hasn't worked. Step one, get a temperature.

[Duelin]

The 305 is a 5.0.

[JoshWalkerMedia]

The 4.8 is a v8, the 305. You need to know the temperature of the engine fluid. How do you know it is overheating? Engine light on the dash? Temperature guage? They could be broke. Rad hose is hot, 180 feels hot to a hand but perfect for an engine. Your gauge cluster could need rebuilding, they only seem to last 10 to 15 years.

You need to identify the problem. Right now you are making assumptions from a symptom and tossing parts at it. That obviously hasn't worked. Step one, get a temperature.

i have nothing to check the temp with ik for for a fact however that it is not circulating that is clear as day as the res fills up as it over heats and doesn't circulate any further

 

 

 

 

When it over heated how hot did it get? Have you check it for a blown head gasket?

we have heated it to what the gauge says is 260 and my light come on in the truck saying check coolant and after you shut the truck off a red light comes on and states engine overheated and as for a head gasket we haven't pulled it apart as we don't have the time or money for that and there is no coolant in the oil and no oil in the coolant and no coolant is leaking into the compression either.

[Duelin]

You don't have to tear it apart to check for a blown head gasket. One example of a blown head gasket is the hot gases get into the coolant passage and super heat the coolant. And can build up the coolant pressures real fast. What I usually do is sniff the radiator with an exhaust gas analyzer to see if exhaust gases are getting into the coolant system.

[ifixedit]

^{Two things, first I've read of problems with the fan clutch causing the overheating, so maybe is something to look into. Second, I recently replaced the water pump and thermostat on my 98 Yukon, filled it up until it was full and took it for a drive. First drive the temp gauge slowly crawled up to about 240 F and I was thinking here we go, it's gonna overheat, then all of a sudden the gauge dropped to 180 F and has been fine since. I attributed it to the system just needing to purge the air. When I returned home I just needed to top it off. If your fan clutch checks out o.k. have the heat on full when you first take it out so it purges all the air from the system.}

[butzers09silverado]

did you you check the belt install to make sure you have it on right, i know it sounds stupid but i didn't see you confirm that was done...

[JoshWalkerMedia]

did you you check the belt install to make sure you have it on right, i know it sounds stupid but i didn't see you confirm that was done...

Yes i have installed everything correctly nothing is running backwards either