Quick cooling question

Two quick questions

Turns out my overflow hose going to the overflow bottle was clogged so I replaced that.

Started the truck back up, it runs right below 210 everything seems fine. You grab the upper rad hose and its scorching hot, somethings not right.

Take off the upper rad hose where it meets the t-stat junction and you get steam and its dry as a bone.

So next thing I do is take off the t-stat housing it looks ok but for shit's and giggles I take the t-stat out and replace everything to see if it was the t-stat why I wasn't getting fluid.

Start it back up for like 10 seconds turn it off take off upper rad hose at t-stat and everything is nice and wet, thats a plus.

So go and buy a new t-stat clean everything up put back together test it out. Upper rad hose is still getting hot, but doesn't seem to be getting as hot.

Take upper rad hose off at t-stat and everything is wet, but I'm still getting steam coming out of the upper rad hose.

So my two questions are
How can you tell if you are getting enough water flow through your upper rad hose and should you be seeing steam coming out of the upper rad hose right after turning off the vehicle. (don't worry, I have a pressure release rad cap so no exploding rad fluid in my face to worry about)

Second, how hot should your upper rad hose be. The lower rad hose should be hot to my understanding, about 210 degrees, but I would think that the upper rad hose should be moderately cool.

Thanks in advance for the help. Once I get this all straightened out, next thing to do, is rip apart the dash to replace my heating unit, yippie!

Matt

The top hose is the water IN to the radiator, so it should be the hottest. The bottom hose runs the cooled water back in to the engine. I tested mine a few days ago with an infrared thermometer after the engine was run up to 210 on the gage, but just driving slow around town. The top and bottom hose read 150. The heater hose read 190. The tstat housing read 190 and the temp sensor (on the outside) read 230.

I think you need to close it all up and keep feeding coolant in to the radiator cap until it won't take any more. Let it run a while with the cap off. Then put the cap on. Be careful, it looks like that plastic tank could break easily where the cap goes on. Then put coolant in to your overflow tank until it's about halfway. Expect it to use up a little of that over the next few days of expanding and contracting. Then just add to the overflow as needed. When you use that pressure relief cap, the system of pulling coolant back in is defeated.

I did what you said, it only took a little bit more fluid so I must of had it pretty well full.

Ran it, seems to be ok, I didn't take the upper hose back off to see if there was steam will have to do another day just to double check.

Quick question tho, should the upper rad hose be like unsqueezeable. I can pretty much grab the hose and close it off all across the hose with just my fingers, shouldn't there be some sort of water pressure in there??

The upper radiator hose should be full of coolant, hot or cold.

If you are pulling off that upper radiator hose, and not losing a shitload of coolant each time, you have a problem.

You have the thermostat installed correctly, right? If you install it backwards--no coolant in upper radiator hose, but you would see steam coming from the t/stat housing.

I think normally you can squeeze the upper hose. I'll check next time I warm up. If the tstat was in backwards, wouldn't it overheat?

I don't think you can even install the t-stat backwards because the pointy tip hits the inside of the engine block.

And I don't think you should have coolant coming out of the upper rad hose when you pull it off b/c gravity pulls the coolant back but i dunno

Open or closed system if you have air and not coolant in the upper radiator hose you have a problem, not a gravity thing, the system is either full of coolant or you have air in the system.

Speaking of open or closed--what year/engine?

heh sorry about that
its a 98 with a 4.0

I think you need more coolant in the system. Continously removing the top hose will not accomplish that. To the contrairy, you will loose coolant and allow air into the system.

Do you have a recovery tank? Make sure it is good and the hose connecting it to the radiator is not leaking;...tight at both ends and not kinked in any way.

Your radiator cap is very important. What is the pressure? Does it seal tight on the radiator? It must be able to prevent the coolant from leaking outside. It must hold pressure inside the cooling system (16 PSI) when the engine is hot. It must allow excess coolant to flow from the radiator to the recovery tank also when the engine is hot and the pressure exceeds 16 PSI. It must also allow coolant to return from the recovery tank to the radiator when the engine cools.

If there are no obvious leaks in the system, you should close it and not open it again especially when the engine is hot.

Fill the radiator and replace the radiator cap (with a new one of the recommended pressure) securely.

Fill the coolant recovery tank above the full mark.

Start the engine and allow it to come up to proper operating temperature.

Shut it off and allow it to cool. Add cooolant to the recovery tank as needed. This should be repeated several times after short runs. Do not open the cooling system again (radiator cap and hoses).

Steam at the radiator hose indicates insuficient coolant in the system as you already know. Taking the hose off every time the engine is hot will not fix it.

this may be kind of a stupid reply, but at 210 degrees shouldnt that hose be burning hot and possibly create steam? lol. the hose will be squeezeable... honestly if it was me and i had a radiator shop neat my place, i'd go there and do a coolant system flush... that way they flush ur system so it would obviously show everythings working...it may cost a shiny penny, but your problems found, addressed and fixed..

to add to this... if it's running fine at 210, why u trippin?, if its not overheating, what seems to be the problem?

nominated

MaxxXJ said:

this may be kind of a stupid reply, but at 210 degrees shouldnt that hose be burning hot and possibly create steam? lol. the hose will be squeezeable... honestly if it was me and i had a radiator shop neat my place, i'd go there and do a coolant system flush... that way they flush ur system so it would obviously show everythings working...it may cost a shiny penny, but your problems found, addressed and fixed..

to add to this... if it's running fine at 210, why u trippin?, if its not overheating, what seems to be the problem?

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Because the system is obviously not working properly. Kind of like that guy who butchered his shackles and doubled them up or something. They worked, for a little while.

thats why i suggessted a system flush it will clean out anything in the flow of his system. at least if that doesnt work, he can knock that off his list of possible problems, cost between 50-150 dollars to do it... could save the cost of an engine... or he could pull the radiator and or just the bottom plug and drain it ,fill it up... maybe drain it and while it drains feed water into the system to flush it and make sure the radiator's cleaned out, then refill it with new stuff

MaxxXJ said:

thats why i suggessted a system flush it will clean out anything in the flow of his system. at least if that doesnt work, he can knock that off his list of possible problems, cost between 50-150 dollars to do it... could save the cost of an engine... or he could pull the radiator and or just the bottom plug and drain it ,fill it up... maybe drain it and while it drains feed water into the system to flush it and make sure the radiator's cleaned out, then refill it with new stuff

Click to expand...

That's still just throwing money at a problem without properly diagnosing it first.

You want the doctor to tell you he's not sure what kind of cancer you have so he'll just prescribe you random drugs and hope they find the cure before you die a painful and horrible death?

bigalpha said:

That's still just throwing money at a problem without properly diagnosing it first.

You want the doctor to tell you he's not sure what kind of cancer you have so he'll just prescribe you random drugs and hope they find the cure before you die a painful and horrible death?

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fine... im not going to argue with you im done with this topic, thats just what i would do, and because he's a doctor im sure he's seen that problem before so he would be more accurate at finding the problem and fixing it.

MaxxXJ said:

fine... im not going to argue with you im done with this topic, thats just what i would do, and because he's a doctor im sure he's seen that problem before so he would be more accurate at finding the problem and fixing it.

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You still missed the whole point, lol.

OP: does your overflow tank have coolant in it or is it dry?

bigalpha said:

You still missed the whole point, lol.

OP: does your overflow tank have coolant in it or is it dry?

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i understand your point, alot of mechanics will nickle and dime you to death before they find the problem, troubleshoot just the same as i would.

MaxxXJ said:

this may be kind of a stupid reply, but at 210 degrees shouldnt that hose be burning hot and possibly create steam? lol. the hose will be squeezeable... honestly if it was me and i had a radiator shop neat my place, i'd go there and do a coolant system flush... that way they flush ur system so it would obviously show everythings working...it may cost a shiny penny, but your problems found, addressed and fixed..

to add to this... if it's running fine at 210, why u trippin?, if its not overheating, what seems to be the problem?

Click to expand...

Wow...

overflow bottle has plenty of fluid in it. I just replaced the hose going from the rad to the overflow bottle, so theres definitely no kinks or clogs in that hose anymore.

I've done the, start the motor let it run but it just seems that the upper rad hose just doesn't seem like it has enough water in it. The overflow bottle, never goes down so I would think that I have enough fluid in the system.

The system doesn't need a flush, I did that already when I replaced the entire system a year ago. I just replaced the t-stat and rad cap for the second time before I made this post and it seems to be better but I'm still not convinced.

I might just have someone shoot my upper rad hose with a heat gun to see what temp its running at in there so I have a basis to go off of.

Then take it from there, unless anybody has any other ideas.

thanks for the info thus far guys
Matt

Try pulling the upper hose off of the therm housing and pouring coolant directly into the hose. If you can pour some in, then you had an air bubble in the radiator. You might try that, but if that was your problem it would probably be overheating....:dunno: