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Camaro820 11-21-2011 08:10 PM

upper radiator hose
 
so just recently i was giving the engine a little tune. while i had it running and it got to operating temp (160 degrees) i heard a loud clicking coming somewhere between the upper radiator hose, the thermostat, and the heater hose from the intake. after looking closer, i noticed that the upper radiator was collapsing. ok, i replaced it and its still doing the same thing. and also too, when i shut it off, you can hear all of the coolant rush back into the radiator and when i had the cap off to fill it, every time you heard that click, coolant came gushing out of the radiator. would i ultimately fix that if i get a hose with that spring inside?

dgcantrellsr 11-21-2011 08:20 PM

Check for stuck t-stat.

Camaro820 11-21-2011 08:25 PM

i did that too. i took it out and put it in boiling water and it opens up. i thought that would have been it too. but what it seems like what its doing is that the hose collapses, but not completely, and it builds up enough pressure and pushes through and thats when you hear that click... its kind of hard to describe.

SDLuck 11-21-2011 10:40 PM

What car are we talking about?Are you sure you ran it with the cap off and got all the air out of it?Is there a hole in the t stant to bleed the air out?

Camaro820 11-22-2011 06:01 AM

When I tried to get the air out, after it got to operating temp coolant would come out in waves. But there is no bleeder either.

cliff tate 11-22-2011 07:26 AM

top hose colapsing
 
Quote:

Originally Posted by Camaro820
When I tried to get the air out, after it got to operating temp coolant would come out in waves. But there is no bleeder either.

sounds like rad plugged ,causing the water pump to cavitate,this would aerate coolant and poss.reason for air in the system.also check rad cap as there is a vacuum relief which should stop the hose co lapsing.with a clean rad and system bled top hose wont collapse

Camaro820 11-22-2011 08:14 AM

And when I would take the cap off when it was hot, you can hear all of the fluid rush back into the rad. So get a new cap and see what that does?

oldbogie 11-22-2011 01:16 PM

Quote:

Originally Posted by Camaro820
so just recently i was giving the engine a little tune. while i had it running and it got to operating temp (160 degrees) i heard a loud clicking coming somewhere between the upper radiator hose, the thermostat, and the heater hose from the intake. after looking closer, i noticed that the upper radiator was collapsing. ok, i replaced it and its still doing the same thing. and also too, when i shut it off, you can hear all of the coolant rush back into the radiator and when i had the cap off to fill it, every time you heard that click, coolant came gushing out of the radiator. would i ultimately fix that if i get a hose with that spring inside?


I'm guessing by your handle this is a Chevy in which case I'd expect the following:

Given that the return hose is always on the pressure side of the pump, it should never experience collapsing while the engine is running. It sounds like the thermostat is installed upside down or there is some other blockage in the return system. This would prevent coolant circulation, except through the heater bypass, while the engine is running. The upper hose would collapse as the pump inlet is applying a suction that can't being sufficiently fed with the bypass. Another possibility is that the if the intake has been off and returned such that the manifold gaskets which may have only an open return stamped hole at one end are installed backwards preventing the return of coolant. Also, some Chevy's source the bypass at the rear of the intake, in which case a normally installed gasket with only a single sided return hole could cut off the bypass which would keep the radiator and upper hose under a negative pressure until the thermostat opens, if the thermostat is installed properly.

When the engine is shut down, the pressure holding the thermostat shut is relieved and it pops open where the radiator that has a partial vacuum in it from the pump's attempts to feed itself will now surge the coolant trapped within the engine into the radiator.

With the cap off the, this coolant will escape because it is very hot and expanded to where its volume is greater than that of the system.

Another possibility is that the if the intake has been off, and returned that the manifold gaskets which may have only an open return stamped hole at one end are installed backwards preventing the return of coolant. this could find a way at shut down to suck coolant back into the return by way of the heater bypass system drawing backwards from the pump return, through the heater core, then back to the common return passage on the intake manifold.

I would expect any of these conditions to be accompanied with an overheat condition, although I could see that so much boiling is taking place within the block that the sensor is trapped in steam instead of coolant, therefore, unable to present reliable temp readings. the clicking sound you heard I suspect is trapped steam escaping explosively inside the cooling jackets.

Bogie

Camaro820 11-22-2011 01:41 PM

Yes it is a Chevy. And I did have the intake off. But I also used the se gaskets as before and installed the same way. It never did it then. I thought it was the thermostat and possibly put it in upside down but it wasn't and it is working properly. As far as overheating, it really doesn't go above 170 and it has a 160 installed now. A friend of mine had the same problem minus the clicking sound and what he did to fix it was installed a wire inside the upper hose and that fixed his minor overheating and collapsing hose.

oldbogie 11-22-2011 02:26 PM

Quote:

Originally Posted by Camaro820
Yes it is a Chevy. And I did have the intake off. But I also used the se gaskets as before and installed the same way. It never did it then. I thought it was the thermostat and possibly put it in upside down but it wasn't and it is working properly. As far as overheating, it really doesn't go above 170 and it has a 160 installed now. A friend of mine had the same problem minus the clicking sound and what he did to fix it was installed a wire inside the upper hose and that fixed his minor overheating and collapsing hose.

The upper hose should not require a wire coil to keep it from collapsing. This is a problem with the suction side (lower) hose so these have a a spring in them. But the upper should always be seeing pressure from the pump, the cap, and the thermal expansion of the coolant. Usually before the thermostat opens you can squeeze the upper hose closed but when the thermostat opens and pressure is applied this becomes most difficult to do. If the the upper hose is collapsing, then something very unusual is going on to cause not only a loss of pressure on the return side but the formation of less than atmospheric pressure inside that section of the cooling system. Assuming this is a normal Gen I Small Block. If this is an LT1 or 4 or has a new LS series engine then the issues get more complex and you could see the return hose collapse.

Bogie

Camaro820 11-22-2011 03:17 PM

Wow you're making me sound like an idiot! Lol dr automotive. So then check the bottom hose? The car is an 84 camaro with a crate 383 stroker and I'm pretty sure the hoses are still stock. So check the bottom hose?

Camaro820 11-24-2011 12:43 PM

Yep. Clogged radiator. I opened the cap and you can see a bunch of crud inside floating around and when I drained it... WOW!

123pugsy 11-24-2011 02:26 PM

Good to hear you found the problem.

Thanks for posting it.

Camaro820 11-24-2011 02:38 PM

I wish I could have shown a picture of it. It almost reminded me of sandy water and when I drained it, the inside looks like pure BLAH!


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