Hard upper radiator hose
Thread Starter
Racer
Joined: Aug 2003
Posts: 460
Likes: 15
From: Belgium /
Hard upper radiator hose
So i've been redoing my suspension and complete rear end and installed a new dewitts radiator, new hoses, new radiator cap and a new thermostat.
the car sat on stands for almost 2 years, i filled up the new radiator and fired up the car with the cap off, and let it run for a couple of minutes and added liquid.
but now when I put the radiator cap on the top radiator hose get pretty firm, I am afraid that I might blow the hose.
what could be the problem here ??Air in the system ??
I don't smell gas fumes in the radiator.
everything worked great before installing the new radiator ( old one had a hole in it )
the car sat on stands for almost 2 years, i filled up the new radiator and fired up the car with the cap off, and let it run for a couple of minutes and added liquid.
but now when I put the radiator cap on the top radiator hose get pretty firm, I am afraid that I might blow the hose.
what could be the problem here ??Air in the system ??
I don't smell gas fumes in the radiator.
everything worked great before installing the new radiator ( old one had a hole in it )
Melting Slicks
Joined: May 2012
Posts: 2,192
Likes: 343
From: Allenton Wisconsin
If you are concerned about there being to much pressure in the system, the radiator cap is the pressure release. Get it checked, 16 or 17 psi is max for our systems. In my cars it takes at least 3 heat cycles before I get the coolant level right and that is 2 inches down from neck. Also put the pressure tester on the radiator and see how much pressure the engine is producing, a bad head gasket? T
Team Owner
Joined: Sep 2006
Posts: 31,200
Likes: 4,287
From: Westminster Maryland
Hi sm,
Is the upper hose getting hot….is the thermostat opening?
A new radiator hose will typically feel considerably firmer than an old hose which tends to be quite soft.
Regards,
Alan
Is the upper hose getting hot….is the thermostat opening?
A new radiator hose will typically feel considerably firmer than an old hose which tends to be quite soft.
Regards,
Alan
Racer
Joined: Aug 2013
Posts: 339
Likes: 54
From: Fayetteville NC
Try this, pull the radiator cap off and start the car. Let it warm up and depending on what thermostat (180?)you have, you will see the coolant flow when it opens. This will test if you have flow. Believe it or not, I've heard about people who installed a new radiator and forgot to pull the plastic caps/plug from the input and output tubes. Not saying yours came with them or not. Just checking.
Last edited by ENCSDOUG; Feb 14, 2017 at 03:57 PM.
Racer
Joined: Apr 2016
Posts: 493
Likes: 65
Test your cap, if it holds 16 or 17 lbs of pressure, I don't think you'll ever blow that top hose.
I made both hoses on mine from some steel tubing, and sent it to Phoenix for coating, inside and out. This was the first test fit, without clamps on either end. So far, so good
I made both hoses on mine from some steel tubing, and sent it to Phoenix for coating, inside and out. This was the first test fit, without clamps on either end. So far, so good
Racer
Joined: Aug 2013
Posts: 339
Likes: 54
From: Fayetteville NC
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Melting Slicks
Joined: Mar 2005
Posts: 2,093
Likes: 297
From: Midlothian VA
So i've been redoing my suspension and complete rear end and installed a new dewitts radiator, new hoses, new radiator cap and a new thermostat.
the car sat on stands for almost 2 years, i filled up the new radiator and fired up the car with the cap off, and let it run for a couple of minutes and added liquid.
but now when I put the radiator cap on the top radiator hose get pretty firm, I am afraid that I might blow the hose.
what could be the problem here ??Air in the system ??
I don't smell gas fumes in the radiator.
everything worked great before installing the new radiator ( old one had a hole in it )
the car sat on stands for almost 2 years, i filled up the new radiator and fired up the car with the cap off, and let it run for a couple of minutes and added liquid.
but now when I put the radiator cap on the top radiator hose get pretty firm, I am afraid that I might blow the hose.
what could be the problem here ??Air in the system ??
I don't smell gas fumes in the radiator.
everything worked great before installing the new radiator ( old one had a hole in it )
If it wasn't the coolant would boil.
The tightness of the upper hose is due to this pressure.
There's always "air in the system". Why? Because you cannot compress a liquid. As the coolant gains heat it expands which means it takes up more space in the cooling system. For this reason there's always some type of "expansion" area which is why you're instructed not to overfill your system. When you do the pressure cap lets go and the coolant pukes all over the ground.
Instructor
Joined: Aug 2016
Posts: 235
Likes: 28
From: Fort McMurray Alberta
Test your cap, if it holds 16 or 17 lbs of pressure, I don't think you'll ever blow that top hose.
I made both hoses on mine from some steel tubing, and sent it to Phoenix for coating, inside and out. This was the first test fit, without clamps on either end. So far, so good
I made both hoses on mine from some steel tubing, and sent it to Phoenix for coating, inside and out. This was the first test fit, without clamps on either end. So far, so good
USAF - That looks pretty sharp !
OP - You've got some good advice from the posters
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
The upper radiator hose is the "pressure-side" hose....so it is going to get harder when the pump is operating. And your cooling system is not going to build abnormal pressure unless it is getting close to overheating. The only way the fluid is going to build pressure is if it is overfilled (and is a 'closed' system without an overflow tank) or if it turns to steam--which is not good.
Your system is fine.
Your system is fine.
Last edited by 7T1vette; Feb 15, 2017 at 01:04 PM.