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upper radiator hose

5K views 10 replies 7 participants last post by  Dmax1776 
#1 ·
Silly question but what does it mean when the upper radiator hose is sucked shut on a cold engine.
 
#3 ·
Check your Radiator cap. Its not returning coolant from the catch tank. (like a check valve). Coolant gets hot and expands, flows into tank .Coolant in radiator cools down and can't suck back. hoses collapse.
 
#4 ·
It 'can' be a clogged surge tank cap.

However, I see it all the time.....look over at the coolant level in the surge tank, and it's low. Top it off to full, upper hose keeps it shape. :thumb

For the Dexcool used in the system to perform correctly as an inhibitor between dissimilar metals, it's important to keep that tank topped off, lest air accumulates in the system, which can cause deterioration/rust/coolant sludge.
 
#7 ·
Book calls for 8hrs labor.
I think more like 6 if you know what you're doing.

Or, all weekend if you don't. lololololol

How'd you go from a flat hose to a failed Water Pump?
 
#9 ·
See post 4.
Low on coolant will draw the hose flat.
 
#10 ·
The coolant expands when warm and the reservoir cap lets air out.

When the coolant cold, the coolant contracts-- and the reservoir cap is suppose to let air back into the system-- but if the cap is sticky-- it may not let air in, so the system is under a "Vacuum" and the hose collapses.

As noted above, clean or replace the reservoir cap.

When the waterpump is bad, it usually leaks coolant out of a small vent hole [weep hole]. That weep hole is located above the lower radiator hose where it attaches to the waterpump.
 
#11 ·
Changed the air filter in my truck today and I haven't driven it for 4 days , popped hood and noticed my upper hose collapsed . Drove for a bit and pulled over and checked when engine was up to temp , the hose was back to normal. I'll check the cap later or tomorrow . Thanks for the suggestions guys . Oh and the level in the tank was normal and at the full line with the engine cold and sitting for 4 days .
 
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