Overheating - Hissing Sound From Tstat Housing Area

[Lincoln Jealous]

ive been working on my ls for a few days now , after replacing the tstat housing, i went for a test drive and built up engine temp and coolant pressure, IT OVERHEATED AGAIN, but this time i checked under the hood and saw no leaks, i just heard a little HISSING coming from the tstat area,

I think it could be wear and tear of the ford hose clamps that might let air to escape, im planning on replacing all the clamps with new ones tomorrow, but has anyone else experienced a hissing sound- knowing that its air escaping somewhere,

this is making the car over heat now, once i fix this issue, i should be all set,..



any ideas on what to do

i mean i drove it for 10 minutes, no issues, started going faster, and it slowly went into overheating, drove until the red temp light came on and pulled over, checked under the hood, no leaks, just a small hiss, like a tea pot, haha im sure its the hose and i need a better clamp, but any ideas appreciated thanks!

just replace clamps and tighten all bolts and try again??:L

 

[joegr]

No hissing sound, but I did have a small hose in that area leaking where it connected (04 LS). I tugged on the hose and it popped off. I replaced the factory spring clamp with a screw down clamp resolved that problem.

 

[Quik LS]

the cooling tower - where the t-stat is - is the highest point in the system - so that is where you always will hear the boiling. there is a little line running from near the top if it to the degas bottle, where overflow runs back into the degas tank. So there is always a little air pocket right at the lid of the cooling tower.

the noise would suggest boiling coolant. so either the issue is a air leak in/around the coolant tower or 'somewhere else' and the system is boiling at a lower temperature than designed. If the system can't hold pressure the boiling temperature is not raised, therefore you boil before designed.

now - since you just replaced the cooling tower - maybe you still have air pockets? and need to rebleed the system? - it is a little tricky.

 

[pagluy]

Does it hiss only while in gear? Mine is doing this, haven't gotten it checked out yet. When I shift through the gears the hiss subsides as it pops out and comes right back when its in gear. In park, no hiss at all.

 

[Lincoln Jealous]

Does it hiss only while in gear? Mine is doing this, haven't gotten it checked out yet. When I shift through the gears the hiss subsides as it pops out and comes right back when its in gear. In park, no hiss at all.

it hisses after the engine gets to its hottest point, its a small hiss like air is escaping, but i havent got a chance to check it today, but i will check all the hoses, thanks people!