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No pressure on upper radiator hose

Moparjack 489

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Hey folks ,
On my upper radiator hose I never get pressure on it , it’s ok , or not ?

I have installed a overflow tank von meziere , and a radiator cap with a upper rubber seal too for get theoretically the the fluid back in the radiator if the engine cool’s down .

but I wonder why my Upper radiator hose never feel tight when engine is running . means like I never have a closed water circuit system ?
my cap not work properly ?
It’s seems my cap never tighten fully the radiator up , and let all the time a opening to the small hose to the overflow tank , right ?
And my overflow tank of course have also a emergency overflow drain.
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Pressure and temp are related in a closed system. Is your temp normal after warm up? Are you losing coolant over time?
 
Test your cap (or just replace it)
 
Are you having trouble with over heating? If not: if it ain't broke don't fix it!
Mike
 
Thermostat stuck? That would prevent flow to the upper hose.
 
If you don’t built pressure it means you have a ‘leak’ somewhere, assuming the engine is getting up to temp. Your overflow won’t come into play for building pressure. As mentioned, pressure test the cap but also pressure test the system. Anytime I’ve had this issue a new cap solved it.
 
Are you having trouble with over heating? If not: if it ain't broke don't fix it!
Mike
No , all fine with the temperatures , only wounder that I can squeeze the upper radiator hose and can press it in my hand
 
Thermostat stuck? That would prevent flow to the upper hose.
I not think the thermostat stuck , because if it stuck and not open all the time I will get a overhead quick . But as long my E-fans work I’m fine in temperature range
 
If you don’t built pressure it means you have a ‘leak’ somewhere, assuming the engine is getting up to temp. Your overflow won’t come into play for building pressure. As mentioned, pressure test the cap but also pressure test the system. Anytime I’ve had this issue a new cap solved it.

thanks , also toolmanmike , yes I test my cap already first I think the lower rubber on the spring not long enough to touch the surface of the radiator opening and seals my radiator only with the top rubber, and this means I have all the time a open connection between my radiator itself and my overflow tank where is also not seal because he have a overflow on it without any pressure opening spring or something like that ,
Thanks guys , I think you right , and anywhere my radiator cap sucks , and let a little opening in the lower rubber and alowed to bypass The water cyrcle to the overflow tank all the time and the system can not build up any pressure .
but by the way , is it important for anything to build up pressure in the system , if you not losen any water ?
 
No , all fine with the temperatures , only wounder that I can squeeze the upper radiator hose and can press it in my hand
The systems operate at about 14-15 psi. That is not much pressure and very easy to squeeze by hand.
 
The systems operate at about 14-15 psi. That is not much pressure and very easy to squeeze by hand.
Yes if the engine is running, but I mean if the engine is off after running it’s very squeezing soft , but I know if the engine is off on my station wagon and all the other mopars I had the upper radiator hose are very very tight and under pressure .
 
Fix it !
First I try a cap from my friends Charger , but this cap also not seal my radiator 100% . after I put my cap back again but in „ the other way“ just turn 180 degree and put on , now the cap seal‘s 100% as I should be . Crazy but works ....
 
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