Water system

[Milex]

It’s not been my weekend so far , suspension probs etc, now just noticed top hose all sucked in , my neighbor said it could be the seal on radiator cap causing it, I’ve looked around engine bay and checked on floor for drips but can’t see any , car runs just under 1/2 way on temp as it always has, any ideas guys many thanx

[Herbie]

As always, Google is your friend.

[BachelorDays]

16 minutes ago, Herbie said:

As always, Google is your friend.

Lots of info in there on how to check/diagnose. Hope you get it sorted easily.

[Delphius1]

The expansion tank on the RX is not pressurised. When the coolant heats up and expands, it pushes past a spring-loaded valve in the radiator cap and fills the expansion tank.

When the coolant cools and contracts, a vacuum is creates and the coolant in the expansion tank is sucked past a second valve in the radiator cap to maintain the coolant level.

If the return valve is stuck, or the small bore pipe from the expansion tank to the radiator neck is blogged, the coolant can't return to the radiator.

The vacuum caused by the contracting coolant causes the hoses to collapse. 

The good news is you have no leaks in the coolant system, but it does need seeing to as it will affect coolant flow at colder engine temperatures.

An aftermarket radiator cap shouldn't break the bank and neither should checking the expansion tank hose for a blockage.