rotorbeetle

Howdie
need to find out what will cause presure in water system
I have a 13bt S4 no overheating smoking nothing
but every time i go for a long drive 200kms +
temp running between 69deg - 78deg depending on how heavy my foot is speed +- 85-100mph get home leave the car to cool down after 2-3 hours there is pressure in the water system
all i do now is when i know i drove long distance
before i drive again i open the radiator cap release the pressure top up with antifreeze and off i go

What would cause this & should i worry
like i said no overheating smoke etc nothing like that
just pressure after long drives

TIA

jantore

A freind of mine had he same problem. He had a ruptured water gasket. I tink it might be the same problem u have.

And u need to do a rebuild.

NZConvertible

Always check the simple things first. The radiator cap controls the cooling system's pressure. As water heats up it expands, but since it can't increase in volume because the system's sealed, pressure increases instead. The radiator cap bleeds off coolant into the overflow bottle to maintain system pressure at a constant value (0.9bar or 13psi normally). When the engine is switched off, the system cools and the coolant contracts. The radiator cap lets the coolant get sucked back into the system from the overflow bottle. If you're having pressure problems the first thing you should replace is the radiator cap.

rotorbeetle

my water bottle have a pressure cap and my radiator
the one on my radiator seals the system so nothing reaches the bottle oops
and to make things worse my bleed pipe is blocked off pipes there but has like a big ball bearing thing in the pipe so no water flow through there
I will get this sorted
Thanks again

CCarlisi

uhhhhhhhh....I'm not sure what you just said but I have the same symptoms. https://www.rx7club.com/forum/showth...5&pagenumber=1

As far as I know all my ***** are in the right place though If you have a sec please expand on what you said.

Thanks,

Chris C.

CCarlisi

.

rotorbeetle

I fixed mine and seems ok
All I did was unblock my bleed pipe and replaced my radiator cap with a single seal instead of the duel seal
Before I did this I had the same as you but the car had to warm up to 60+ deg C wait till cold for +- 8 hours and the pressure stayed and the temp left
So I use to bleed the system manually and off I went again for a couple kms and so on
Did you replace your cap yet?
And you are sure there is nothing blocking water flow etc any were in the system? and that there is no air still trapped somewhere?
When I put my new radiator in my rx7 I had the same thing all I did to solve it was to take out the thermostat take the garden hosepipe put it into the radiator and ran it for 5-10 mins on the grass with water flowing through the complete system put every thing back and no more problems this was on a converted first gen from 12a to 13BT
Hope you come right
CYA