High Pressure In The Cooling System

[MintyFresh]

What would cause high pressure in my radiator?

Ive just replaced the old \'standard\' radiator with an uprated one after the original split down the seam but im still experiencing too high a pressure.

Any ideas on the cause?

[TRex]

Possible compression leakage.
  Duff Rad caps.
  System Blockage.

[MillSpeed]

What\'s making you think the pressure\'s too high?

[Clover]

Thats what the garage told him. But the garage don\'t really know anything about the rotary engine.

[MillSpeed]

The cooling system pressure is governed by the AST cap, it should be 0.9bar. Might be worth just swapping that first as last.

[Clover]

is that the cap where he puts the water in. How do u no what pressure the cap is. also does that have anything to do with the amount of psi he is running? i think its 14

[MillSpeed]

Nope it\'s the one on top of the Air Separator Tank (AST), the little black plastic tank mounted on the intercooler. The pressure rating will be marked on the cap in eithr bar or psi depending on if it\'s the original one or not. When you say the amount of psi he\'s running, do you mean boost pressure? That won\'t have anything to do with the coolant pressure (well, not unless the coolant seals have failed on the intake side of the rotors movement).

[TonyBlair]

is that the cap where he puts the water in. How do u no what pressure the cap is. also does that have anything to do with the amount of psi he is running? i think its 14

Hi mate,

I don\'t (98% sure) think the boost pressure from the turbo\'s (usually 14 psi) has anything to do with the pressure of the coolant system what so ever.

The AST (air seperation tank) cap, shown in the picture, is \'spring-loaded\' - not where you are suppose to put water in. When the pressure in the coolant system reaches 0.9 bar of pressure the spring in the cap is pushed up enough to allow water to over-flow into the coolant expansion tank tucked away in the left-hand corner of the engine bay (see picture).

If you take the AST cap off you should find the lid on the inside of it is springy, it should move quite freely, if it doesn\'t then that could be your problem.

Hope this helps... I don\'t know what else can cause high pressure in the coolant system really. You may be better off taking the car to a rotary specialist rather than your local garage.

Cheers
Jon