cooling system questions

[Mat Grant]

Hi all,

I've got a pressure cap on my 1UZ, but the nature of the car is such that the pressure cap is not the highest point in the system. It is topologically where it was on the original soarer, but as the bonnet is very low, it is low down.

So I have a separate filler cap on the heater system as the heater hoses are the highest point on the cooling system, higher than the filler plug on the thermostat housing.

I'd like to simplify this and fit a pressure cap in place of the filler cap on the heater hose where it comes off the engine, ie the "send" to the heater, and remove the current pressure cap - from looking at the system diagram it is open to the pressure of the cooling systems at all times. Even if the heater valve is shut and there is no flow, there is still pressure. Does anyone have a view on this? Any issue with the cap being located like this?

The next question is, as I have to find a smaller Japanese style filler cap - what is the PSI for the pressure cap for a 1UZ (1992 1UZ engine)?

I did a search but didn't find this info - Any advice appreciated

Thanks, Mat.

 

[super_red_sc]

The manual indicates 22-24 psi

 

[Zuffen]

Interesting I use 13psi and looking at parts suppliers they also supply 13psi for an LS400.