Water Pump Pressure Readings?

[Dan_J]

hey all,

just after some info as i searched and gave the rb20 manual a scan.

what pressure readings should i be getting on the coolant system?

i'm using the12mm hoses up top near the intake manifold with a t-piece barb on a pressure gauge and my readings are when car is cold running.... 0 psi and 13psi when hot 70-80c unless somehow said lines are no good for readings to be taken.

blew a heater hose so i replaced hoses and a thermostat with a rb25 unit and is there ment to be a lil bit of black rubber circle ring on it near the opening( tried to see if i could remove it but seemed pretty solid so left it) as i usually just run rb30 thermostats and they dont have this ?

i know something is up as car is overheating 80c while idling, top hoses are hot and bottom are cold/normal so must be water pump or newly installed thermostat

thanks

Edited January 19, 2013 by Dan_J

[scotty nm35]

That pressure seems about right, and the 80c temps are pretty good too. What is the issue?

It's a good idea to test thermostats before you use them, dunk it in hot water and see what temp it opens...

[Dan_J]

really zero pressure when cold?

was about to start on the water pump but figured i'd confirm on pressure and the rubber ring on the new rb25 thermostat before i go to the effort

^^^^ it takes me a decent drive to get the car up to 75 normally...... and these temps are just sitting in the driveway raising quickly

i know something is up as car is overheating 80c while idling, top hoses are hot and bottom are cold/normal so must be water pump or newly installed thermostat

EDIT it doesn't stop at 80C , turned it of at 86 as it was getting abnormally hot

thanks

Edited January 19, 2013 by Dan_J

[mad082]

the standard thermostat is set to open at 82 degrees. anything up to about 90, or even 95 at worst case scenario is normal on a really hot day for the original cooling system, as it gets less effecient as it gets older and gets build up in the radiator. if you had a brand new thermostat and radiator then 82 to 85 degrees is normal.

[Dan_J]

thanks scott might just pull out the thermo' again and double check before i do anything to the pump

[89CAL]

Standard water pump creates some flow not pressure. The pressure comes from the heat making the coolant want to expand. So at ambient temp it should have no pressure, when at operating temp should have whatever your radiator cap is rated at. They are 0.9bar from memory so 13 psi does sound right.