So, following on my earlier posts about my overheating LR, today I dropped in a new thermostat to replace the one that my mechanic obviously did not replace like he was supposed to. So far, so good. Just driving locally, but no overheating so far.

However, I still have a lot of pressure in the coolant hoses.

That said, I have no benchmark. I don't know really how much pressure is supposed to be in the hoses. Is there some baseline way of measuring how much coolant pressure there should be? I can depress the hoses maybe a quarter inch at most. Is that normal?

Thanks,

Dan

 

It is a pressurized system so they will be hard just depends on your definition of hard. Re-bleed your coolant it takes 2 minutes. Just unclip the expansion tank and raise it up on the battery box, while you are holding it crack the coolant bleed screw (loosen it before hand so you can open it with your fingers) then leave it open until coolant pours out.

 

The relief valve is designed to open at 20 psi. Are you blowing any coolant out the relief valve?

 

By relief valve, you mean the bleed valve on the upper hose?

With the engine running, the bleed valve spits out coolant. So that suggests there's no excess air in the system, right? Is there anything else that would cause excess pressure in the line other than air?

I keep saying excess pressure, because before I replaced the thermostat and put in new clamps, it was blowing one of the upper hoses off, and I have the same amount of to-the-touch pressure in the hoses now.

I drove it for about 50 minutes today without any noticeable issues.

Dan

 

He means the relief valve in the expansion tank cap.

 

you want to open the bleed screw on the radiator hose with the expansion tank raised, the cap off. When you open the bleed screw, any excess air that is in the hose should be released. You may still have air in the heater core that may take some time to work out. If you open the bleed screw when the engine is running it will just spit out coolant, assuming that you have some in the truck. Good luck. Phili

 

can someone help me please . my 02 disco 2 just redid headgaskets, new rad,tstat,waterpump. when i start up and let it idle to burp system rad hoses are not pressurized, temp goes to normal . then take for test drive . runs fine till i get on the power to climb a hill . temp rises and radiator hoses pressurize . atlantic british says fan clutch might be the cause ? any suggestions , thanks

 

If you are moving at 45 mph the air flow from forward motion makes the fan only a small issue. You can drive with fan removed. Just don't stop or go slow.

If clutch was bad you would have heat rise at idle.

The heat gauge is not accurate. It will point at 50% from 130 - 240F. You want 180 - 200. Use a scanner or Ultra Gauge to see real temps.

When you hit 212F the electric fan should come on, so check fuse, relay, and spin the blades, should freewheel, not be siezed up. The viscous fan should spin only part of a revolution when twirled and hot. If freewheels, replace.

If you hear sounds like water and bubbles rushing thru pipes under dash, that could be exhaust gas or air bubbles in coolant. There is a chemical test for exhaust gas in coolant, little over $50. If head gaskets were slapped on without flatness check or machining heads, then.......