Hi All
I recently replaced a water pump and coolant hose. Everything went well until I started her up. after about 4 to 5 minutes the temp started to climb above normal? I shut off and checked around. I found the lower hose going into the thermostat was still cold? So I figured that was the problem. so I fitted a new one but it's still doing the same thing? after 4 to 5 mins it starts to overheat. The lower section of the radiator is cold to the touch the upper section is warm. What am I missing?
All the best John.
car is 2001 disco series 2.

 

your radiator is stuffed. you can buy a new one or flush the hell out of your original, but it will never perform at max efficiency again.

 

Are you saying its blocked up? I was starting to think that. So its not the thermostat?
Thanks for your help.
John.

 

Its a bit early to jump to that conclusion. First please detail for us the method you used to properly bleed your cooling system after this work was finished. There is a proper method which you can search here for.

I would make sure it was bled properly before throwing any money at parts. When you do search notice how many people fail to bleed the cooling system properly.

 

that's true. I guess you can say I jumped to conclusion. purging air is essential.

 

I removed the bleed screw, raised the expansion tank from its clip and filled until coolant came out of the top bleed hole. Ran the car, then added as needed. I screwed the screw in and occasionally unscrewed it partly to make sure id didn't have air bubbles. Also I ran the heater on full. I did notice it didn't get hot out of the vents? Is that the correct method? I have done this a few years back but maybe I'm doing something wrong here.
Thanks for your help. john.

 

Just for clarification. If there was any air in the system, it would effect circulation and do what I described?
Thanks John.

 

I believe no heat is a symptom of huge air bubble in heater system. Not the only cause but on the list of related issues.

Your bleeding sounds ok, did you do all of that with the engine stone cold? Even the unscrewing partially of the bleed screw should be done stone cold.

Many people here report having to bleed every morning (before turning engine on) for a few days to get stubborn air out. Others park uphill the night before and then bleed with the nose up AND the overflow tank elevated first thing in the morning.

Another trick is to open the bleed screw, again cold engine, not running, and top up there with a small amount of coolant.

Keep trying, do everything with the engine stone cold. repeat as needed.

And as long as you were on the subject, do you still have the stock thermostat?

If it does come down to replacing parts, get the OEM 180 degree grey one from Lucky 8. it will run quite a lot cooler.

 

Thanks Dave. I will try what you said and report back.
All the best John.

 

Let's take a few steps backwards...was it overheating "before" you did the initial water pump and hose replacement? The way you have it worded here (above), it sounds as though it started overheating right afterwards...and you were just basically doing maintenance.

Also, did you replace the coolant hoses directly connected to the thermostat? Maybe, you buggered/plugged up the stat while doing so?

Just trying to wrap my head around how and when this happened/started.

Brian.