Thread: Troubleshooting Summer Overheating

Hoges:
Surely the Heater Matrix isn't required for general cooling of the Vehicle?
At this stage I'm measuring 105 Degrees across the top of the Radiator and as much as 115 Degrees at the Oil Sump...

Thus I'm fairly confident the Temperature Guage is correct and accurate....

Originally Posted by BusinessConnected

Alright:
So I've run the Liquid Intelligence through the system... Radiator Inlet and Outlet look very, very clean and a fair few bits of "Gunk" Fell out from the Bottom Radiator Outlet when I was flushing it out.

However rather than fixing the problem it now seems worse!!!

Car will overheat at pretty much any outside temperature... I'm just at a complete loss to workout whats causing the issues.

With the Radiator Cap off I can see the Coolant streaming from the Radiator so there seems to be Coolant Flow from Water Pump etc....

I'm just soo annoyed right now I'm ready to head to Ebay with both my P38's and associated parts!!!!!!!

Originally Posted by BusinessConnected

Surely the Heater Matrix isn't required for general cooling of the Vehicle?

I think you're correct regarding the heater matrix not being required for the general cooling of the vehicle. My previous comment was only meant to address the reason for you not getting hot air from the heater.

Getting back to the overheating problem. When you cleaned the cooling system some of the gunk from the system may have travelled through the breather hose that leads from the top of the radiator to the coolant header tank and may have blocked one or both of the orifices that are in the header tank. To start with disconnect the breather hose from the radiator at the header tank end, then get compressed air and blow into the plastic pipe on the filler neck in order to clean out any blockage that may be in the breather orifices. Please note that there are two orifices on the breather – one in the filler neck and another one at the end of the pipe that descends vertically into the header tank. You may have to place your finger over the orifice in the filler neck in order to direct more pressure to the other one.

When you have done this run the engine without the radiator cap fitted until the engine is up to normal running temperature and make sure that the thermostat has opened – run engine at fast idle to try to expel any pockets of air out of the system. When you're confident that there is no air in the cooling system then put the pressure cap on and run the vehicle as you normally would and see what happens. Hopefully this will eliminate the worsened heating situation and in stead of it being very bad it will return to just being bad.

Originally Posted by BusinessConnected

Hoges:
Surely the Heater Matrix isn't required for general cooling of the Vehicle?
At this stage I'm measuring 105 Degrees across the top of the Radiator and as much as 115 Degrees at the Oil Sump...

Thus I'm fairly confident the Temperature Guage is correct and accurate....

Coolant flows through the heater matrix all the time whether the heater is on or off. Just wondering whether there was any blockage in the heater matrix which would cause problems. Good to be able to confirm the accuracy of the temp gauge.

So I drained the Radiator and followed the "RAVE" Coolant fill method and Fast 2000rpm Idle to try and alleviate Air Pockets etc in the system...

Unfortunately didn't do much, Car still went up to Top of White/Into Red with Warning Light. Only way I could turn the temperature down was to Disable Air Con, and Turn on Heater Full Blast... This got it down to around the "2pm" Position at the First White "Notch" above normal...

All I could see when I was doing my fast idle bleed was some Steam rising from Coolant Expansion Tank, and of course the level went down a bit each time until it seemed to stay pretty stagnant...

How long should I be doing the 2000rpm Idle for?

My other P38 is supposed to be getting New Radiator, Thermostat & Water Pump next week... I wonder whether I should just take them all and see if they resolve the issues with this car....

At least the Radiator and Thermostat should be a quick "check"....

Water pump is a half-hour job to change, for the price outta the uk you could change it once a year!

Originally Posted by BusinessConnected

My other P38 is supposed to be getting New Radiator, Thermostat & Water Pump next week... I wonder whether I should just take them all and see if they resolve the issues with this car....

At least the Radiator and Thermostat should be a quick "check"....

The radiator and thermostat would be the most likely suspects. You've got nothing to loose by trying them.

I'm going to grab all 3 tomorrow.... I think I'll change Radiator and Thermostat first because its easier... then Water Pump if issue still occurs