Sometimes, the bloody obvious can get overlooked!
This is project 14, the 2.5 Elite bought last week. Main problem - chronic overheating. Basically runs at 95 all day until you slow down then goes way over 100!!!! Not good. In view of the previously done oil cooler, decided to remove and flush radiator. As I had a known good spare radiatior I fitted that one to save time after flushing the system thoroughly. Observed that the aircon rad was a bit green looking.
Anyway, problem still there. next port of call was the water pump which was leaking slightly. May as well do the cambelt at the same time.
So, this morning stripped out the radiator again, removed the air con rad to see that it was fairly blocked airwise with green gunge from a leak. Cleaned up the area and enjoyed the huge space gained to work in. A tip here guys, remove the air filter box when working on aux tensioner. It makes access a huge amount better.
Then me and Laidback removed all the cambelt access stuff and agreed that the water pump looked f-f-f-f-f-f-f-f- not very good. Close inspection of the cambelt revealed that it was almost brand new and the tensioners too. So that stayed put after confirming the timing was spot on.
Water pump off and reveals that the seal had dislodged and partially disintigrated. So, new pump on and rebuild, confident that it would all be fine now.
Sat with the engine running and it sat at 95 degrees. Great. Off for a run. Overheating the same with the fan cutting in at about 99 degrees.
Me and Laidback were talking at some length about possible blockages, thermostats, thermo switches, extra fans blah blah. I said that I had a spare speedo pod and would swap it just to rule out the gauge giving us false alarms. You can guess what can't you? It was. Changed the pod and the temperature is spot on normal again. Changed it back and it 'says' overheating, change back again and its all fine.
So, this major fault was nothing more than the guage itself. The car will no doubt benefit from the newer radiator and the coolant flush. And the pump was definitely cacked. But this just shows how the blindingly obvious can sometimes be just that!
Total work about 3 days. Total job? 10 minutes!!!