Overheating and Loss of power

[DerekT]

Having had loads of problems with water leaks, originally from water pump, (now replaced), then overheating, (replaced thermostat) and now a leaking radiator which I am about to replace. Problem is that while I was looking for the source of the leak, I had topped the water up to full after a major boil over, (with the engine cold), drove about 100 yds then the engine note changed and suffered drastic loss of power. Have not put the new rad in yet, but is there any sensor or software switch that may cut the engine power in an overheat situation? It happened so suddenly.
Any suggestions much appreciated!

[Budgie]

Which engine & age of Disco are we talking about?

If it's 300 TDI, how did you refill the system, did you use the header tank, the raditor or the cap on top of the thermostat housing?

With overheating there is a chance of warping the cylinder head which will also cause the head gasket to go so are there any signs of water in the sump oil, a pressurised cooling system or oil in the cooling system?

[DerekT]

We are speaking about TD5 disco, therfore filled via expansion tank. Have taken head off to check gasket, - nothing obvious but a possible crossover between cylinder 3 and exhaust port. It was when I was in getting new head gasket from Landy agent the parts man seemed to think there was some protection device that cut power in the event of overheating. Was he imagining this? meanwhile I am trying to put everything back together!

[charliedenny]

We are speaking about TD5 disco, therfore filled via expansion tank. Have taken head off to check gasket, - nothing obvious but a possible crossover between cylinder 3 and exhaust port. It was when I was in getting new head gasket from Landy agent the parts man seemed to think there was some protection device that cut power in the event of overheating. Was he imagining this? meanwhile I am trying to put everything back together!

yep there is if the sensor on the front of the top hose (front of head)
this is the temp sensor
if the engine feels it is overheating it will go into limp home mode
I had a faulty sensor on mine and it gave me a couple of scares on the motorway last week changed it on Tuesday hope it has cured it!

did you bleed the cooling system? bleed screw on the top of the top hose.

[rbm]

how hot did it get, if it has been cooked then you could well be looking at new turbo and injectors - we have had to change them on the last 2 very cooked td5's we have done.
also the oil cooler gallery (warps and leaks oil) and water pump mounting to block seal leaks (beteen the big alloy air con/alternator mounting brkt and the block) the fly wheel dosn't like being very hot either.


hope it is not to bad.

[DerekT]

Don't think it got over-cooked. Have put all the engine back together now but land rover garage supplied me with the wrong radiator. - Not their fault, the box part number was correct but it contained a defender rad with a pipe coming out the front!. The disco rad pipes all come out the back. Should be picking up the new one tomorrow - will let you know how it goes!

[tonywitney]

Don't think it got over-cooked. Have put all the engine back together now but land rover garage supplied me with the wrong radiator. - Not their fault, the box part number was correct but it contained a defender rad with a pipe coming out the front!. The disco rad pipes all come out the back. Should be picking up the new one tomorrow - will let you know how it goes!

How did it go then, Derek?

[DerekT]

Ok All back and working now .. I hope! Got the correct Radiator and also changed temp sensor as a precaution while I was at it. Started first time even after all that major surgery, power back no normal.

PS Do all land rover owners need to have two pairs of hands, each with universal wrist joints to work in their engine compartments?? (Plus deep pockets!)

Thanks for the help and interest out there.

Derek