I have a 2004 Disco 2.5 HSE 4.6L with 76K miles. A month ago my mechanic tells me I need a head gasket job, which he completed and the disco ran fine for 1000 miles, then all hell breaks loose.

Problem 1. Engine overheating - blowing coolant out the resivoir. Mechanic replaces thermostat, new resivoir and coolant. After about 80+/- miles, guess what's back (engine overheating again - no blowing coolant this time.)

I top up the coolant, check the oil (not milky or smokey) and drive it a short way (5 miles) while driving it at less than 1000 revs I notice the cabin not heating up (the heater is on), then the cabin heats up starting at 1500 revs to really hot at 3000 revs, like the revs control the level of heat from the system? Park the Rover. No coolant leaks on the ground under vehicle, no coolant smell or wetness on passenger-side front seat (heater core?)

So what is up here? when I rev the engine the coolant is moving through the resivoir (can hear and see it move) so is it a water pump issue or worse the recent headgasket job is already blown of the head is blown?

LR mechanic advice please! Thanks you!

 

It could be air in the cooling system, have the system bled properly per the manual and try again. ----------jneil

 

You either have a big air bubble in the cooling system or a cracked block.

 

Ok, bled the air out of the system per spec. All the same issues are back. Losing coolant 1/2 GA every other day. New thermostat, new headgaskets, no visible signs of blowing out the tailpipe, no engine/cylinder misfires, oil looks OK.

Could there be a leak in the heating system or heater core that could slowly lose coolant below the vehicle, but with no visable (sight/smell) within the vehicle?

 

Yes that is possible, also check the throttle body heater plate, that is a common leak point and it drips onto the valve cover.
if it is small enough it may evaporate before you notice it.

 

Spike555,

Who are the LR mechanics you prefer in West Michigan?

 

I do 98% of my own work so I really cant recommend any one.
For exhaust, suspension, wheel bearings I use Brian and Leo at Muffler Man on 28th st in Grandville.

If you need head gaskets, engine rebuild or other major engine work then I recommend Austin Jordon Engines on Clyde Park and 44th St in Wyoming.

Both places are hole in the wall shops but they know their stuff.

 

Mechanic found a gallon of "lost coolant" in the oilpan! Cracked Block or sleeve caused coolant issues. at 76K miles, motor is still under warranty.

Thanks for the help!

 

Talk about the agony and the ecstasy! Wow! That's the last place I would have looked.