Hi can anyone help please. My range rover p38 4.0 v8 temperature gauge keeps going from normal then shooting to the red. The car engine is not hot I can put my hand on it so engine isnt really hot. I've changed the temperature gauge and sensor. Also changed the radiator both thermostats and expantion tank cap also flushed the system and new coolent put in but still the same problem. I don't know if there is a air lock as there is no bleeder valve. Can anyone shed some light on this for me please or no the best way to bleed the cooling system. The cab heaters do get hot inside someone said something about a heater matrix or something. Any help would be really great full. The car stills pulls strong and goes well no smoke etc and not leaking any coolent but the radiator hose is building up a lot of presure. Thanks
Nicktrackside
Active Member
I had the same thing after I replaced the expansion tank. It only stopped after slowly undoing the cap every time the gauge went into the red, only enough to get the coolant to fill the tank. I guess it had a air lock somewhere.
biketeacherdave
Well-Known Member
Sounds like your air locked alright you can fill from the rad top hose take the expansion cap off poke ur hose into the rad hose and fill once you got water coming out the expansion bottle and the top of the rad quickly connect the rad hose. Run it up and let the coolant level settle. Works for me.
I expect you have the common problem of an air lock in the stat easy fix is to drill a 3mm hole in the outer rim of the stat it doesn't have a wiggle pin like old style stats so traps air.
I expect you have the common problem of an air lock in the stat easy fix is to drill a 3mm hole in the outer rim of the stat it doesn't have a wiggle pin like old style stats so traps air.
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Sounds like an airlock somewhere, some P38s are easier to bleed than others, usual way is to park it facing up a hill, then carefully open the cap and 'burp' it. There are loads of threads on here - use the search facility.
Have you checked that the thin pipe from the top of the rad to the expansion tank is clear? - this lets any air at the top of the system bleed out into the tank. Blow it through.
Other than that, if it's pressurising and makes the hoses really hard, you may have a leaky head gasket. You could get a sniff test done which will identify exhaust gas in the coolant, or do a compression test.
Good luck.
PS - 2 thermostats
??? there's only one in a plastic body with about 4 hoses coming out of it, low down near the oil filter.
Unless you mean temp sensors, there are 2 of those . . .
Alastair
Have you checked that the thin pipe from the top of the rad to the expansion tank is clear? - this lets any air at the top of the system bleed out into the tank. Blow it through.
Other than that, if it's pressurising and makes the hoses really hard, you may have a leaky head gasket. You could get a sniff test done which will identify exhaust gas in the coolant, or do a compression test.
Good luck.
PS - 2 thermostats
??? there's only one in a plastic body with about 4 hoses coming out of it, low down near the oil filter.Unless you mean temp sensors, there are 2 of those . . .
Alastair
biketeacherdave
Well-Known Member
Just the 1 hole will do it
tomcat59alan
Well-Known Member
tomcat59alan
Well-Known Member
Had a few tipples by the time I posted, what's your excuse Dave?
biketeacherdave
Well-Known Member
difficult but not impossible iv done it to my spare stat thats sitting here ready to fit should i need to
