Overheating promblem

[Joey01]

Hi 

I have a Nissan skyline 370gt and after 30 mins of driving it keeps overheating the thermostat has been changed the head gasket has been checked an radiator but there fine this all happened after I washed it any suggestions would be appreciated thank you 

[GTSBoy]

It is possible that the impeller vanes in the water pump have corroded away. Would need to have spent some time with bad coolant (ie rusty water) or possibly with an electrical problem (that would drive galvanic corrosion).

Otherwise it sounds like head gasket.

[Murray_Calavera]

4 hours ago, Joey01 said:

head gasket has been checked

What was done to check it?

[Joey01]

2 hours ago, Murray_Calavera said:

What was done to check it?

I’m not sure mate the mechanic reakons he checked it over and it was allguds do you have any tips on how I can check it myself??

[Joey01]

3 hours ago, GTSBoy said:

It is possible that the impeller vanes in the water pump have corroded away. Would need to have spent some time with bad coolant (ie rusty water) or possibly with an electrical problem (that would drive galvanic corrosion).

Otherwise it sounds like head gasket.

Hey mate thank you for the reply  do you have any advice on how I can find out if the water pump is the problem??  

[GTSBoy]

You'd need to add a way to observe/quantify the water flow rate through a radiator hose.