so ive been showing signs of head lift on my pd150 hybrid vrs. pressure in the system after a hard drive and coolant coming out the overflow in the expansion tank. ive got some pd150 head bolts on order to hopefully rectify this.

 

so recently ive just been driving steady and keeping the boost to a minimum which has stopped the coolant coming out the overflow but ive noticed now that my radiator aint getting hot?? ive had the car out today for over an hour of steady driving, so obviously everything should be up to temp. both top and bottom radiator hoses are red hot with the top one feeling quite hard and radiator stone cold.

 

any suggestions?

air lock?

Blocked radiator or thermostat jammed like mine was, small piece of plastic was obstructing mine.

ok so just to add to this as its still doing it. I got home today and after a long drive the rad was cold as before so I sat with my foot on the accelerator revving the engine to 3k for a good 5 mins while someone kept checking the rad and slowly the rad started to get hot until it was hot right the way through. could this be the water pump???

Still most likely to be the thermostat broken up inside its housing and obstructing the water flow. Please check it first.

 

Nigel

My octy had this the other week,

Rad stone cold..but got hot when giving it some stick,,,

Plastic water pump impeller had sheared off.

Not sure if devs have the plastic impella???

ok just to add to this. as ive got an obd2 reader I thought id check the engine coolant temp readings on my way home from work. both readings from the dash and the torque app on my phone were the same up to about 65 degrees. then the one on the dash rose to 90 on the scale within the next half mile where as the reading on the app was still at 65 degrees. it slowly rose to 84 degrees over the next 5 miles or so and never went higher than that. it actually fell back to 80 when I put my heaters on. rad still stone cold whehn I got home..........

 

oh and ive had to put nearly half a ltr of coolant in it today :-(

Edited 11 October, 201312 yr by daz_vrs

What Evers going on..it's clearly not being pumped round the system.

Take the bottom and top hoses off the rad and plug a hose pipe through the system,both rad and engine..see if anything comes out.

With mine I removed the thermostat and could feel the impella had sheared off the water pump..I'm not sure about yours though as it a derv.

My fabs at home so can't check.