Annoying coolant visit workshop s55

[rooferboy1959]

New radiator few months ago, plus hydraulic pump, keep getting intermittent engine temp spike, was stuck in motorway traffic a few weeks ago no problem as temp never went beyond 90c, today in moving traffic spiked to 100c and coolant visit workshop came on, no external leaks what so ever, been in merc independent with no fault codes. When it spiked put heater on hot, took a couple of minutes b4 hot came through but temp didn't come down. Us thus a sign of a failing water pump.

 

[mioba]

Did you fit gen parts

 

[rooferboy1959]

Yes, £5,000 worth

 

[Uncle Benz]

Air lock possibly, or bad thermostat. Delay on the heater suggests air lock to me. A block test just to be sure of the head gaskets might be prudent too.
A radiator fan module fault will show a fault code and usually MIL

 

[rooferboy1959]

Had the block tested twice once by nj solutions and one I did with chemical test, no sludge in oil and no white smoke, really annoying as mercedes indie can't find any issues