Sounds air locked,
try reving it to a couple thou RPM for a few mins' with the heater valve open/hot,
I usually sit in with my hand on the screen vents and it on defrost until the heat comes through,
Though this can take a while.
Though the ideal would be a bleeder valve/screw in the return pipe from the heater matrix.
I did fit one to a problem vehicle,
can't remeber which one but it was a pain,
got the bleeder of a Renault traffic in the breakers.
|