Hello, newb to site and Supras. Just bought an 88 n/a auto with 134k on chassis and supposedly 60k ish on replacement 7m-ge(no supporting paperwork). I've searched threads and tried some stuff but only made limited progress. 1st-bypassed heater valve completely with 90* elbow-no change. 2nd-replaced 180* thermostat with 192*-no change. 3rd-raised front end and made a mess-no change. 4th-backward flushed heater core, lots of rusty water came out but no obstructing material-now have heat IF the motor is turning 2k or better but will cool back down when returned to idle. Question-could the water pump be weak? It doesn't leak and the bearings seem good as it doesn't wobble when grasped. Is this a common prob?
Also no heat
- Thread starter Footbraker
- Start date
You need to check (feel) the temp of the hoses going to the heater core. On full hot, both should be hot. If both are hot, the problem's not with the heater core.
The "heater valve" you bypassed is just a shut-off valve that kicks in when the a/c is set to full cold. I believe interior air temp is regulated by the air flow doors and not by varying the heater core temp. Check the on-line TSRM - there wasn't much changed in the heating system ferom year to year for MKIIIs.
Good Luck, Skip
The "heater valve" you bypassed is just a shut-off valve that kicks in when the a/c is set to full cold. I believe interior air temp is regulated by the air flow doors and not by varying the heater core temp. Check the on-line TSRM - there wasn't much changed in the heating system ferom year to year for MKIIIs.
Good Luck, Skip
I had the same issue with my 7m I finally replaced water pump and everything fixed itself. I would say that it would be your next step.
Also make sure you have enough coolant in it...
Also make sure you have enough coolant in it...
