Vr4play

Earlier this year I installed a Mishimoto performance aluminum radiator, new thermostat, water pump and all new hoses on my 02 Suburban. The engine coolant temperature is rock solid at 195 deg. Every since I did this the heat is not quite what it once was. I have to turn the heater **** all the way to hot to get warm heat. If I put it in the middle it is cool, 3/4 is slightly warm. The blend door seems to be working as is should. Before doing anything is would be warm in the half position. I ordered a newer style thermostat and housing and installed it and the head would burn you on half. The problem with that set up was the temp ran 215 deg the whole time and I have my e-fans programmed to come on around 210 so they never turn off. The nipple feeding the reservoir seems to be small enough to act as a restrictor so my gut is telling me something is weird with this particular thermostat. I threw away the old thermostat so I can't try that so I'm thinking of just getting a factory GM thermostat and see what that does. Doesn't make sense that the engine temp is correct but the heat still isn't warm. Seeing if anyone else has experienced anything like this. Thanks

strutaeng

Your AC controller is the one with the rotary *****, right?

I wonder if when you replaced your radiator something got dislodged and clogged the heater core? What about your rear heater? Does that one work fine? I wonder if you could temporarily disconnect the heater return coolant hose and see if you have flow coming out? Your airflow is okay? Your truck has a cabin filter, right?

The heater in my 99 Silverado is pretty darn hot. Once it heats up 1/4 of the heat is as much as I can tolerate. My 06 Suburban has that auto climate control and it's got a mind of it's own, probably needs replaced or my temperature vent is wonky.

RB04Av

Tried flushing the heater core?

MikeGyver

iTrader: (5)

Expanding on the two above responses, did you use any stop leak additive before changing everything out? That will plug up a heater core, or a stock radiator, too.

zz454Chevelle67

This fixed mine last winter, blows hot air now, well maybe not now since I dropped a valve last week.

Vr4play

I haven't had a chance to fuss with this lately but will have to do something in the future. It's starting to get cold. I am going to replace the water pump and thermostat again as the replacement water pump had started leaking so I threw the original one back on. This all started as a fix to a leaky water pump that turned out to only be bad gaskets. 2 new replacement water pumps both leaked so the stock one got reinstalled. When I do the water pump I'll flush the heater cores but the front and rear heat both feel about the same. I'll update when I figure it out. Thanks

Fullpower

.
. Source for Low grade, Leaky Water Pumps ?
ebay or Amazon ?

Vr4play

The 1st one came from rockauto. The second one came direct from Melling.