I used a vacuum bleed and fill (Mishimoto kit), and I noticed after I sucked it down, filled, and bled the radiator top and started it up, the cabin heat wouldn’t warm up even after a while idling at operating temperature.
The process that ended up working for me was:
1) Pressure test (difficult because the Mishimoto adapter threads didn’t fit all that well - fine for vacuum, but it wanted to blow off under pressure
1) Suck Vacuum
2) Lift coolant into the system that I blended into empty distilled water jugs
3) Bleed Radiator top
4) Start car, bring to operating temperature turn heat on full and “enjoy” the cold air coming out. Let the car cool off.
5) Hook up the vacuum system *again*, pull vacuum until the coolant starts foaming, then shut off the valve, and *hold* at vacuum. Wait patiently for a minute or so, and you’ll start to see some tiny bubbles come up into the coolant reservoir
6) Once the bubbles stop, release vacuum, then apply and hold vacuum a second time. More bubbles will come up.
7) Repeat sucking down a third time, at which point bubbles finally stop coming up.If you do get more bubbles,
8) Start the car again, warm up and enjoy the heat with the system finally fully evacuated.
It seem the heater core/valve wants to trap air bubbles because there’s a low point in the lines between the heater core and the rest of the coolant system. After I finally figured it out the first time when the heat wouldn’t warm up after doing the flush, I ended up repeating for a rinse/fill and the final fill with the new radiator, and every single time, I had to vacuum fill, warm up the car first, cool and then repeat pulling vacuum 3 times before bubbles stopped coming up, at which point the heat would come on right away.
I tried the vacuum hold/foaming thing before starting the car so as not to wait for the cooldown, but no matter what it took running the car and then 3x vacuum purging to get all the air out.
Haven’t had a problem since, even driving the car hard on a warm day.
I think the heater lines and possibly the cylinder head just have high spots that hold a little air even after running the car for a while, and it seems like it doesn’t come out of the system even after running the car unless you pull vacuum and hold/wait.
Also, don’t be fooled - the stacked plate oil heat exchanger under the oil filter is a serious little unit and it is capable of pulling a decent amount of heat out of the oil, not just an oil warmer. I’ve used that heat exchanger style for work, and they work quite well.
The moral here is that the factory oil cooler pulls a lot of extra heat into the cooling system that the radiator has to deal with, and adding an external oil cooler will take some heat load off the radiator and reduce coolant temperatures.
The process that ended up working for me was:
1) Pressure test (difficult because the Mishimoto adapter threads didn’t fit all that well - fine for vacuum, but it wanted to blow off under pressure
1) Suck Vacuum
2) Lift coolant into the system that I blended into empty distilled water jugs
3) Bleed Radiator top
4) Start car, bring to operating temperature turn heat on full and “enjoy” the cold air coming out. Let the car cool off.
5) Hook up the vacuum system *again*, pull vacuum until the coolant starts foaming, then shut off the valve, and *hold* at vacuum. Wait patiently for a minute or so, and you’ll start to see some tiny bubbles come up into the coolant reservoir
6) Once the bubbles stop, release vacuum, then apply and hold vacuum a second time. More bubbles will come up.
7) Repeat sucking down a third time, at which point bubbles finally stop coming up.If you do get more bubbles,
8) Start the car again, warm up and enjoy the heat with the system finally fully evacuated.
It seem the heater core/valve wants to trap air bubbles because there’s a low point in the lines between the heater core and the rest of the coolant system. After I finally figured it out the first time when the heat wouldn’t warm up after doing the flush, I ended up repeating for a rinse/fill and the final fill with the new radiator, and every single time, I had to vacuum fill, warm up the car first, cool and then repeat pulling vacuum 3 times before bubbles stopped coming up, at which point the heat would come on right away.
I tried the vacuum hold/foaming thing before starting the car so as not to wait for the cooldown, but no matter what it took running the car and then 3x vacuum purging to get all the air out.
Haven’t had a problem since, even driving the car hard on a warm day.
I think the heater lines and possibly the cylinder head just have high spots that hold a little air even after running the car for a while, and it seems like it doesn’t come out of the system even after running the car unless you pull vacuum and hold/wait.
Also, don’t be fooled - the stacked plate oil heat exchanger under the oil filter is a serious little unit and it is capable of pulling a decent amount of heat out of the oil, not just an oil warmer. I’ve used that heat exchanger style for work, and they work quite well.
The moral here is that the factory oil cooler pulls a lot of extra heat into the cooling system that the radiator has to deal with, and adding an external oil cooler will take some heat load off the radiator and reduce coolant temperatures.
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