I have a bunch of gunk in my cooling system. I’ve owned my 230k 2003 LX for several years but have no idea what the PO did. About 2 years ago I couldn't get any heat in the winter and had a well-rated indie shop in Berkeley, CA replace the the heater core and do the water pump/timing belt. The heater worked great immediately after, but I think the shop was a little light on the coolant flush for their own particular reasons. After, I paid a Lexus dealership to flush the coolant but they left it 1/2 gallon empty and I still saw a lot of "powder" in the coolant under the radiator cap. Solids settled out when I took a sample.
This winter, up in Portland, OR, the heater stopped blowing hot air and I had a 3rd shop confirm its a clogged heater core. Paid them $350 to do a really thorough reverse flush with no promises, and the inside air temp increased maybe 10deg, but still pretty cool.
So... I just reverse flushed my heater core myself with a hose and cleared out chunks of brown gunk. The flow rate immediately went from low to high but even after 30 minutes of flowing hose water I still saw chunks flowing out. I followed this Heater Core Flushing thread by @izzyandsue in 80 series forums, except I didn't really need the CLR. Just pulsing the hose pressure using a valve would clear out more chunks of gunk ... it literally looks like dense brown pond algae.
The heater blows really hot!!! ... for now. I think I have the heater core pretty clean but want to do a really thorough flush of the whole system because I can only imagine this gunk is everywhere.
I've read the following threads that give good instructions to find the 3 drain plugs:
Here's a sample of the coolant from top of radiator as it sits before solids have settled out
Here are photos of some of the crap I drained out of the heater core after settling for a day.
Note that this is after
This winter, up in Portland, OR, the heater stopped blowing hot air and I had a 3rd shop confirm its a clogged heater core. Paid them $350 to do a really thorough reverse flush with no promises, and the inside air temp increased maybe 10deg, but still pretty cool.
So... I just reverse flushed my heater core myself with a hose and cleared out chunks of brown gunk. The flow rate immediately went from low to high but even after 30 minutes of flowing hose water I still saw chunks flowing out. I followed this Heater Core Flushing thread by @izzyandsue in 80 series forums, except I didn't really need the CLR. Just pulsing the hose pressure using a valve would clear out more chunks of gunk ... it literally looks like dense brown pond algae.
The heater blows really hot!!! ... for now. I think I have the heater core pretty clean but want to do a really thorough flush of the whole system because I can only imagine this gunk is everywhere.
I've read the following threads that give good instructions to find the 3 drain plugs:
- Another Radiator Flush Question
- Radiator Flush/Coolant Drain DIY @newbee mechanic thanks for the pics
- Heater Core Flush
Here's a sample of the coolant from top of radiator as it sits before solids have settled out
Here are photos of some of the crap I drained out of the heater core after settling for a day.
Note that this is after
- ~$2500 water-pump, timing belt & alternator @ shop A
- ~$2500 heater core @ shop A
- ~$150 coolant flush @ shop B
- ~$350 coolant flush / heater core backflow @ shop C
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