jslt
Member
Hey everyone,
I've been lurking here for years to help keep my 2000 Expedition running and have always appreciated all the insight, but never had to cause to create an account. I've finally got a question that I can't answer with searching so here I am.
TLDR: Lots of coolant flushing, still getting rusty flakes. Worried about killing new heater cores if I call it good.
I've had this car since 2016. As far as I can remember, the heater has never actually worked. In 2018 I had the coolant flushed by a mechanic and they told me that the heater core was probably clogged and would eventually need to be replaced. I held off on the job because of the price. Finally, this year, I got tired of being cold and decided to try and fix it myself.
So here is where I am at. I dropped the dash and pulled the front heater core. It was definitely full of gunk. In the process, I realized that a) the coolant was pretty rusty and b) this car also has a rear heater core. I got the rear core out too and it was full of rust flakes and also totally shot.
I set up a bypass for each heater core and have been proceeding to flush system. I pulled the thermostat out and got the driver's side block drain out as well. I have done two separate chemical flushes and spent literal days of doing garden hose flushes, using the radiator drain, the block drain, and the rear heater hoses in various combinations.
My question/problem is this: while most of the crap is out of the system and the water runs clear, if I flush the water into a 5 gallon bucket and let it settle, I can still see small flakes of rust. Less, but they are still there. I pulled the old heater hoses off and looked inside the engine outlet and I can see that there is still some rust caked on the walls. I think I will forever be getting some flaking each time I do a flush, no matter how many times I do it. I've probably used 100 gallons of water at this point. The photo of the heater old hose is after I've done all this flushing (I scraped the sides with the screwdriver to show how much crap is still caked on).
At this point, I can only think of a few courses of action.
1) Just install the new heater cores, put it all back together, fill with coolant and drive it. Do more frequent coolant flushes for the next several years. Maybe try and install a coolant filter?
2) Leave the heater core bypasses, put it all back together, fill with distilled water and drive it around for a bit. Dump the water and repeat driving/flushing until no flakes/rust water is coming out, then install the new heater cores, etc.
3) Leave the heater core bypasses and try a citric acid flush(es), followed by water flushes, repeat until no flakes/rust water is coming out, then install the new heater cores, etc.
Any advice or insight would be appreicated. After all this work, my main fear is killing the brand new heater cores I went to all this trouble to install. The car has been running great and does not over heat, so the radiator and water pump seem fine.
Sorry for the long post!
I've been lurking here for years to help keep my 2000 Expedition running and have always appreciated all the insight, but never had to cause to create an account. I've finally got a question that I can't answer with searching so here I am.
TLDR: Lots of coolant flushing, still getting rusty flakes. Worried about killing new heater cores if I call it good.
I've had this car since 2016. As far as I can remember, the heater has never actually worked. In 2018 I had the coolant flushed by a mechanic and they told me that the heater core was probably clogged and would eventually need to be replaced. I held off on the job because of the price. Finally, this year, I got tired of being cold and decided to try and fix it myself.
So here is where I am at. I dropped the dash and pulled the front heater core. It was definitely full of gunk. In the process, I realized that a) the coolant was pretty rusty and b) this car also has a rear heater core. I got the rear core out too and it was full of rust flakes and also totally shot.
I set up a bypass for each heater core and have been proceeding to flush system. I pulled the thermostat out and got the driver's side block drain out as well. I have done two separate chemical flushes and spent literal days of doing garden hose flushes, using the radiator drain, the block drain, and the rear heater hoses in various combinations.
My question/problem is this: while most of the crap is out of the system and the water runs clear, if I flush the water into a 5 gallon bucket and let it settle, I can still see small flakes of rust. Less, but they are still there. I pulled the old heater hoses off and looked inside the engine outlet and I can see that there is still some rust caked on the walls. I think I will forever be getting some flaking each time I do a flush, no matter how many times I do it. I've probably used 100 gallons of water at this point. The photo of the heater old hose is after I've done all this flushing (I scraped the sides with the screwdriver to show how much crap is still caked on).
At this point, I can only think of a few courses of action.
1) Just install the new heater cores, put it all back together, fill with coolant and drive it. Do more frequent coolant flushes for the next several years. Maybe try and install a coolant filter?
2) Leave the heater core bypasses, put it all back together, fill with distilled water and drive it around for a bit. Dump the water and repeat driving/flushing until no flakes/rust water is coming out, then install the new heater cores, etc.
3) Leave the heater core bypasses and try a citric acid flush(es), followed by water flushes, repeat until no flakes/rust water is coming out, then install the new heater cores, etc.
Any advice or insight would be appreicated. After all this work, my main fear is killing the brand new heater cores I went to all this trouble to install. The car has been running great and does not over heat, so the radiator and water pump seem fine.
Sorry for the long post!
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