Heater core flush

If you don’t have a hose pick, you can make one by dulling the sharp point down on a regular pick.
I use a belt sander. I did have a dedicated hose pick. Don’t know where it went, I didn’t want to pay for another one.

 

I bought these cheapos at harbor freight. They work pretty good including my heater hoses.



I’ve done the heater core flush only without flushing the whole system. I got aggressive with CLR and didn’t want that through the engine. I caught all fluid and it had no solid particles. I maintain that in very cold weather (30 or lower) the water pump doesn’t have the capacity to blow hot air at idle with the fan on full. I’ve done EVERYTHING (thermostat, air bubbles, no pinched hoses) except replace a water pump. Doubt that’s it because they have metal blades and wouldn’t wear.

 

I don't know about that. Mine even at 20 degrees after the truck is warmed up it will run you out of the cab if you run it on high heat. ( Access Cab )

 

Same with crew cab, at 12 degrees just last week

 

I wish it was mine. At 3/4 or less it will be hot. On high after idling for 5 min it’s just warmish. I’ve timed the flow from a raised bucket through the heater core and again just through the hose. Both are within 3 sec/gallon.

 

I wish. Driving mine will poach an egg. At 500rpm idle it will cool down only when fan is on high.

 

That’s a pretty low idle speed. Even if in D

 

Just a guess. Maybe just a hair above halfway to 1k. Yes, mostly waiting to get on the freeway on a metered ramp in D.

 

Your tach needle may just be off

 

Back to the heater core hose removal....

Read everything b_r_o said.

Hose tools for sure, but in some cases I find it's easier just to slit the hoses with a single edge razor blade every 90 degrees and peel off. Clean up the pipe gently with light grade sand paper. Replace the hoses. If you're flushing the core, chances are the beast has got some miles/years on her.
jimmyh mentioned that flushing gets the entire system and I won't argue with that. Remember if you really want to go to the trouble of flushing you need to first remove the thermostat.
Flushing may or may not get all of the sediment out. As stated earlier, it settles in the bottom and some of it could remain suspended no matter how much water passes thru it. I would flush until you see clean water exiting and call it a day as far as cleaning the core goes.
Some worry about ending up with a diluted coolant solution if flushing the core. It's now full of water vs. coolant/water. If this concerns you, hook up an L-funnel or length of hose to the inlet side of the core. Hook up a length of hose to the outlet side and place the other end below in a catch pan. Start pouring in your coolant of choice into the inlet side until you see it coming out the outlet. Install new heater hoses and use the same type of clamps the mfg. put on the vehicle.

The best way to avoid a plugged heater core is to drain and flush the sytem/replace coolant often. Toyota says 5 yrs/100K. I change coolant every 3 yrs. Change yours whenever you like.

 

Not sure why the heater core is being blamed when there's an extremely high likelihood it's a blend door problem.

 

Thanks to all TW for the help.........ended up cutting the little elbow hose (the one that wouldn’t come off) and replaced it (NAPA$14), and flushing heater core ($9 hose from HD)...then paying 3rd party shop for professional coolant flush....(with chemicals and lubricants)
End result, Beautiful pink coolant good for 100k, and great HEAT, just in time for Snow in Houston......

 

First mechanic said, "defiinitely a heater core", and would need 2 days to tear apart my truck, ALL for the low price of $1100.00.
Now diagnosed with a bad heater core, I looked on here, WAIT!! I could Maybe flush it, which I did a dozen times w/CLR & Vinegar(seperately), water & low pressure air & vacuum. No Go So I did it all again the next day. Next, Elevated the front on jack stands, bled the system( I think). No Heat Finally, I make and appointment with a local radiator specialist. Hopeful that he will do my heater core for less than the other guys $1100. Fingers Crossed!
-They do a $90 diagnostic...

-I had a Blend Door issue. Cheap fix, $216.00 (inc. diagnostic)

Fullboogie called it right!

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