How did I mess up a coolant flush?
11-11-2010, 03:38 PM
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How did I mess up a coolant flush?
Ok it's first snowfall here in Canada so I thought I'd flush the coolant on my DA9. I drain the coolant, fill with distilled water, run the engine until the fan kicks in, and drain. It worked; coolant came out blue, it had mixed. After a few times the water ran clear, so I filled it up with the new stuff, which was red. This time when I loosened the drain, cold fluid trickled out which was still dark red so I didn't drain. I felt the lower rad hose, it was cold as well so I thought it was just a stuck thermostat. When I pulled off the hose from the thermo housing to just have a look, a small ammount of hot, light red coolant spilled out, meaning coolant had made it past the thermostat, but somehow not down the rest of the hose.
I put the hose back on and decided to just finish the job(or try to). My car ran for a half hour with the rad cap off and the coolant level did not drop once, so I threw the cap back on. I opened the bleed screw but no air or coolant came out unless I squeezed on the upper hose(which was hot and had been the entire time), meaning there is a butt load of air in my engine. I would assume, that ammount of air would surely cause the engine to overheat but the whole time my temp needle was exactly where it always was; just touching the squiggley water line on the gauge. It wasnt smart to do but I drove around the block and opened the rad cap... no pressure, but coolant was right at the top, and overflow was max too.
Is there something wrong with my car, or did I just somehow screw up general maintenance?
I put the hose back on and decided to just finish the job(or try to). My car ran for a half hour with the rad cap off and the coolant level did not drop once, so I threw the cap back on. I opened the bleed screw but no air or coolant came out unless I squeezed on the upper hose(which was hot and had been the entire time), meaning there is a butt load of air in my engine. I would assume, that ammount of air would surely cause the engine to overheat but the whole time my temp needle was exactly where it always was; just touching the squiggley water line on the gauge. It wasnt smart to do but I drove around the block and opened the rad cap... no pressure, but coolant was right at the top, and overflow was max too.
Is there something wrong with my car, or did I just somehow screw up general maintenance?
11-11-2010, 04:31 PM
#2
Re: How did I mess up a coolant flush?
man. i don't know where people get the idea that a cooler lower rad hose is something to worry about. it is a normal occurance. the lower rad hose is where the cooler fluid exits the rad.
however, if your reservoir is filling up and not cycling back into the rad, i'd suspect a faulty rad cap
however, if your reservoir is filling up and not cycling back into the rad, i'd suspect a faulty rad cap
11-11-2010, 04:35 PM
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Re: How did I mess up a coolant flush?
the el crapitan stikes again lol
https://honda-tech.com/forums/acura-integra-6/91-integra-overheating-2842009/
https://honda-tech.com/forums/acura-integra-6/91-integra-overheating-2842009/
11-11-2010, 04:51 PM
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Re: How did I mess up a coolant flush?
the lower hose wasnt cold because of coolant it was cold because there was nothing in it. it goes from the bottom of the rad to the thermostat housing, so doesn't that mean hot coolant comes from the thermo, down the hose?
11-11-2010, 04:58 PM
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Re: How did I mess up a coolant flush?
It happened because you didn't follow the proper flush procedure. You need to drain the radiator AND drain the block (bolt behind exhaust manifold), and then you need to remove the thermostat, put the housing and hose back on, then flush water through the system with the garden hose. Drain everything again, then put the thermostat back in and fill the system with 50/50.
See this post: https://honda-tech.com/forums/showpo...46&postcount=7
And make sure you do it with the heater temperature slider set to full Hot so that the heater core will also get flushed out.
See this post: https://honda-tech.com/forums/showpo...46&postcount=7
And make sure you do it with the heater temperature slider set to full Hot so that the heater core will also get flushed out.
First, set the climate control temp slider to HOT. Drain the coolant from the radiator thru the drain plug, then disconnect the lower radiator hose from the radiator to let coolant drain out of there. Put the radiator hose back on.
Next locate the coolant drain bolt on the engine block. On B and D series engines it's behind the exhaust manifold/header, slighly towards the tranny end of the block. It's a BIG bolt, 19mm I believe, hard to miss. Remove that. Have a large container ready, because it will come GUSHING out. After it finishes draining, replace the bolt.
Now comes the tricky part. Remove the lower radiator hose and coolant temp sensor from the thermostat housing and then remove the housing w/ the thermostat. One of the housing bolts is pretty difficult to get to, so have some wrenches or a swivel socket joint handy (I can't remember what I used). Put the housing back in w/o the thermostat and reconnect the lower hose.
Now remove the upper radiator hose from the radiator and point it towards your drain bucket. Stick the garden hose into the top of the radiator where the upper hose connects and run the water. The remaining coolant in the block will be flushed out through the upper radiator hose. Keep the water running until the fluid coming out of the upper hose is clear.
Now remove the block drain bolt again to drain any remaining water in the block. Reinstall the thermostat and coolant temp sensor and all hoses etc. Fill the radiator w/ a 50/50 mixture of coolant and water (Honda pre-mixed, or Prestone and distilled water, do NOT use Xerex or Peak as it contains silicates which can damage the radiator). You will have to pour it in SLOWLY as it tends to bubble up and spurt out of the filler hole while you pour it in.
Once the coolant reaches the base of the filler neck, run the engine until it fully warms up and the radiator fan comes on. The upper radiator hose will also become hot. After this the coolant level in the radiator should have dropped since the thermostat opens and allows coolant into the block and the heater core. Shut off the engine, and continue to fill the radiator until it get to the base of the filler neck.
Locate the bleed bolt where the upper radiator hose attaches to the cylinder head (OBD I vehicles only). Loosen this bolt and let the coolant flow out until it flows out steady w/o bubbles. Squeeze the upper radiator hose to help get any remaining air out of the system. Continue squeezing the upper hose until no more bubbles come up at the base of the filler neck, and continue to add coolant as necessary to keep the level at the base of the filler neck.
Remove and wash out the coolant overflow tank, fill it to the proper level, and you're done!
Wow I didn't know it would be this long, but that's how it's done.
If I've left out or messed up any steps, please chime in. 
Next locate the coolant drain bolt on the engine block. On B and D series engines it's behind the exhaust manifold/header, slighly towards the tranny end of the block. It's a BIG bolt, 19mm I believe, hard to miss. Remove that. Have a large container ready, because it will come GUSHING out. After it finishes draining, replace the bolt.
Now comes the tricky part. Remove the lower radiator hose and coolant temp sensor from the thermostat housing and then remove the housing w/ the thermostat. One of the housing bolts is pretty difficult to get to, so have some wrenches or a swivel socket joint handy (I can't remember what I used). Put the housing back in w/o the thermostat and reconnect the lower hose.
Now remove the upper radiator hose from the radiator and point it towards your drain bucket. Stick the garden hose into the top of the radiator where the upper hose connects and run the water. The remaining coolant in the block will be flushed out through the upper radiator hose. Keep the water running until the fluid coming out of the upper hose is clear.
Now remove the block drain bolt again to drain any remaining water in the block. Reinstall the thermostat and coolant temp sensor and all hoses etc. Fill the radiator w/ a 50/50 mixture of coolant and water (Honda pre-mixed, or Prestone and distilled water, do NOT use Xerex or Peak as it contains silicates which can damage the radiator). You will have to pour it in SLOWLY as it tends to bubble up and spurt out of the filler hole while you pour it in.
Once the coolant reaches the base of the filler neck, run the engine until it fully warms up and the radiator fan comes on. The upper radiator hose will also become hot. After this the coolant level in the radiator should have dropped since the thermostat opens and allows coolant into the block and the heater core. Shut off the engine, and continue to fill the radiator until it get to the base of the filler neck.
Locate the bleed bolt where the upper radiator hose attaches to the cylinder head (OBD I vehicles only). Loosen this bolt and let the coolant flow out until it flows out steady w/o bubbles. Squeeze the upper radiator hose to help get any remaining air out of the system. Continue squeezing the upper hose until no more bubbles come up at the base of the filler neck, and continue to add coolant as necessary to keep the level at the base of the filler neck.
Remove and wash out the coolant overflow tank, fill it to the proper level, and you're done!
Wow I didn't know it would be this long, but that's how it's done.
If I've left out or messed up any steps, please chime in.
11-11-2010, 05:08 PM
#6
Re: How did I mess up a coolant flush?
i think you may be a bit confused. don't worry about the cool lower rad hose. just re-flush the system using patrick's instructions
11-11-2010, 05:20 PM
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11-11-2010, 07:09 PM
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Re: How did I mess up a coolant flush?
The left end of #11 lower rad hose in this pic:
attaches to #8/#9 thermostat housing in this pic, on the back side of the head:
The upper rad hose attaches to #10 on the passenger side of the head, under the distributor cap.
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