How do you bleed a radiator?
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How do you bleed a radiator?
Last edited by TomCat39; 01-07-2017 at 08:38 PM.
#2
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Re: How do you bleed a radiator?
On Hondas with a bleed valve, you are only supposed to use it when filling the actual system. With a cold engine, you set the climate control to full hot (no fan), then open the bleed valve and pour coolant into the radiator until coolant flows steady out of the bleed valve. Next close the bleed valve and top off the radiator.
Now for the hard part.....burp all remaining air out of the system. This part is a long process of running the car for a LONG time without the radiator cap on. The best way to do this to use a spill-free funnel. It's only $20-25 on Amazon. Great tool and works on all Hondas. Getting all the air out takes a long time because the water pump turns big bubbles into tiny ones.
Eric the Car Guy did a great video detailing the entire process....
Now for the hard part.....burp all remaining air out of the system. This part is a long process of running the car for a LONG time without the radiator cap on. The best way to do this to use a spill-free funnel. It's only $20-25 on Amazon. Great tool and works on all Hondas. Getting all the air out takes a long time because the water pump turns big bubbles into tiny ones.
Eric the Car Guy did a great video detailing the entire process....
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Re: How do you bleed a radiator?
On Hondas with a bleed valve, you are only supposed to use it when filling the actual system. With a cold engine, you set the climate control to full hot (no fan), then open the bleed valve and pour coolant into the radiator until coolant flows steady out of the bleed valve. Next close the bleed valve and top off the radiator.
Now for the hard part.....burp all remaining air out of the system. This part is a long process of running the car for a LONG time without the radiator cap on. The best way to do this to use a spill-free funnel. It's only $20-25 on Amazon. Great tool and works on all Hondas. Getting all the air out takes a long time because the water pump turns big bubbles into tiny ones.
Eric the Car Guy did a great video detailing the entire process....
https://www.youtube.com/watch?v=zUpXgAJ1gjU
Now for the hard part.....burp all remaining air out of the system. This part is a long process of running the car for a LONG time without the radiator cap on. The best way to do this to use a spill-free funnel. It's only $20-25 on Amazon. Great tool and works on all Hondas. Getting all the air out takes a long time because the water pump turns big bubbles into tiny ones.
Eric the Car Guy did a great video detailing the entire process....
https://www.youtube.com/watch?v=zUpXgAJ1gjU
#4
Re: How do you bleed a radiator?
#5
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Re: How do you bleed a radiator?
I don't think b-series have bleed valves. I know B16 and B18C's don't. I think at some point Honda stopped using them cause my 04 Pilot and 05 TL don't have them either. Really the bleed valve is pointless cause you will still have trapped air inside, so burping the system is still mandatory. I don't bother with the bleed valve on my 89 CRX. I just went right to it with the spill-free-funnel. Took a while to get all the air out as usual. Had to get the radiator fan to come on twice.
BTW: I found another trick to finishing off the bleed process yesterday.... Once you are certain you have all the air out of the system with the funnel (radiator fan comes on a couple times + occasional reving + occasional squeezing of the upper hose, wait for the fan to kick on again. Whenever the fan kicks on, the coolant temp drops and the fluid shrinks back down. The moment the fan switches off, quickly plug the funnel, remove the adapters and install your radiator cap. Once the fan turns off, the coolant begins to swell again. This swelling ensures fluid pushes the air out of the reservoir tank hose (instead of sucking air back into the radiator).
The real trick is then topping off your reservoir without letting air back into the hose.
BTW: I found another trick to finishing off the bleed process yesterday.... Once you are certain you have all the air out of the system with the funnel (radiator fan comes on a couple times + occasional reving + occasional squeezing of the upper hose, wait for the fan to kick on again. Whenever the fan kicks on, the coolant temp drops and the fluid shrinks back down. The moment the fan switches off, quickly plug the funnel, remove the adapters and install your radiator cap. Once the fan turns off, the coolant begins to swell again. This swelling ensures fluid pushes the air out of the reservoir tank hose (instead of sucking air back into the radiator).
The real trick is then topping off your reservoir without letting air back into the hose.
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Re: How do you bleed a radiator?
Also code 43 would pop up if not fully warmed up.i haven't got a chance to get the front raised to properly bleed the coolant but once warming and bouncing idle comes back I would switch the heater settings and this seems to bring back the idle to steady.cluld this be a sign it needs to be bled better?another thing I tried was with the car running I unplugged my iacv and the car would die out..if that gives any help
#7
Re: How do you bleed a radiator?
Park on level ground wait until fully cold, take the radiator cap off. If the radiator is not full to the top you need to bleed again.
if it keeps getting a bubble of air, the head gasket is likely leaky, though you need to also rule out bad seals in the radiator cap and air leaks in the hose between the radiator and the white plastic tank.
if it keeps getting a bubble of air, the head gasket is likely leaky, though you need to also rule out bad seals in the radiator cap and air leaks in the hose between the radiator and the white plastic tank.
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Re: How do you bleed a radiator?
Don't think it's a leaky head gasket.wouldnt I be burning coolant or oil?..I'll check coolant again and try to flush
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#11
Re: How do you bleed a radiator?
The only symptom of a small leak from a cylinder to the coolant is what your car is doing-- coolant is displaced out of the radiator and engine leading to eventual overheating and a need to bleed the air out over and over.
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Re: How do you bleed a radiator?
so i do have a leak?i have no coolant or oil mixture tho?and your telling me that's why my coolant over flows with no bubbles?and I have to rebleed with front of car on stand or angle is that what your saying?how do I stop the leak?
#13
Re: How do you bleed a radiator?
Get as full as you can, then wait until cold. Squeeze the top radiator hose. If there is pressure in it, loosen the radiator cap to release then put cap back on. Start the engine, rev it, and keep squeezing the hose. You should not feel much pressure. If pressure builds up right away with the engine still cold, the head gasket is leaking. This can be confirmed with a block tester. The cure is to remove the head and replace the gasket. Do not try stop leak agents, they seldom work and can cause a lot of complications.
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Re: How do you bleed a radiator?
Get as full as you can, then wait until cold. Squeeze the top radiator hose. If there is pressure in it, loosen the radiator cap to release then put cap back on. Start the engine, rev it, and keep squeezing the hose. You should not feel much pressure. If pressure builds up right away with the engine still cold, the head gasket is leaking. This can be confirmed with a block tester. The cure is to remove the head and replace the gasket. Do not try stop leak agents, they seldom work and can cause a lot of complications.
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#21
Re: How do you bleed a radiator?
OK that's good. It doesn't absolutely mean the head gasket doesn't leak, it could still leak when hot or when the pressure in the engine is higher from actually driving rather than revving up in neutral.
Next would be to consider the reserve tank system. The connection from the tank to the radiator needs to be completely airtight so that the slight vacuum that forms as the engine cools down is able to draw coolant out of the tank and back into the radiator. Inspect the hose connections and both rubber seals in the radiator cap especially the top one.
Next would be to consider the reserve tank system. The connection from the tank to the radiator needs to be completely airtight so that the slight vacuum that forms as the engine cools down is able to draw coolant out of the tank and back into the radiator. Inspect the hose connections and both rubber seals in the radiator cap especially the top one.
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Re: How do you bleed a radiator?
When I open the rad cap and have it runnin coolant just over flows but when I take out the other end of t he resvoior cap coolant doesn't over flow..?
#24
Re: How do you bleed a radiator?
Does it overflow when cold? Running the engine cold with the cap off, there should be almost no action in the radiator. Bubbling or gushing out when cold usually means a head gasket leak.
Coolant expands when the engine heats up. That is why there is a reservoir tank. When the pressure in the system reaches the design point, the excess volume of coolant is supposed to move into the reservoir tank. Then it returns when the engine is off and it cools down. If it does not return and air enters instead, you have a bubble of air in the system which is not good.
Coolant expands when the engine heats up. That is why there is a reservoir tank. When the pressure in the system reaches the design point, the excess volume of coolant is supposed to move into the reservoir tank. Then it returns when the engine is off and it cools down. If it does not return and air enters instead, you have a bubble of air in the system which is not good.
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Re: How do you bleed a radiator?
Does it overflow when cold? Running the engine cold with the cap off, there should be almost no action in the radiator. Bubbling or gushing out when cold usually means a head gasket leak.
Coolant expands when the engine heats up. That is why there is a reservoir tank. When the pressure in the system reaches the design point, the excess volume of coolant is supposed to move into the reservoir tank. Then it returns when the engine is off and it cools down. If it does not return and air enters instead, you have a bubble of air in the system which is not good.
Coolant expands when the engine heats up. That is why there is a reservoir tank. When the pressure in the system reaches the design point, the excess volume of coolant is supposed to move into the reservoir tank. Then it returns when the engine is off and it cools down. If it does not return and air enters instead, you have a bubble of air in the system which is not good.