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Re: White Steam Shooting From Radiator Cap
Originally Posted by 310civicEX
i wouldnt trust the mechanic.. for my own piece of mind id go to autozone and have them look up the proper cap and sell it to ya.. might not fix it but you can rule out wrong cap.
I wouldn't trust an aftermarket cap especially when an OEM cap is less than a $10 difference.
I've never purchased a rad cap for a 7th gen but I have for a 6th gen. The first one I purchased was an aftermarket Stant brand and when tighten/installed it rocked back and forth too much for my liking so I purchased an OEM Honda cap from the local dealer and it fit much better with much less rocking. I matched the two up and noticed the difference was in the metal lip (shown in view 2) that curls under the top of the radiator opening to keep it tight. The OEM's lip is longer than the aftermarket's which makes it more stable and IMO seal better.
Last edited by Wankenstein; Oct 29, 2017 at 04:18 PM.
Update.
I filled the radiator back up with coolant, then I got a turkey baster and took out the excess coolant from the reservoir. So far, there was no smoke, but a slight leak of coolant can still be seen from the cap. This is after a 15 minute drive.
These are pictures of my radiator cap and radiator opening
I wouldn't trust an aftermarket cap especially when an OEM cap is less than a $10 difference.
I've never purchased a rad cap for a 7th gen but I have for a 6th gen. The first one I purchased was an aftermarket Stant brand and when tighten/installed it rocked back and forth too much for my liking so I purchased an OEM Honda cap from the local dealer and it fit much better with much less rocking. I matched the two up and noticed the difference was in the metal lip (shown in view 2) that curls under the top of the radiator opening to keep it tight. The OEM's lip is longer than the aftermarket's which makes it more stable and IMO seal better.
You know what, this cap does look like the original one that I had. And the lips are longer as well. Mine had a black covering on it, but I cannot seem to find one.
Or call local dealer for price.
You didn't give your car's year or model but all '01-'05 models most likely use the same cap and cap cover.
Longer lip is just OEM (Denso) vs. aftermarket and not OEM vs. OEM as there is only one type/length.
Or call local dealer for price.
You didn't give your car's year or model but all '01-'05 models most likely use the same cap and cap cover.
Longer lip is just OEM (Denso) vs. aftermarket and not OEM vs. OEM as there is only one type/length.
It's a 2002 Honda Civic EX
I need to look for OEM(DENSO)?
In your picture it’s clearly evident that the radiator is junk now.
Before you just replace it, you should trace down why your overheating else your just gonna pop that hose off again, and or create a super steam event again and ruin the next radiator.
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Re: White Steam Shooting From Radiator Cap
Not sure how long ago the OP purchased this car but it almost looks like someone (prior owner or mechanic) poured in a bottle of the Devil's Jizz at some point.
In your picture it’s clearly evident that the radiator is junk now.
Before you just replace it, you should trace down why your overheating else your just gonna pop that hose off again, and or create a super steam event again and ruin the next radiator.
In your experience, what would cause a Super Steam situation?
Water turns to steam aka boils at about 250 degrees in a pressurized coolant system as in a Honda.
Now if that steam is heated from the cylinders due too much air in the system or too little flow of coolant or cooling air, parts can be exposed to much higher temperatures than most people realize.
I have seen radiator caps steaming at over 400 degrees when owners drive the car till it stops and called us to tow it.
Water turns to steam aka boils at about 250 degrees in a pressurized coolant system as in a Honda.
Now if that steam is heated from the cylinders due too much air in the system or too little flow of coolant or cooling air, parts can be exposed to much higher temperatures than most people realize.
I have seen radiator caps steaming at over 400 degrees when owners drive the car till it stops and called us to tow it.
I see. I only drive it to work and back and each time before I crank it up, I put coolant back into the system. I see small amounts of steam, but it's starting to cool down here. I'm not sure if the cold air is making the heat from the cap visible.
Since the sealing surface in your radiator neck is gone, your system can not achieve good pressure and now your likely boiling at 212 which is normal driving range.
To to answer your main question, your seeing steam coming out because your radiator is perished and no longer letting the cap seal correctly.
Before you replace the radiator I suggest you do a leak down test to make sure your current head gasket is not leaking.
Seems auto parts places let you use the tool for free and you just spend 20 for the fluid.
Sure the colder weather will help if you have bad airflow, but does little to help if every burn of the spark plug is pushing hot exhust into your cooling system.
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Re: White Steam Shooting From Radiator Cap
Originally Posted by Slumpertcivic
Before you replace the radiator I suggest you do a leak down test to make sure your current head gasket is not leaking.
Seems auto parts places let you use the tool for free and you just spend 20 for the fluid.
What you're describing is termed a Block Test: blue fluid turns greeen or yellow if it detects exhaust emissions in coolant. It's only a definitive test if the blue tests fluid changes color. Can pass this test yet still have a head-gasket breach.
A leakdown test is air injected into the cylinders at TDC. Can use a leakdown tester tool that shows leak percentage or specifically to determine a head gasket breach use straight shop air at 125 psi, open radiator cap and look for bubbles in radiator. Bubbles equal breach.
Last edited by Wankenstein; Oct 31, 2017 at 03:51 PM.
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Re: White Steam Shooting From Radiator Cap
Originally Posted by KaptainKendrick
So what are some steps that can be taken to remove air from the cooling system on that car?
I've probably written (below) this five times already this month..lol
* Put front of car on jackstands as high as possible
* Set climate control to max heat, recirculate mode and fan "Off"
* Remove radiator cap (optional to insert a funnel into radiator neck to prevent overflow)
* Start engine and let idle until radiator fan engages twice (roughly 20 minutes). Bubbles should get smaller and almost non existent when bled properly. Add coolant to keep the level in the radiator filled during bleeding procedure.
* Turn off engine, cover radiator neck with a rag or install cap.
* Let engine cool for several hours or overnight and check radiator and reservoir levels. If radiator level is down then fill coolant to the top. Only filll the reservoir half way between "min" and "max".
* Check both levels everyday for the next 5 days or so to ensure it's not losing coolant.
I changed the radiator and cap on my 02 Civic Ex. I am going to flush the system, so I added coolant flush and distilled water to the system and reservoir. I drove it to work so that it could go all the way thought the system. When I parked, I noticed that the coolant reservoir was boiling over, but not the radiator cap. What could be going on?
If you think a good mechanic is expensive, try hiring a bad one
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Re: White Steam Shooting From Radiator Cap
Originally Posted by KaptainKendrick
Update:
I changed the radiator and cap on my 02 Civic Ex. I am going to flush the system, so I added coolant flush and distilled water to the system and reservoir. I drove it to work so that it could go all the way thought the system. When I parked, I noticed that the coolant reservoir was boiling over, but not the radiator cap. What could be going on?
Word:
Originally Posted by ezone
Next question to figure out:
You said the head gasket was already replaced.
Has that been damaged now? A single overheat event can ruin all that work.
