Experienced civic owner needs help with random overheats
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From: Land of JB Pritzker
Re: Experienced civic owner needs help with random overheats
Pix uploaded.
so today i was trying to catch another issue on camera and i saw the temp gauge slowly start to creep, and with the hood open i could hear the fan had cycled on to try to bring the temp down.
Hysterically Calm
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Re: Experienced civic owner needs help with random overheats
The predicament here is that the radiator cap isnt something i can buy alone, the vendor doesn't have one. I bought the radiator off ebay years and years ago when i was living paycheck to paycheck, and i messaged the vendor recently to see if he would sell me just a cap but he said in broken english it's not possible. OEM honda cap doesn't fit on the throat either. The only way I could replace the cap is to put an OEM radiator back in. I'll jump the fan though and see if the problem recurs before going to that step. OEM radiator can be had for like 30 bucks on rockauto so I'm not too concerned, but I don't want to replace it if its not the problem.
Took me awhile to find the cap but once you know the proper year, you can ask any parts store for the Stant cap for that year and get the right cap for your alternate sized mouth radiator.
Yep seeing your picture it's an older civic cap, not the 92-95.
Re: Experienced civic owner needs help with random overheats
There are only two types of Honda radiator caps. If your 92+ cap with square ears doesn't fit, try the older style with the round ears (88-91 Civic works). The part number doesn't matter cause they are all the same (have the same spring pressure).
The thing I don't like about this style of cap is that it requires vacuum in the cooling system (from shrinking fluid) to overcome a secondary spring before drawing coolant back into the radiator. The newer square-ear cap has no secondary spring so the system never pulls vacuum. It's a better design (at least for a street car).
The thing I don't like about this style of cap is that it requires vacuum in the cooling system (from shrinking fluid) to overcome a secondary spring before drawing coolant back into the radiator. The newer square-ear cap has no secondary spring so the system never pulls vacuum. It's a better design (at least for a street car).
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Joined: Feb 2015
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From: Land of JB Pritzker
Re: Experienced civic owner needs help with random overheats
There are only two types of Honda radiator caps. If your 92+ cap with square ears doesn't fit, try the older style with the round ears (88-91 Civic works). The part number doesn't matter cause they are all the same (have the same spring pressure).
The thing I don't like about this style of cap is that it requires vacuum in the cooling system (from shrinking fluid) to overcome a secondary spring before drawing coolant back into the radiator. The newer square-ear cap has no secondary spring so the system never pulls vacuum. It's a better design (at least for a street car).
The thing I don't like about this style of cap is that it requires vacuum in the cooling system (from shrinking fluid) to overcome a secondary spring before drawing coolant back into the radiator. The newer square-ear cap has no secondary spring so the system never pulls vacuum. It's a better design (at least for a street car).
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From: Land of JB Pritzker
Re: Experienced civic owner needs help with random overheats
Did you change the radiator cap and check the connection to the plastic tank? Have you been checking that the radiator stays full?
Jump the fan switch on the thermostat housing to make the fan run all the time the key is on. Test drive like that. If it still overheats it is not the fan. The fan is switched by the temperature of coolant leaving the radiator. If there is no flow through the radiator, the engine can overheat but the fan stays off.
Jump the fan switch on the thermostat housing to make the fan run all the time the key is on. Test drive like that. If it still overheats it is not the fan. The fan is switched by the temperature of coolant leaving the radiator. If there is no flow through the radiator, the engine can overheat but the fan stays off.
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Re: Experienced civic owner needs help with random overheats
I also found a older civic caps of this style but none were 1.1bar / 16lbs
A non full radiator and unchanging overflow level are typical bad radiator cap behavior. The cap needs to be sealed to pull from the overflow, the top seal at least.
A non full radiator and unchanging overflow level are typical bad radiator cap behavior. The cap needs to be sealed to pull from the overflow, the top seal at least.
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Re: Experienced civic owner needs help with random overheats
Re: Experienced civic owner needs help with random overheats
You can still get the Honda one for between $13 and $20.... 19045-PR3-004..... This OEM part is made by Toyo so you may be able to get a basic Toyo radiator cap for cheaper online. t's also 1.1 bar.
https://www.oemacuraparts.com/auto-p...tor-denso-scat
https://www.oemacuraparts.com/auto-p...tor-denso-scat
Re: Experienced civic owner needs help with random overheats
Woah, I didn't know this but you can get one from a CBR in decorative black (probably have to get it from a motorcycle dealer)....
GENUINE HONDA RADIATOR CAP
19045-MZ1-621
GENUINE HONDA RADIATOR CAP
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