Koyo radiator, what cap to use
#1
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Koyo radiator, what cap to use
Replaced leaky oem with a nice koyo direct replacement unit. Original oem has been in use for a very long time and I've read on here they have a service life of about 30kmi. Should I just replace with another oem? Looks like a lot of people use high pressure aftermarket, but mostly for looks...not the path I'd like to take. Koyo brand caps are 1.3bar which I think is too high. Does anyone know what the oem cap pressure is? 0.9bar/13psi or 1.1bar/16psi? Service manual doesnt say what its pressure is, just that it should test between 14-18psi (12psi min) before releasing...
Would like to know what most people are using, esp if you have a koyo rad too. My car is an avg bolt on making about 380whp. Avg driver too, no extreme heat conditions...thanks
Would like to know what most people are using, esp if you have a koyo rad too. My car is an avg bolt on making about 380whp. Avg driver too, no extreme heat conditions...thanks
#2
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been using the stock one for 75k miles. id stick with stock
Replaced leaky oem with a nice koyo direct replacement unit. Original oem has been in use for a very long time and I've read on here they have a service life of about 30kmi. Should I just replace with another oem? Looks like a lot of people use high pressure aftermarket, but mostly for looks...not the path I'd like to take. Koyo brand caps are 1.3bar which I think is too high. Does anyone know what the oem cap pressure is? 0.9bar/13psi or 1.1bar/16psi? Service manual doesnt say what its pressure is, just that it should test between 14-18psi (12psi min) before releasing...
Would like to know what most people are using, esp if you have a koyo rad too. My car is an avg bolt on making about 380whp. Avg driver too, no extreme heat conditions...thanks
Would like to know what most people are using, esp if you have a koyo rad too. My car is an avg bolt on making about 380whp. Avg driver too, no extreme heat conditions...thanks
#7
FYI, OEM cap is about a half mm too wide on the spring loaded portion, and will scrape up the filler neck over time. The Koyo cap is a little narrower and fits properly, so definitely use a Koyo cap with the Koyo radiator.
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#8
I run the koyo direct fit full sized rad on my 2003 with the OEM cap. Works great.... Only problem with my set up is it's a little wider than the oem one so my wastegate dump tube vibrates against it and gets a bit noisy.
#11
Do you guys get a little bit of a coolant smell around the Koyo radiator/cap? I've tried a couple of Koyo caps, and get a tiny bit of a smell/leak that I don't get if I use an OEM cap. As mentioned above, the OEM cap will scrape up the inside of the filler neck, so I'm looking for another one.
#12
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Do you guys get a little bit of a coolant smell around the Koyo radiator/cap? I've tried a couple of Koyo caps, and get a tiny bit of a smell/leak that I don't get if I use an OEM cap. As mentioned above, the OEM cap will scrape up the inside of the filler neck, so I'm looking for another one.
#13
That's exactly what I'm trying to solve. I don't get any leak, but I can smell coolant pretty much anytime the car is run for an extended period. Very faint, and most people don't notice. No leaks anywhere, no change in level, reservoir stays at the same level. I've been running oem this whole time. Was hoping that a koyo cap would make a better fit...
I also find the smell very faint, and nobody else can smell it, but I have a very sensitive nose and it clearly is smelling. I'm not sure if my reservoir tank drop at all, it MIGHT be like 1mm over the course of a month, but it's definitely not an obvious amount.
The main problem though is that the filler neck is 1mm smaller than OEM, and pretty much every radiator cap I've been able to find will scrape up the inside lip of the neck and not provide a good seal in the radiator. The Koyo cap is 1mm smaller in diameter on that little metal valve in the middle.