OVERHEATING!!! Help

[MR-VTEC]

hey guys,

i got a H22a in my civic and was using a prelude radiator but i changed it over to a KOYO aluminium radiator and ever since then i have had problems.

My car is running exactly 10 degrees hotter no matter whether on the highway or in traffic, it runs at 98 degrees:thumbdwn: . Also once the car has heated up it is pushing coolant into the overflow.

i have installed a switch so i can control my radiator fan in cabin or so i can run it constantly once the car has warmed up( i run the fan constantly once the car is warmed). i have also purchased a cusco 1.3bar radiator cap. i have flushed and bled the system.

i just cant seems to get the temperature any lower:confused:. i want to get the temp back to around the 85-88 degree mark where it used to be.

obviously it has something to do with the radiator as i had no problems before i changed them.

anyone got any ideas or suggestions.

[SKREMN]

why did you change radiators?
is the new radiator the same capacity as the old one?
maybe the radiator is shit and hasnt got good flow?

[egSi]

im guess ur thermostat is all good? i just swapped in a thicker alloy radiator + flushed system and all is good.

ur radiator come with any warnings etc? mine said no mixing coolant and no akaline coolants etc.

btw my eg>yours :p ;)

[Weq]

im guessing u whiched from a full size to a half size radiator? i have heard some theorys around that having a half size without anything next to it will cause air to flow around it instead of into the fins.... but thats just a thoery..

my guess is there are some bubbles in the system.. what kind iof overflow is it - is it hot as hell? does the collant look fresh in the overflow bottle, or off coloured.

[MR-VTEC]

why did you change radiators?
is the new radiator the same capacity as the old one?
maybe the radiator is shit and hasnt got good flow?.

I changed radiators because im am currently turboing the car and the compressor side of the turbo didn't fit with the old radiator so i had to go back to a civic half size raidator. This is why i got a Koyo radiator as it is a lot larger in capacity than the civic one but is still only a half size one.


im guess ur thermostat is all good? i just swapped in a thicker alloy radiator + flushed system and all is good.

ur radiator come with any warnings etc? mine said no mixing coolant and no akaline coolants etc.

btw my eg>yours :p ;).

yes, well there were no problems prior to the radiator change and it isnt really displaying the symptoms of a bad thermostat but i will change it anyway.

nah no warnings, but i didnt mix coolants anyway.

yes we have to catch up soon. you, andy and i have to go out for a cruise sometime soon and put some of your photography skills to work:thumbsup:


im guessing u whiched from a full size to a half size radiator? i have heard some theorys around that having a half size without anything next to it will cause air to flow around it instead of into the fins.... but thats just a thoery..

my guess is there are some bubbles in the system.. what kind iof overflow is it - is it hot as hell? does the collant look fresh in the overflow bottle, or off coloured.

Yes, i swicthed to a half size (more explained above).

The overflow is hot. Yes the coolant looks fresh, no discolouration whatsoever.

[iamhappy46]

Airflow, try and get a plate made up to block the air from finding the easier path past the radiator. Same theory as an intercooler, if the air can flow under the car or over the bonnet, then the intercooler ends up with heat soak.

If you have ever seen a Suzuki swift GTi, they have a metal panel on the drivers side for this exact reason.

Either way, good luck with it

[SKREMN]

i swoped my stock radiator to a smaller civic size but thicker custom radiator
I noticed the car sat a little hotter then normal
about 2mm more on the guage thats all

[MR-VTEC]

Airflow, try and get a plate made up to block the air from finding the easier path past the radiator. Same theory as an intercooler, if the air can flow under the car or over the bonnet, then the intercooler ends up with heat soak.

If you have ever seen a Suzuki swift GTi, they have a metal panel on the drivers side for this exact reason.

Either way, good luck with it

because of space restraints the fan is located on the front of the radiator, this too could prove to be an air flow problem, although it is run all the time.

i too think it is an air flow problem as this radiator has half the frontal surface area and the fan is far from flowing the required air in my opinion

[MR-VTEC]

i swoped my stock radiator to a smaller civic size but thicker custom radiator
I noticed the car sat a little hotter then normal
about 2mm more on the guage thats all

what guage are you reading your temp off?

my factory temp guage has not changed at all since the radiator swap?

i have a separate digital water temp guage and that is why i have noticed the 10 degree difference

[SKREMN]

i'm using the stock guage in my JDM cluster
Before it used to sit just before the picture of the thermo now it sits on the edge of it

[ECU-MAN]

maybe your new radiator is rooted, just kidding

was it a new radiator, eliminating cjanced of it having a few blocked cores

could be the charicteristics of the new setup, try changing to a cooler thermostat.

[iamhappy46]

Did you happen to wire the radiator fan to run in reverse now that it is located in front of radiator?? Once the fan is turned on, make sure you can feel the air being blown into the engine bay not towards the bumper or otherwise, it will not be very effective at all.

[fly_vti]

is a CTR radiator better then the normal civic ones? if it is try them, they are little. or just get a radiator that is designed to be a replacment for your car and is approved

[iamhappy46]

CTR radiator has smaller radiator hose outlets so I doubt it can be used on the H22a.

[barefootbonzai]

CTR radiator has smaller radiator hose outlets so I doubt it can be used on the H22a.

Don't think you're right with that. We are using vtir civic raditors on the H.

[MR-VTEC]

Did you happen to wire the radiator fan to run in reverse now that it is located in front of radiator?? Once the fan is turned on, make sure you can feel the air being blown into the engine bay not towards the bumper or otherwise, it will not be very effective at all.

the fan is wired correctly;)

[MR-VTEC]

is a CTR radiator better then the normal civic ones? if it is try them, they are little. or just get a radiator that is designed to be a replacment for your car and is approved

the koyo radiator is a replacement for the factory item:rolleyes:

[jdmTYPE R]

alloy radiator tends to heat up quick for street driving..but for track it will cool down quicker as airflow throw constant i had a koyo radiator in my previous car and i had the problem with it heating up quick on street driving at traffic lights but once u keep drivivng it cools down quick..

[egSi]

**** good luck with this one richo, seems like u have all the bases covered.

sell that crap koyo and get one off me :p lol

u got pm too :)

[MR-VTEC]

alloy radiator tends to heat up quick for street driving..but for track it will cool down quicker as airflow throw constant i had a koyo radiator in my previous car and i had the problem with it heating up quick on street driving at traffic lights but once u keep drivivng it cools down quick..

this is partly why my fan is constantly on but i think our problems are a little different;)

[MR-VTEC]

**** good luck with this one richo, seems like u have all the bases covered.

sell that crap koyo and get one off me :p lol

u got pm too :)

haha :D

pm replied:thumbsup:

[iamhappy46]

Have you got a factory front bar?? Maybe the cars aerodynamics have been altered and disrupting airflow thru the bumper/radiator core

[jdmTYPE R]

did u bleed the radiator properly?? when it over heat r both radiator hoses r hot??? coz if only 1 your thermo stat might be screwed try taking the thermo stat off and see if it still over heat

[MR-VTEC]

Have you got a factory front bar?? Maybe the cars aerodynamics have been altered and disrupting airflow thru the bumper/radiator core

i have an aftermarket front bar, the main thing that is hindering airflow is the intercooler. the new front bar actually flows alot more air through the front of the engine bay:thumbsup:


did u bleed the radiator properly?? when it over heat r both radiator hoses r hot??? coz if only 1 your thermo stat might be screwed try taking the thermo stat off and see if it still over heat

yes the radiator has been bled properly and yes the thermostat is ok, please read previous posts before posting the same stuff;)

[iamhappy46]

Better to have a slighty smaller intercooler than an overheating engine... but if you must keep this setup I suggest:

Fit some foam between the intercooler and radiator cores, so that air flowing thru the intercooler is forced thru the radiator as well OR use some alloy or plastic and attach to the radiator so that it forms a 'shroud' that joins to back of intercooler and directs ALL of the air coming out of the intercooler thru the radiator.

Hope that makes sense, otherwise I might be able to post links to pics of what I mean.

[MR-VTEC]

i understand what you mean, i have thought of doing this already although i dont see it making all that much difference.

its not essentially overheating, like boiling or anything like that, i mean if i was going by the factory temp gauge like most people do i wouldnt even have noticed the change in temp so its just that it is running hotter than it really should be.

[iamhappy46]

I think this will make your cooling system much more effective with a larger amount of airflow thru the radiator. Even setting up a chilled(ice or dry ice) water spray onto intercooler/radiator would increase cooling efficiency.

Of course, as you say it is 10degrees... lot of effort but it is probably raising under bonnet temperature causing other side effects.

[barefootbonzai]

just out of interest, where is the temp sensor of your digital reader located?

[MR-VTEC]

on the thermostat housing