Motor - d16a6/z6 mini me
Mods - 3" s-ram intake w k&n, skunk2 intake manifold w ls tb, ebay header, test pipe, 2.5" mandrel bent exhaust, oem crx hf oil cooler added, obd1 converted using a chipped ecu on chrome gold with a custom z6 basemap. not throwing any codes

Cooling System Specs:
OEM Honda water pump and thermostat, aftermarket stock replacement single core full size radiator, stock spec radiator cap, new coolant temp sensor, fan switch and coolant gauge sensor, pretty much every hose is brand new, no known leaks.

Problem:
I don't believe my car every fully warms up. Tonight, for example, i let my car idle for 15 minutes while i scraped ice off my car, then drove for thirty minutes then parked and let it idle for a little longer. I popped my hood, and my upper radiator hose was almost too hot to touch, i can leave my hand on it for about twenty seconds before it starts to hurt, lower radiator hose was cold. the Radiator was warm to the touch but not hot, afaik i don't spew coolant or burn it, my heater gets fairly warm but not blasting heat like my van or my buddies eclipse. when parked and turned off it cools off really quick.

the last time my fan turned on was when a coolant line popped off and i spewed half my coolant on the ground. other than that it never comes on, even after smashing and vtec cracking hard. i've replaced my thermostat twice now, i find it hard to believe that i bought two bad thermostats from my stealership

granted it's cold out right now, but shouldn't my car still fully warm up to where the fan comes on if everything is working properly? i'm going to flush my cooling system and replace with pre mixed 50/50 tomorrow.

Please if any one can give me input i'd much appreciate it!

Thanks in advance,

DCRB (Ryan)

 

put some cardboard in front of the radiator to cover it, say about 80% or fully, and go for a test drive. Usually the air stream is enough to cool the coolant completely during the winter time, especially if you are not pushing the car a lot, have huge radiator (like the EF had) or have too open bumper which lets excessive amounts of air in.

If the cardboard trick works, then it is just too effective radiator for your engine. This is common problem that can be easily fixed

 

Oh... you have a oil cooler too? Cover that! You do NOT wanna cool your oil during winter time unless you are doing some real racing AND have problems with oil temps! Even the basic oils can take over 120 °C temperatures without braking down, so there really isn't any needs to cool it down before that.

One way to get around this is to get a thermostat in your cooler lines.

 

Spend $20 on a gauge to see if its ACTUALLY not getting hot, or if your thermostat just isnt opening

 

still sounds like your t-stat.....

- maybe you put it in upside down?

- did you burp your cooling system?

 

If the thermostat isn't opening, the engine will over heat.

If it wouldn't close, then it's cycling the coolant all the time thus transferring all the heat to the radiator.

EDIT: I had missed totally your description of the hoses... Check the thermostat if you haven't checked it already.

Remember, though, the thermostat usually opens in 65 - 85 °C and that can feel bloody hot for your skin (FYI for Fahrenheit guys, human temp is 37 °C in SI system ) . Usually the thermostat leaks through even though it is closed, thus you would get a lot of heat to the upper hose after some driving, but not enough to make your radiator heat up completely.

Oh btw, are you using cabin heater at the same time? That cools down the small engines quite quickly too. --> Cardboard helps

 

i will try the cardboard trick today. yes, i am running my heater constantly because my tail lights leak and thus my windows fog up if i don't. the oil cooler is a stock one (not a plate and fin cooler) and bolts to the back of the block, it's the same as an oil filter sandwich plate. i installed the cooler as sort of a precaution on the safe side because i don't smash all the time but i do do canyon and mount pass runs with my buddies and we go ***** out... plus they're all boosted or 200+ hp and i'm tryin to keep up w my cute ~135 hp lol yes single slam vtec cracks hard

the thermostat is installed correctly with the bleeder nipple on the top, system has been burped. i will invest in a legit temperature gauge so i can have piece of mind as well. if my thermostat is infact i'm going to be irritated, this is the second one i purchased from honda, the old one did the same thing. i'm not using knock off auto parts parts i'm using oem honda parts

 

Ryan, I'm not too much of an expert on the subject, but to me it sounds like what my 1st crx did. My normal operateing temp is always below half and never had any trouble. (that's in florida heat and in kentucky cold) The thing that gets me is your top hose came off and you lost fluids threw from there engine getting too hot and turning your fan on, all normal (for a problem with the cooling system.) Mine probbly blew on mine because i was useing better hose clamps. (I replaced the stock ones with the ones you can torque down.) Your water pump may be going out. Test your water pump start the car squeeze the top hose if you don't feel flow you're looking at a water pump. hope that helps, it's alot better than putting a piece of cardboard up, (sounds ghetto to me, but could be a cold weather thing*). (don't do this when it's hot like you said the water could get the pressure from the heat,(could be the reason you lost the hose that time) and of course you may burn yourself.) But as far as the fan it comes on and off depending on the core temp. I hope this helps, i'll continue to research for you. ----Kevin

 

Also your vtec should not engage if your engine is not warmed up. It will not engage unless it reaches 68 C, or 168 F. hope that helps.

Temp could vary, thats just information I pulled off my hondata s300 program.

 

what does "vtech" have to do with Honda? lol

 

hmmm Kevin thanks for the input, it was actually the metal t bar off of the intake manifold that popped off when i installed my skunk2 manifold. vtec does engage i can hear it and feel it. i will test the pressure when i get my car home, it's sitting out in gresham with a dead alternator and battery not sure how it happened... water pump shouldn't be bad, it is a brand new honda water pump with maybe 6k miles on it....

 

If your top hose didn't get poped off by coolant temp your most likely going to have a good waterpump. I'll keep searching for an answer.

Thanks Deets, bad habbits die hard. mispelled that one =P, Vtec*.

BTW Deets nice 89 CRX.

 

I found a forum with someone having a simular problem, here is the link. They came up with a fix.

http://bbs.zuwharrie.com/content?P=c...topic=88279.15

 

ya no the top hose stays on it was the brass bar that's pressed into the manifold that popped off when i stomped on it to give my car a good ol butt dyno... so obviously coolant is flowing quite well. just think all this is odd...

 

first off - do not use cardbaord to block the flow of air on the radiator. there is a reason air is spose to flow across the core- to cool it. its not even reasonable to think that 30 degree temps can completely cool the extreme high temps caused from a combustion engine. secondly- if u are using a "modern" oil viscosity (aka 5w-30) versus straight 30 weigth- u should not even have to think about heating engine oil in the winter months. you first have to tackle why the engine is not at operating temp. like was said before check the guage and also the ect sensor and also the guage sensor. an easy way to check the guage and guage sensor is to boil a cup of water in the microwave, then place the unistalled guage (with the pigtail hooked up) in the boiling water and see what the guage does. remember that cooalnt never boils if the cooling system is operating and holding preasure as it should. so the temp guage in the boiling water should read pretty high. to test the ect sensors (one on backside of block, one under the disrtibutor) u could find the spesifications (maybey mitchell manual or internet). ect will read in olmes. test cold ect with multi meter, refer to specs. same concept- boil some water, with multimeter hooked to ect, drop in water. then refer to specs. or a much easier way, but more expensive- buy an old school scan tool. i prefer the second. it is also possible (like said before) u have a stuck OPEN t-stat. remove t-stat. same concept again- boil some water. drop t-stat in water. then watch it open. remove from water, then watch it close. usually weak water flow (restriction such as clogged radiator or defective water pump fins) will lead to an overheating issue as u are driving the car. so most not likely the culpret, but as i have learned over the many years of tech work- anything is possible. an easy way to check. find a hose that can be reached past the highest point in the cooling system. start car, remove that hose, plug the nipple from where u pulled it off, hold hose higher than the highest point, raise rpms. see if coolant flows out. if it does, u got good flow. then see if u cant rig something up to check radiator flow. make sure radiator cap mis holding pressure. the last thing that i will suggest and prob should be at the top of this list is to make sure ther are no air pockets in the cooling system. i found hondas extremely hard at times to bleed. do not relie on just a bleeder valve. use a cooling system pressure tester to force air out of a small hose near the highest point. or with a funnel fitted onto the radiator, fill w water, run the car till warm, sqeez all the hoses. u will see bubbles raise out of the funnel, then it will pull water in its place. it may be nessacery that an air operated vacuum be hooked up to the radiator and suck out all the air and coolant, then let the vacuumed system pull in coolant from a fresh jug. a little expensive to buy the tool, but i have seen it almost impossible to properly bleed a colling system on certain vehicles including hondas. remember- a liquid cannot be compressed, but air can be. if a hose has blown off, possible that an air pocket caused it.