It will NOT cool down.

[Camel Filters]

I have tried everything and every suggestion.It wont stop over heating.

Specs: 93 hatch with jdm d15b vtec motor.

I went through 3 thermo stats. One napa, one checker, and honda oem. NONE worked. The one that came with the swap worked for about a year with the temp rising a bit only to fall if i got on it a LITTLE bit. Not hard at all just down shifted and let it ride in gear it would drop and be good for a while.
New radiator and cap. Those appear to be in fine shape. No leaks any where. Absolutely NO AIR in the system. I have bled it thouroghly to where there are zero bubbles coming out. I did a head gasket cause all was fine until it started to push bubbles and coolant back into the reservoir (overflow) when i would turn the car off. I researched that this was exhaust gas escaping into the coolant system from a faulty gasket. Replaced the gasket with honda oem and seemed ok for a day. Also flush filled radiator and oil change new spark plugs for good measure. Today she heated up non stop. If i down shift to third and keep it going it will drop a bit and hold but i can only go like 30mph and thats obviously not the solution. I am out of answers and cant figure this bitch out. The fan doesnt come on properly and i have gone through two thermo switches and its not the relay. If i hot wire the fan it does work but runs too cold. I have not tried that since the recent overheating but i dont see why it would help cause it occurs when i am moving in the 20 degree weather which would simulate the fan on its best day........ HELP ME!!!!!!!!!!!!!!!!!!!!!!

[Camel Filters]

bump for warped head possiblY????

[J.Dub]

wire up the fan directly to the battery with a off and on switch and turn it on everytime you drive and turn it off everytime you get out

[J.Dub]

mine did the same thing until i did that to the fan

[boostedEG]

wire up the fan directly to the battery with a off and on switch and turn it on every time you drive and turn it off every time you get out

you cant wire it directly to the battery.... you must use a relay which is already built into the wiring, all he needs to do for that is to jump the wires on the fan thermo switch, which he already tried. and although that may keep it from overheating, it isn't fixing anything.

Camel Filters,
do you have an aftermarket radiator? i installed one of those ebay aluminum radiators in my car and on hot days it would always get hot.

have you ever used "stop leak" in your system? I've heard its quite common for that stuff to clog a heater core, so I'm sure it could theoretically clog a radiator up too.

[boostedEG]

oh and are you sure its actually overheating? and not just a faulty gauge?

[Camel Filters]

yea i have a performance radiator from their shop at I25 and broadway. Never had problems there before and it has been key for months. Never used stop leak or anything. and my heater core is bypassed due to it leaking inside the car. yea i know...no heat this winter lol. and yea i did try the fan... the only thing i can think of is the thermostat isnt opening...but i tried 3 including honda oem. I am going to try running it tomorrow with no thermostat cause if i need to i only have to drive about 8 miles. so if it stays ok then i need a very cold opening thermostat i guess. I do know that the d15b has an unusually low 170 degree thermostat.... perhaps the usual 180 degree ones arent opening soon enough...yet i would think when it hits the extra 10 degrees it would open up....

[Camel Filters]

and for it to boil over into the reserve i would think the gauge would not need to be faulty...would it?? It could be the gauge but it is getting hot!!

[vince]

I had the same prob, i changed out the head gasket and milled the head and its been running perfectly ever since.

[Camel Filters]

its so frustrating... I need the ol hatch for delivery. Its how i make my $. I am almost ready to just sell it and start over with a teg or newer civ. I have everyone i know scratching there heads. OH ... and it does the hunting idle thing too. Dont know if that helps but its the signature honda vroom vroom...

[boostedEG]

hunting idle could be a number of things...

1) bad IAC
2) bad thermo something something something valve (i forgot the name) but only some T-bodies have this valve anyways.
3) air pocket in cooling system, as the iacv works off of coolant temp.

i know you said you bled the system numerous times, but try doing it again, and jack the front of the vehicle up as high as possible in the air. you want to make sure the radiator cap is by far the highest spot in the system.

[Civic-8442-]

i have a sohc vtec head man ill deliver tomorrow asap for 60 bucks LMK ASAP.

[Camel Filters]

yea i did just do the head gasket yesterday... perhaps milling the head will be the final option but i may just buy 8442's and slap it on. then mill the d15 head and sell it or something...so confusing

[Camel Filters]

yea the FITV fast idle thermo valve. I have tried adjusting it but same result. I will try re-bleeding it too. I am going to put her in the garage for some down time again tomorrow...Just sucks cause i am in an apartment and have to work around my buddies schedule to hit up their garage...

[Civic-8442-]

well LMK man oh and he he forgot too mention its missing the valve cover studs,vtec solenoid,dizzy,IM

But you can switch everything over from your other head.

[Camel Filters]

but again i will let you know 8442!! good looking out. I will try running no thermostat tomorrow to see if she stays cool. If thats the case then looks like the boys at honda need to get that part for me. I think it takes a bit cause i need the one for a d15z1 or the actual jdm piece from japan cause they open at a MUCH cooler temp i believe...

[Camel Filters]

true i do have all those pieces if i need to swap em over!! Thanks again EVERYBODY!! If this site had an ass....I think i would have a brown nose lol

[boostedEG]

FITV, thats the one i was talking about. it will cause the idle to surge, but wont cause any overheating problems.

i've never had to mess with one myself, but im told there is a plunger inside that gets loose, causing the idle surge. if you screw it back in the idle will smooth right back out. if you have already checked/corrected this, and the idle still surges then the FITV is not your problem. that leaves a bad IACV or an air pocket. im leaning towards an air pocket, as that would explain your overheating.

[Camel Filters]

yea i did screw it down in the fitv. I had that issue on my old b16 hatch and it fixed the idle. But yea... i will be searching for air again. I am praying somehow its the thermostat...though i am unsure. I will definetely keep this post going if the outcome is good or bad. Thanks again all. My car is ;OwnEd;

[Civic-8442-]

i also have a thermostat for a d15z1 LMK lol....

[B20badboy]

Did you replace your sensor?

[eg_project]

I had the same prob, i changed out the head gasket and milled the head and its been running perfectly ever since.

ditto. mill the head, its like 30 bucks. it may look straight with an edge and whatnot, but it may not be, just mill it and do it right. I have a boosted b7 too.

[Punting_midgets]

mad it was the thermo i guess. the bottom hose never liked to heat up. But i could get it to cool down by downshifting and let it ride in gear.I figure the t stat would open from pressure. My guess is that it finally decided to stick shut and not open anymore. Now while running no t stat it flows perfectly and bottom hose warms obviously. It must have been stuck on the top side never circulating. Also as it doesnt reach optimal operating temp..(just below the normal spot) the hunting idle does not occur either. All things appear good at this time!! Thanks for the input ya'll and i will be ordering a mugen or spoon thermo that opens colder since that motor likes a 170 degree stat anyway. Or i will let you know 8442!! Thanks again gentlemen:drink: :drink:

[Camel Filters]

But thanks again all!! She seems to be cool as ice now lol.(Literally) I will be keeping driving to a minimum till i get a new car,swap, or tstat. Not sure which yet but thanks for the support gangstas!!!!!

[CERO F1]

If your still in need, you can put an emissions tester in your coolant resivoire, it will read hydro carbons if your head isnt sealed completely

[marcrx5]

If your still in need, you can put an emissions tester in your coolant resivoire, it will read hydro carbons if your head isnt sealed completely

I'd give this a shot, it sounds like you're just masking a problem buy not running a t'stat.

[Camel Filters]

yeA... the problem is a bad t stat. I dont like masks.... do you sir???

[marcrx5]

yeA... the problem is a bad t stat. I dont like masks.... do you sir???

I just think it's odd that you've tried 3 different t'stats, with the cold weather we've been having lately, and it still overheats. Obviously running no t'stat isn't going to overheat, but I don't thing a 180* vs 170* is going to solve anything. My guess would be either inproper installation (either not bleeding the system properly, or installing it backwards, which, iirc, you can't do on a honda) or the head needs to be milled. If you had to do a headgasket recently, there's a very good chance that the head is no longer true.