overheating and fan on constant, help
 

ok, i have a 90 civic hatch 1.5

The radiator fan is on constant, never turns off when engines on. Im also overheating after some driving. I have new hoses/radiator cap/thermostat going in tomorrow, radiator is new. Any suggestions on what is causing the fan to stay on constant? anything else i should look for to stop the overheating? thanks

Re:overheating and fan on constant, help
 

i bet the fan is one cause your thermostat is fried ...just a guess

Re:overheating and fan on constant, help
 

yeah, i'll see tomorrow for sure. ;D

Re:overheating and fan on constant, help
 

what about the water pump? my fiero use to overheat real bad comes out my water pump was going out had it replaced np.

Re:overheating and fan on constant, help
 

The coolant temp switch? have you replaced that yet?

You could have a slightly blown head gasket.

Re:overheating and fan on constant, help
 

I also have the same problem, just never got around to fixing it. I don't think it would be a partly blown head gasket in MY case. I've had the rex for 2.5 years and the fan is always on... until I melted it today with the exhaust from my turbo ...

Re:overheating and fan on constant, help
 

yeah if the thermostat etc. doesnt fix the overheating, ill change the waterpump. Jeff, i havent changed the temp switch, how can i check the head gasket? I have a complete gasket set, i guess i could slap on my a6 head, swap it while i change the head gasket, waterpump and timing belt...i would just swap the whole motor but have no access to a lift...opinions? thanks

Re:overheating and fan on constant, help
 

do a leak down test to check for a blown head gasket. Easy ways to check for water pump is broken is to touch the hoses going to and from the rad. If they are hot then the thermostat and pump are good cuz you have coolant flow.

Re:overheating and fan on constant, help
 

Thats not entirely true, you could have coolent flow going through the top radiator hose(meaning the t stat is working) but your water pump could still be faulty. Dont wait on this one, my water pump leaked for a while but i didnt know it until i was racing one day with a turbo rx7 and a turbo hb. I noticed i had a problem when my temperare gauge was way past hot, opened the hood, absolutely no fluid in the radiator... a week later i was driving like 65 not even under boost, and one of my rods just snaped in half. That sucked. Dontwait around to fix this problem.

Re:overheating and fan on constant, help
 

thats why I said check both hoses ;)

Re:overheating and fan on constant, help
 

Yup they are all right.
I had this problem for a half year and till last month I fixed it.
I bought a new temp switch and no it wasn't that.
I drove for like 4 month's without fixing it, cause it was winter and the temperature stay low...It was my thermostat tht was faulty, cause the heater didn't work so I waited till it got a bit warmer to replace it(I don't have a garage), but than the engine began to overheat again..I guess not replacing the thermostat damaged the waterpump maybe cause it was leaking a lot of fluid...my radiator was bone dry. I got a replacement thermostat from the spare engine in the shed replaced it and the heater work again, but I had to refill the radiator every 2 days and finally got some money to buy the waterpump and now it's all good ;D. What a nightmare new temp switch new pump good 2nd hand thermostat(on a budget)... damnn my temperature doesn't even go past 1/3 of the gauge now.
Check you heater see if it works and check if you waterpump is leaking.

Re:overheating and fan on constant, help
 

heater works, the only leakage i see is on the upper radiator hose(old), although i didnt look really well at the WP. I too dont have a garage, wanted to change everything out yesterday but it was storming all day!! maybe tomorrow. Thanks for the advice everyone, Ill let ya'll know how it goes...

Re:overheating and fan on constant, help
 

did you take out your ac?

Re:overheating and fan on constant, help
 

didnt come with a/c...

Re:overheating and fan on constant, help
 

ok, changed the thermostat, radiator cap, both hoses. Damn thing is worse now. Before i would just turn the heater on and the temp would eventually drop, now when it heats up and i turn the heater on, the temp just keeps rising. some times at idle say like at a stop light the temp is damn near redline, then when i drive it drops to 3/4 then back up to redline. Someone told me that i dont need the thermostat, i can remove it??? WTF, Im buying the water pump tomorrow, hope that solves the problem... :-\

**im also getting CHECK ENGINE light, vss and injector codes...

i have a d16y8 complete head, should i yank the D15B1 head and minime it since im taking the timing belt and water pump off anyway? Ive never heard of anyone using the D15B1 w/a minime, just the B2's a6's etc. :-\

Re:overheating and fan on constant, help
 

the most hardest cause well most expensive and hardest to fix i should say would be a head gasket.

pull off your radiator cap and see if there are spots of oil in it. thats the easiest way to check for a head gasket failure

Re:overheating and fan on constant, help
 

well i took off the timing belt covers and the belt and waterpump appear new, theres no leakage by the WP, i have a complete gasket set for the motor, free from a friend :) there is a lot of build up around the area where the head meets the block, resembles sludge. i assumed it was because the upper rad hose was leaking and dirt and time caused the build up, I guess ill just yank the head and put the new gasket, seeing how everything else didnt solve the problem. so would i be ok using the old studs for now? i just need to get the arp studs and a ecu (does the pm6 plug and play w/my STD plugs?)) then ill minime it, but for now i just wanna be able to drive w/out overfckheating!