cooling issues

[jesus_ralliart]

I'm running a koyo small radiator and the car is overheating or so the guage says. Previously the fan stopped spinning so we ran a wire so the fan could be switched on via a switch. So, now the fan spins but the car still overheats. Also, a previous owner set up the coolant overflow to a can which didnt work. It didnt work in the sense that it probably wasnt built to hold hot coolant and pressure, so we sealed off that can's coolant line. So, does anyone know why the car will still overheat? Basically, the radiator has coolant running through it and the fan now works. Is the radiator too small? I thought I read things about guys on here running the koyo. The previous owner said he had no problems with it.

So, whats the coolant temp. at operating temp?
Car is obd1 right?

 

[prove_it]

car is obd1 yes.
I'm assuming your coolant level is good.
You may want to check to see if the thermostat is opening. Check your cooling hoses they should both be about the same temp after it warms up, If not then your thermostat is sticking closed.

Otherwise you may have an air pocket in the cooling system.

 

[iLLeffeKt vr-4]

How thick is the radiator? How big is the fan and how much CFM does it pull? Is it a pusher or puller?

 

[mitsuturbo]

I'm running a 2 core "honda civic racing radiator". Yes, the kind you see on ebay all the time. 1/2 width. I got a straight blade high flowing 14" fan and put on it, and was having mucho problemo with it running really hot..... until i threw in a 160deg thermostat. Now the car takes forever to reach operating temp and if i dont let it warm up before driving, if it's really cold like it was back in December, here in Seattle.. it may not really warm up completely at all. I was in Utah at the tail end of summer when i put it in, and it was some 90 degrees, so that attributed to the overheating. Now that i've come back to WA i dont think it will ever be a problem, and i may need to put a warmer thermostat in. The car now runs warm enough for the heater to work..but barely (like i said, when its cold out). I think the smaller radiators are just a lot more susceptible to environmental (ambient air temp) changes.

 

[prove_it]

I plan on running the same radiator too someday. I think what you may want to try is a 180 degree thermo and use water wetter. In our drag evo/dyno queen we used straight water with a bottle of water wetter and we could do back to back 1000 horse dyno pulls no problem with overheating. We used a civic sized half radiator too, it was built for an evo but the temp never crossed the 210 barrier. Worth a try and it's pretty inexpensive.

another question is how easy can air get to your radiator?

 

[jesus_ralliart]

so you guys think its the thermostat huh. yea, i haven't had time to even look at the car(school comes first) but i guess i'll end up investing in a new thermostat.

radiator recieves plenty of air, fan now works, and coolant level was done when we first tried to figure out what the hell was going on.

So, i guess ill top off coolant/ water wetter(whats left of the bottle.. bout 3/4) and see what happens. If problems continue(which i assume they will) ill be in the market for a new thermostat.

And, if that doesnt help.... Who knows.

 

How old is the radiator cap? That is one thing you should always check first when dealing with a cooling problem. If the seal on the cap is old and therefore not sealing properly/holding pressure then you're going to overheat even if everything else is perfect.

Easy and cheap way to start would be to get a new radiator cap, and a new thermostat. Replace the thermostat now while the coolant level is low and you won't have to drain any off to do it later.

 

bump for thermostat

 

[Terrance362]

x2 thermostat

 

[jesus_ralliart]

Got the new thermostat, made sure to pump all excess air out the system, filled coolant up and fan works. Car officially doesnt overheat and aside from some cosmetic issues, is ready for the road.

 

[bazeng]

Bringing this back from the dead,
I'm going to try water wetter on the vr4.

Now what is the negative of running water wetter (1bottle) and the rest water?
We don't get freezing temps here, so is it going to hurt our cars?

I believe it is not good for magnesium and antifreeze(which is not an issue for us).

Will it be safe to do on the VR4?(long term).

Thanks

 

[kama1]

been using it for the past 5000kms with no issues
1 bottle and the rest water