How come my car overheats only when im driving about 80-90mph. I have a b16 tranny so rpm is about 4600-4800. What's wierd is when i had my single slam in there, it would overheat at that speed also. Could it be the radiator? Also I just replaced thermostat and yes theres no bubbles in there.

 

Are you losing any coolant? Any coolant in your oil or vice versa? Any white smoke coming out of your exhaust? I used to run the single core radiator in my B18BT and it was fine, so the stock radiator should be fine for you. You could upgrade to a dual core rad or an aftermarket aluminum unit, however, I think you may have some underlying issue with your setup.

 

If you can locate a laser temp gun, shoot the radiator and see what the temperature drop across the radiator is. If it is plugged then the temperature will drop dramaticaly.

 

nope not loosing any coolant and I do have a laser temp gun i will try that out.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by stock_honda_coupe &raquo;</TD></TR><TR><TD CLASS="quote">If you can locate a laser temp gun, shoot the radiator and see what the temperature drop across the radiator is. If it is plugged then the temperature will drop dramaticaly.</TD></TR></TABLE> nope temperature doesnt drop. could it be that the radiator is too small? should i just upgrade it? daym this is wierd. also one thing i noticed is when it is overheating and just coast going downhill but still in gear, it will cool down.

 

Are the fins for the rad clean and not to damaged? does your coolant look fresh and clean? When was the last time you flushed your coolant? If theres to much water it will overheat easier because the boiling point will be lower.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by stock_honda_coupe &raquo;</TD></TR><TR><TD CLASS="quote">Are the fins for the rad clean and not to damaged? does your coolant look fresh and clean? When was the last time you flushed your coolant? If theres to much water it will overheat easier because the boiling point will be lower. </TD></TR></TABLE> yea the fins are clean and fins are still straight. Coolant was changed when i noticed it would overheat. So now it has fresh coolant and still overheats. But why only at 80-90mph? It has just enough coolant, radiator is topped off.

 

make sure when your car is at full operating temp that the fan is turing on.

 

The fan would not be the problem becaus it turns off at highway speeds because it can't turn fast enough and just restricts air flow.

 

I've never heard of the fan "turning off at highways speeds" before.

You could check the temp-sender, it may be giving your fan a mixed message and not telling it to turn on when it should. I had this problem on my 1G CRX.

In short if the fan turns on when the motor is in the operating range of the sensor (ie: hot) then the fan should always be on when in this range regardless! And the point of having a fan is to draw air accross the exposed fins faster allowing a temperature drop to cool the circulating coolant. The fan does not restrict airflow when it's job is to increase air flow.

 

yes the fan is turning on. I already changed the thermostat and the coolant. This is how i did the bleeding. Turn car on, heater on full blast, radiator cap off, put coolant when needed, wait for fan to turn on two times then top it off and put cap back on. I made sure both bottom and top hoses were hot. I will try a different cluster next. Also take note that all i needed to do to bring the temp back to normal was coast in 5th gear going downhill and it will go back.

 

come to think about it, do you think the head could be liftingbecause when i am coasting in 5th gear downhill isn't that causing vacumm in the cylinders causing it to suck the head back down making it seal and go back to normal?

 

try to keep this up top!

 

?

 

have you ever changed the water pump? try power flushing the radiator maybe there's some rust inside slowing it down. some guy with an accord have the same probably and he just need to flush out the rust. try a spare radiator if you have one i guess...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hondmywrld &raquo;</TD></TR><TR><TD CLASS="quote">have you ever changed the water pump? try power flushing the radiator maybe there's some rust inside slowing it down. some guy with an accord have the same probably and he just need to flush out the rust. try a spare radiator if you have one i guess...</TD></TR></TABLE> daym i might just have to do. so you guys dont think the head is lifting?

 

The head would not be lifting.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by stock_honda_coupe &raquo;</TD></TR><TR><TD CLASS="quote">The head would not be lifting.</TD></TR></TABLE> why not?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 93ej1 &raquo;</TD></TR><TR><TD CLASS="quote">make sure your car has ll fluids</TD></TR></TABLE> what are II fluids?

 

ttt

 

There like 40lbs of torque on those head bolts, I don't think it would lift.