A collapsing lower hose is pretty obvious if you have someone rev the engine while you watch the hose. Have them rev it up a few times, then have them bring it up to highway rpm, like 2500 rpm, and hold it there for a few seconds... If the hose is the problem, it will collapse somewhere along it's length with the rpms up.
Ok! I see where ur coming from 230-240 is to hot. I do agree that may well be where the problem lies. To say the least, that is the least expensive next thing to try. I recall putting on a new lower hose and was suprised it did'nt have a spring . I hp that solves the problem
you might want to verify the accuracy of the gauge in addition to all the other good suggestions. When it overheats, does it boil over or gurgle when you shut the engine off? An infared thermometer measured on the metal part of the intake right behind the thermostat housing will confirm your temp. (don't get this device close to the distributor, it fries the electronics! ask me how I know) Is your coolant mixture greater than 50/50 water/coolant? Is your water pump stock and spinning the correct direction for the belt system?
I just slightly unwind the coil on the water pump end to just bigger than the water pump inlet. that way when it's installed, the spring rests against the water pump metal housing and shouldn't get sucked in.
my mixture is about 60 water and 40 coolant or a little more water. and yes the water usually gurgles out and also some steam comes out of the overflow hose connected to the radiator.
I had the same problem with my lower hose, it would close when driving... I put a metal flex hose(mistergasket) on and no more problems...
Might be worth getting a block tester from NAPA. If you haven't used one before, it uses a chemical that can detect the presence of combustion gases in the coolant. That might eliminate or verify a head gasket problem. Not too expensive and only takes a few minutes once it is warm. Use the air bleeding method mentioned in one of the previous posts and make sure the thermostat is open when you test it and don't suck any coolant into the tool. It won't be accurate if you do.
I ended up buying a flex hose and then cutting it open and putting the coil spring that it had inside of it into the molded hose i had on my car. It was kindve hard getting it inside the molded hose but now its seems like everything is working fine. thanks for the help everybody.
the way i "burped" my systems was to have the car sitting there off, cap off and pump the upper radiator hose allot until the coolant level stops dropping.
this, then i test it by running with cap off to ensure i got every little bubble 95% of the time it works just squeezing the upper hose a bunch of times to force coolant into the block and forcing the air out.
You can't just squeeze the hose to get air from the engine. The point of running the car to operating temp is to open the thermostat and to use the water pump to circulate the water, especially to get the air from the heater core. To pump the top hose cannot do anything if the stat is closed. The stat only opens for a short time each cycle, and that is why you must let it cycle several times.
Oh, and RUBEN, glad you got it solved! With the custom radiator and fan, it sounds like you should have a top notch cooling system.
I have found an easy way to bleed air when refilling your system. Leave the heater hose off that goes to the intake manifold on a V8 or to the head on a 6cyl. Fill the radiator slowly and when fluid appears,just put the hose on. This lets the engine fill with coolant and you'll have to add a tad more to top up the radiator!
