I have a 93' dodge dakota 3.9 and have replaced thewater pump, thermostat 195 degree, upper and lower radiator hoses, and bypass hose, and I am not getting any heat or water movement. I have driven it for an hour and can take the radiator cap off and there is no pressure build up, so I bought a new cap 16lbs. thinking that was the problem, still nothing. I am not loosing any antifreeze, no leaks at all. I squeezed the upper radiator hose that is hot but cannot feel any water running through it, nor the bottom hose, but my temperature gauge stays about a quarter inch above the cool mark. I have also ran preston flush and fill through the cooling system. But no luck. I don't think it is a head gasket problem because there is no water in the oil or oil in the water and no water or white smoke coming out of the tailpipe. I did notice when squeezing the upper radiator hose you hear a gurgling sound in the engine block. Any help on this would be greatly appreciated, the only thing I haven't tried is to back flush it, would that be of any help? Thanks, the dakota.................p.s. other than that the truck runs great at 175,000 miles.

 

sounds like you have an air pocket in your engine.

try running it without the rad cap on and see if that will do anything. if not, then try flushing evrything out and see if that helps.

did it do this before you replaced everything?

 

you also might try reving the motor some to get the coolant flowing... that may help get rid of any air pockets trapped inthere.

 

ok i have flushed the heater core and then the whole system and im not getting any flow or no pressure build up. i have let it run for 2 hours and thats without the cap on. The heat is warm i can put the radiator cap on and drive around for 1 hour and take the cap off with no air pressure at all???? no fluid comes out either but it is staying full. I even took the t-stst out and the same thing and also parked it on a hill like a guy told me but nothings working.... If i had a cracked head wouldnt i be loosing fluid? cant figure it out the dakota...... thanks for your help.......

 

ok first you have to be getting water movement or your engine would be an anchor by now.That being said how do you mean no heat? none from the heater or the gague is showing cold? if you're getting no heat from your heater I would say you're new thermostat is bad, ie stuck open(it happens) if you're simply not showing any warm up on the gague then the gague or circuit is faulty..I'm leaning toward the thermostat, reason being you said you removed it and there was no change if the thermostat is malfunctioning then the water won't move through the system slowly enough to get sufficiently warm for heating the interior. one other thing try putting a piece of cardboard in front of the radiator, you may just be pulling too much cold air through it and cooling too well. My peterbilt does that in extreme cold...lemme know

 

thanks boomer_87 i put the cardboard in front of my radiator and that was it atleast for driving down the road but sitting still the fan still keeps it to cold and keeps the t-stat from opening, it will not open sitting still motor wont get hot enough. i took the fan off and the temp climed an d the t-stat opened. so my motor is staying to cool should i put a lower t-stat in it so it will open or will it be fine the way it is ? thanks for your help once again

 

a cooler T-stat?I'm really not sure,since you're having an over cooling problem you don't necessarily want a cooler stat although it may opensooner I'll have to check.One quick question,what is you're antifreeze mixure?Because I know from experience that a pure antifreeze system can cause an over cooling problem in which case you may simply need to add water to you're system so it can get hot.Remember what it says on the bottle antifreeze/antiboil...