Upper hose is collapsing!

phish1270 said
The motor supposedly has only had about 700 miles put on it since 2002 so it very well could be full of crud. "One man's project not done right is another man's nightmare & a mistake is his wife's eyes". I am going to pull the thermostat & leave it out, it sounds like I really do not need it especially living in the south. Then I am going to drain the rad, disconnect all the hoses & do whatever I can to flush out the motor. I will do some research on the rad cap pressure but I have seen guys on here running caps as low as 7 lbs. I just have never seen an upper hose sucked in before, something is creating a bunch of vacuum when the motor is shut off & cooling down. I just thought I would see if anyone else had ever had this issue because like most things there could be various causes & I hate just guessing. The flush should not be very costly so it is a good starting point. Thanks guys. Let me know if anyone has anymore ideas & I will post results as I try things. It is just about time to give up on this motor & start building one of my own.

It sounds like your cap is the issue. When the engine cools it is trying to draw coolant from overflow bottle (If you have one) If you do not have one then would still be cap. As the engine cools and contracts it will create a suction and draw fluid. If not and cap is not venting for overflow, it will not draw and the extra "vacume" will show as colapsed hose in the morning. It is got to be with the cap or cap gasket. Make sure if you are using overflow bottle you have a cap designed for overflow system. Alot of times with the new overflow kit they sell has a 2nd gasket to use if your cap was not intended for return system. I would still flush and check the thermostat in a pot of boiling water on stove before reassembly. If your not using over flow, same thery on drain hose. You can also take off drain/overflow hose off at cap and blow air through it to de crap, and don't use your lips unless it's cooled!!
Good Luck & keep us posted!