CAT C-15 Acert .... multiple problems??? HELP

Hi, I have a 2005 Columbia carhauler with a CAT C15acert. This is my first CAT, just bought this truck in June 2012. Since: First week I had it it blew a radiator hose, had that replaced. 3 months later Cracked #6 liner was pushing pressure into coolant sytem..resulting in a Gold kit install at Cleveland Bros in PA. Ran ok after that, for 10K miles. Then while driving last week on a cool day water temp spiked to 250, I shut it off and got towed to a CAT dealer, diagnosed with a sheared off impeller on water pump..result, replaced water pump..ran ok for 600 miles, while loaded climbing a grade I noticed a vibration, my first thought was the driveshft u joint bolts werent tightened after the tow. Pulled off, looked around, then noticed the engine was still shaking/vibrating in idle. Went to TAG truck repair in Jackson, TN found a broken (clean off)#2 injector rocker, fortunately it didnt damage the cam or the injector...had that repaired went on to Memphis, back to Nashville, up to Clarksville then back to Smyrna to reload and stayed the night in cookeville, tn (approx 44o miles later) I could smell coolant when I got out to stretch, so I took a look....coolant stains on top of the engine.. I assumed it was left after the injector rocker repair and didnt get cleaned. ( I told you this is my first CAT ). I kept an eye on coolant level and the coolant stains on the engine...the stain/wet areas got larger and larger, like I drove through a cooalnt rainstorm, but its not using alot of coolant.. i kept topping it off to be safe until I could get the load off and get back to my homebase. I made it, gauge never showed it get hot, or cold, stayed right around 190. I hear a "slapping or tapping" sound at irregular intervals, sounds to me like a thermostat, but I am no diesel (cat) expert. I can also hear from inside the cab a drony hum as if the water is pushing through the surge tank cap, but when I check the water and top off there is very little pressure in the tank, as i loosen the cap there is a slight hiss then i can top off. I called my shop on my way home and explained all this...They said that it is possible to cut a 1/4" hose when doing the #2 injector and it can make this kind of a mess. I cant find a 1/4" hose anywhere around the top of the engine..Still looking, going to do a cooling system pressure check later today.
My question is with all these coolant system related issues am I missing something larger? Cleveland Bros inspected the head, and stated it didnt have any cracks. The engine seems to run fine but I am losing my confidence in this thing. I ve been loaded every time there is a problem, I haul new cars and dealerships get ugly if they are a day late. I ve been a week late twice. Are these random 500K mile problems or did I buy an albatross?
Is there some type of diagnosis/checkup I should have done? I just started using a CAT dealer in my town as my regular mechanic. I need to know what to ask them to do for me. maybe a match and some gasoline? I am worn out mentally and financially with this truck already. Please give me some real advice.(hope). Thanks

 

The overflow hose runs down the back of the surgetank, nowhere near the #2 injector/cylinder head cover. It was not doing this before that repair so I dont feel it is an overfilling issue. Thanks

 

Im sorry I didnt post the answer to the mystery sooner, truck has been wearing me out with nickel and dimers. This problem was the radiator. 700 bucks.