ok, time for an update.
engine lasted for about 300 miles. then a little knocking quickly developed into a hard nocking during cruise. took off the oil pan and found that #1 rod bearing was causing knock.
although the engine ran fine, I found these blue traces of coolant on all four side of the engine.
took the intake of and guess the cola can isnt strong enough to stand exhaust heat.
took my heads of and found black debris in them
most of it collected at the cabin side (rear) of the heads
closer inspection of the engine showed that also #1 main bearing was gone
other bearings dont look better
I havent really found the answer as to why the bearings went out so fast, ut decided to buy a new crank and reuild it again....guess some dirt got into the oil system and destroyed them