ATXKJ wrote:
Problem 2) The radiator overflow tank is dark.. - I pop the lid...Oil .. I check the engine dipstick - slightly low no foam. - okay I've seen this a couple of times on gas engines - a blown head gasket or a cracked block I'm not happy (I later checked the service manual - I do have a 3rd option - the CRD has an Oil cooler that runs engine coolant -if that blew a gasket or cracked it's a simple fix - the cleanup won't be simple - it's messy).
Are you getting any abnormal pressurization in the surge tank? Keep in mind that the contents are already under pressure but excess pressure should relieve itself through the overflow tube. Detroit Diesel uses the same style heat exchanger on buses (but much larger) and I have seen a few leak. It's usually a gasket and normally from a sloppy install. Normally you will see very fine antifreeze droplets mixed into the oil on the dipstick (you have to look very carefully to see them) when this happens. If they don't want to service this problem until it looks more noticable, I would pull an oil sample for analysis to be on the safe side. One other thing to check is casting sand in he tank which is also dark. Some here have needed this to be flushed.