Cat 3116 Oil Cooler Repair

This Cat 3116 oil cooler was leaking oil so disassembly was required. On a Thomas Saf-t-liner school bus the complete air cleaner and piping can be removed to gain better access to the cooler and turbocharger. The turbo must be removed to get at all the fasteners on the cooler assy. Before removing the cooler parts the coolant must be drained from the block or radiator. There is a block drain (hex head) at the right rear of the engine behind the turbo.
Above you can see the oil cooler parts. The outer housing and the cooler itself are seperated by 2 gaskets which have hardened over time and became brittle.
Using guide bolts slide the first gasket and then the cooler bundle over the guide bolts. There are also to o-ring seals located at the bottom of the cooler.
Once the outer housing is installed the m8 bolts are installed and torqued to 20 ft. lbs. This isn't a major job but it still takes time and patience to get to the cooler. We have 13 Cat 3116 engines and the oil coolers have never failed as far as leaking oil into the cooling system.