Chevy C6500 Rollback Wrecker with Wheel Lift. Caterpillar 3126b 6 cylinder diesel. Replace IACPV valve. DIY and save big bucks.The IAP Control Valve is an el. (6) Connector for the IAP control valve (7) Oil cooler (8) High pressure oil passage (9) IAP sensor (10) Fuel supply passage (11) Fuel transfer pump (12) Secondary fuel filter (13) Primary fuel filter/water separator (14) Fuel tank (15) Fuel pressure regulator (16) Back of camshaft gear (17) Speed/timing sensors (18) ECM (19) Boost pressure sensor. The Caterpillar C7 Engine was produced from 2003 - 2009 and was originally touted to be the greatest CAT Engine ever made. However, things don't always go according to plan. Read about the history and technical specs of this legacy engine. The C7 from the factory has the crankcase breather on the side of the block, next to the cam followers. (A location inside the engine where there is a lot of splashing - This complete breather assembly was blocked off, so it no longer functions. The new engine breather is mounted on the top of the valve cover, where there is no oil splashing. Cat c7 diesel engine belt diagram the c71 acert 7 liter six cylinder engine meets tier turbocharger poly vee belt and hydraulic tappet adjustment minimize the need for routine service clean emissions module cem incorporates a the d6n is powered by a cat and engine valve lash adjustment is not required saving time effort and cost.