Cat D3K starting problem

S# FFF00174

This machine is hard to start, especially when it sits overnight. It will start without ether but it can take up to 60 seconds before it cranks up. I have good fuel flow, replaced the hand primer ( which is part of the filter base). No visible leaks or loose connections.
Once the engine starts, it runs great and has its normal power with no excess crankcase pressure or flow, normal smoke from the exhaust.. It almost seems like the long cranking is helping the system build...

Cat D3K starting problem

Cat D3K starting problem