Ford AT4Z-6250-A Camshaft

Confirm that the crankshaft is still positioned at TDC and that the timing pin is in place.

Rotate the camshafts to position the dowel pins in their proper positions for installing the VCT units and secondary timing chains.

The steps for removing the camshaft include removing the pushrods, valve lifters, timing chain, camshaft sprocket, and possibly the radiator and air conditioning condenser. Then, check the camshaft end play, slide off the balance shaft drive gear, remove the thrust plate bolts, and carefully pull the camshaft out.

Two special camshaft holding tools (manufacturer tool no. 303-1248) are required.

13. Inspect the rocker arms for signs of wear or damage. 14. Examine the camshaft lobes for scoring, pitting, galling, and evidence of overheating. Replace the camshaft if any such wear is evident. 15. Calculate the camshaft lobe lift by measuring the lobe height and the diameter of the base circle of the lobe. Subtract the base circle measurement from the lobe height to determine the lobe lift. Replace the camshaft if the lobe lift is less than specified. 16. Inspect the camshaft bearing journals and the cylinder head bearing surfaces for pitting or excessive wear. Replace the component if any such wear is evident.

These models are equipped with Direct Injection (DI) and a high-pressure fuel pump. Fuel pressure in the high-pressure system on DI systems is under extremely high pressure. Be sure to correctly perform the fuel pressure relief procedure prior to servicing any of the high-pressure fuel system components to prevent injury.

The remainder of the reassembly procedure, including replacement of the timing chain and setting the valve timing.