Helpful check-list to follow when installing your head
Installing a new or remanufactured cylinder head is easy if you follow this checklist:
- Check head and block for flatness with a straight edge and a feeler gauge. The maximum warp should be 004 across the block’s deck and 002 across the head.
- While the head is loose, check the spark plug hole or injector hole threads and retap as necessary.
- Inspect the finish of the head; if possible, borrow a friend’s profilometer to check for smoothness.
- Run a thread chaser through each cylinder head bolt hole, blow out with compressed air and wipe all surfaces clean with a solvent.
- Bring the Number 1 piston up to Top Dead Center (TDC) using a dial indicator. This may facilitate timing later.
- Install the head gasket correctly, front-to-rear, and in the upright position. Align the dowel holes into the dowels.
- Apply teflon thread sealant to any head bolts entering the water jacket. Lightly lube the other bolts with an assembly oil. (We use a mixture of STP and SAE 40).
- Tighten the head bolts following the procedures specified in Foley Tech Tips 10 and 30. (Bolts are inexpensive. We supply new bolts to most of our diesel customers who don’t know the history of their head bolts and fear they have been overtightened and stretched in the past. Some people use a gauge from Precision Measuring Service in Texas to measure the bolt stretch.
With a clean, straight, correctly finished head now in place and sequentially torqued down, we can focus now on the remaining part of the valve train. Carefully oil the push rods, especially the tips, and insert into the head. Install the rocker arms, ensuring the rocker tips are aligned with the pushrod tips. Then adjust your rocker arms once installed.
Written by Dr. Diesel
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