REPAIRING THE ENGINE FRAME OR BLOCK

REPAIRING THE ENGINE FRAME OR BLOCK

Some engine block repairs are cost efficient, while others are not. The following paragraphs briefly discuss basic repairs to the block itself. Later paragraphs discuss repairs to block components.

LEAKING WATER JACKET
Most engine blocks that have a leaking water jacket are not worth the cost to repair. To determine if such a block can be repaired economically, consult the appropriate MILSTD and technical manuals for the engine.

WARPED CYLINDER BLOCK OR CRANKCASE FLANGES
You may use a hand surface grinder to correct small amounts of surface warpage. Do not remove more metal than necessary. The manufacturer’s manual will specify how much metal you may remove with the hand grinder. If the warpage exceeds the maximum allowed for hand grinding, send the block to the machine shop for machine grinding.

WORN BOLT HOLES
Over a period of time, bolt holes may become oversize due to wear from threading and unthreading the fasteners. You may correct a worn bolt problem by one of three primary methods, depending on the situation.
1. If the bolt hole is slightly oversize, you may be able to simply use a larger bolt in the hole, if such use is authorized for the component the bolt fastens down.
2. If enough metal remains around the hole, you may be able to install a helicoil. Check the helicoil installation instructions and appropriate technical manuals to determine whether or not a helicoil is acceptable.
3. You may also till the hole with weld metal and then drill and tap a new hole.
Whatever method you use to correct the problem, always check the bolt and bolt hole for proper fit.