Is your local machinist your BFF? If he saves your cracked block, he better be on your Christmas card list.

1. How To Repair Cracked Block Water Jacket
2. How To Repair Cracked Block On Boat Motor
3. How To Repair Cracked Block Walls

Is Your Local Machinist Your BFF? If he has cracked engine block repair skills, He Better Be On Your Christmas Card List!

Metalink Cracked Engine Block Repair Kit. A cracked engine block can be returned to service using Metalink ML400 Machinable Repair™ Compound and affecting the following procedure. 1) Prepare surface in accordance with Metals Preparation Guide.Clean and abrade the area around the crack at least 2” on all sides. How to Repair a Cracked Engine Block. Identify the crack with your three-part penetrating dye system. First, spray or paint your penetrating dye over the suspected crack and the surrounding area, then wait 5 minutes. Spray the dye-cleaner on a lint-free cloth and clean all of the dye off of the surface of the block. A cracked cylinder head or engine block may or may not be bad news depending on the size and location of the crack(s), the value of the casting and what it will take to fix the crack(s) versus what it would cost you to replace the casting. A relatively common casting that is badly cracked is.

Engines endure much abuse. Sometimes this torture results in damage to either the block or the heads–or both. The block can be very rare, such as a matching-number block for an LS6 Chevelle or the original casting for a Z/28 or an unusual 409 engine. In our case, the block is not necessarily rare, but it certainly is valuable and worth pursuing cracked engine block repair. While assembling a brand-new Dart Little M block, the unexpected happened, and assembly oil found its way into the bottom of one of the blind cylinder-head boltholes. Production small-block Chevy head boltholes are open at the bottom of the water jacket, which often allows coolant to seep up the threads unless thread sealant is used. The Dart team that designed the Little M block eliminated this hassle by ensuring these head boltholes were sealed. This requires the engine assembler to be careful not to allow any liquid to find its way into the holes. If that happens, the liquid in the bolthole can create a hydraulic-lock situation when the assembler torques the head bolts, which is what occurred during this engine’s final assembly. Accidents happen, but this one was catastrophic. One of the cylinder head bolts hydraulic-locked, cracking the deck surface. But its close proximity to the two center cylinders allowed the crack to migrate in both directions into the cylinder walls. As you can imagine, this created quite a problem. Not only did the one head bolthole require cracked engine block repair, but now two cylinder sleeves were also needed.

We called our friend Don Barrington at Barrington Engines in Van Nuys, California, a cracked engine block repair expert, to get an idea of what would be required to put our block back into service. Barrington said the block could be repaired, and we thought it would be a good idea to chronicle the process so you can see how a qualified machinist resurrects a major fissure. Here are the major steps involved with sleeving a pair of cracked cylinders.

A cracked engine block might seem like an absolute disaster for your car. As the engine block is one of the most vital components of your vehicle, a damaged block can create numerous problems and consequences. If you see signs that your engine block is cracked, you have some options, so don’t worry that all is lost. There are methods by which you can repair the block using welding, chemical sealants, or epoxy and stitching kits.

Step 1 - Prepare the Block

The engine will very likely have to be removed, so be prepared to do this. It is not an easy job and it takes quite a serious amount of dismantling of parts and components to get the block out. You might also require a hoist. If the engine block is already removed you can proceed to fix it.

Step 2 - Assess the Crack

How deep or long the crack is in your engine will determine the best way to fix it. It will also determine whether it can be fixed. Cast iron is not easy to weld and it takes a very skilled person to mend a cast iron engine block with welding equipment. If the crack is less than 8 inches long and less than 1/8 of an inch wide, it is very probable that you can fix it with a metal stitching kit and epoxy.

Step 3 - Clean the Wound

How To Repair Cracked Block Water Jacket

The crack needs to be completely clean before you proceed any further. Use the wire brush to clean the crack and ensure there is no residue grit, grime, or dirt in and around the crack. If the crack is too wide to use the brush then just wipe it clean with a damp cloth and use a tag-rag. Even the most minute pieces of grit or dust can cause issues with the cylinders, so do not let any get inside the crack.

Step 4 - Stitch the Wound

How To Repair Cracked Block On Boat Motor

Take a 'stitch' from the kit and insert it into the crack with the hammer. Depending on the type of kit you buy, your stitch may or may not have 'shoulders.' The shoulders help you to hammer the stitch deeper into the crack for better adhesion and a cleaner finish. Other stitches might be equipped with break-off grooves that can be taken off at a predefined place, once inside the crack with the torque wrench.

Step 5 - Use Epoxy

How To Repair Cracked Block Walls

Use an epoxy compound suitable for engine block repair. With the stitches in place, apply the epoxy into the crack as far as you can put it and then fill the crack completely. Cover over the surface and smooth the epoxy for a neater join. Leave it to dry thoroughly for however long the recommended time states on the instructions. Your engine block should now look and be as good as new. As a final word of caution, always be sure that what you are doing is the correct procedure and do not attempt this if you are uncertain.