Cummins ISX11.9 CM2250 – Service Manual 017-011   Straight Thread Plug

Select the appropriate size allen wrench or socket, and remove the plug.

Inspect the threads of the pipe plugs for mutilation or other damage.

Inspect the threaded bores for damage.

Repair the bores, if necessary.

Use spray cleaner, Part Number 3823717 or equivalent, to clean the threads of the straight thread plugs and threaded bores.

Inspect the threads of the pipe plugs for mutilation or damage.

Inspect the threaded bores for other damage.

If the threaded bores are damaged, repair the threads according to the Repair section in this procedure.

Four different types of thread inserts can be used to repair damaged capscrew threads:

1. Coiled thread inserts
2. Keylock thread inserts
3. Open end thread inserts
4. Closed end (blind) thread inserts.

Coiled thread repair inserts have the following advantages:

• Can be installed in locations that have minimal thickness around the threaded hole
• Made of materials that resist and prevent galvanic action
• Sealants are not required when installing repair inserts
• Equivalent to or exceeds the strength of the original threads
• Finish machining is not required.

Coiled thread repair inserts have the following disadvantages:

• Special sized tap drills or reamers are required
• Special taps are required
• Special installation tools are required
• The repair insert can not be reused it it “backs out” after installation
• The coiled thread insert has no bottom and provides no sealing capabilities.

Keylock thread inserts have the following advantages:

• Standard, commercially available, drills and taps are used during installation
• Relatively inexpensive and available from several sources
• Can be removed and replaced without requiring modification or rework to the component.

Keylock thread inserts have the following disadvantages:

• Generally apply to repair of components that have thicker wall sections
• Installation requires a locking key driver.

NOTE: Inserts can be used in cast iron, steel, copper, brass, bronze, aluminum, magnesium, plastic, and wood.

For special installations, call or write the following manufacturers.

NOTE: This part of the procedure is for repairing coiled thread inserts.

This repair procedure provides useful information and installation instructions for coiled thread inserts. Coiled thread inserts are a precision wound wire insert for repairing failed or mutilated internal threads.

These coils in their free state are designed to be larger in diameter than the tapped hole. After installation, the insert conforms to the outer wall of the tapped hole. This compressed fit holds the insert in place.

NOTE: Inserts are normally made of stainless steel wire. However, other materials are available to meet special installation requirements.

Determine the diameter, depth, and pitch of the original threaded hole.

WARNING  To avoid possibly eye damage, always wear protective goggles when drilling metal.

Use cutting oil while drilling the capscrew hole to the specified diameter. Use the charts in this procedure for drill size diameter specifications. Drill to the bottom of blind capscrew holes.

Use the special tap specified in the chart, according to the thread size needed, to cut the threads in the capscrew hole.

NOTE: Use cutting oil when tapping the capscrew hole. Clean the capscrew hole before installing the repair insert.

Use chip removing unit, Part Number 3164019, to remove machining chips from the capscrew hole.

Select the type of installation tool required for your specific thread insert and space limitations.

Install the repair insert into the prepared hole. The top of the insert must be 1/4 to 1/2 of a thread below the surface of the part.

Break the installation tang off of the thread repair insert. Position a punch or screwdriver near the free end of the installation tang. Strike the tool to break off the tang.

Remove the installation tang from the repaired hole.

NOTE: This section of the procedure provides guidelines for using keylock inserts.

Keylock inserts can be used to repair threads in cast iron, steel, and aluminum components.

Thread repair kit, Part Number 3375021, contains keylock inserts. The inserts are internally and externally threaded metallic cylinders which have captive locking keys. The keys prevent the insert from rotating after it has been installed.

Determine the diameter, depth, and pitch of the original threaded hole.

WARNING  To avoid possibly eye damage, always wear protective goggles when drilling metal.

Use cutting oil while drilling the capscrew hole to the specified diameter. Use the charts in this procedure for drill size diameter specifications. Drill to the bottom of blind capscrew holes.

NOTE: The drill must be in proper alignment when drilling the capscrew hole.

Countersink the hole to the diameter specified on the chart. The correct angle is 82 to 100 degrees.

NOTE: Use cutting oil when countersinking the capscrew hole.

Use chip removal unit, Part Number 3164019, to remove any debris from the hole.

Use cutting oil to tap the hole to the correct diameter, pitch, and depth.

Tap size and depth information is included at the end of this procedure.

Use a spray cleaner to clean the oil from the capscrew hole and flush the newly cut threads.

WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

Use chip removal unit, Part Number 3164019, to remove any debris from the hole.

Dry the threads with compressed air.

Install the insert into the prepared hole.

Turn the insert clockwise until the insert stops at the specified depth.

Put the staking tool over the insert. Slide the sleeve of the tool over the keys.

Use a hammer to strike the installation tool until the keys are driven down to their full depth.

Remove the tool.

The repair is now complete.

Inspect the area around the threaded hole that is to be repaired.

Remove any burrs from the surface. A flat mill file is very effective for this process. Burr removal is necessary so an accurate fixture location can be obtained.

WARNING  Wear approporiate eye and face protection when drilling metal. Flying debris and dirt can cause personal injury.

Use a cutting oil when drilling the damaged threads to the specified diameter and depth dimensions for the specified repair insert. A listing of installation requirements is included in this procedure.

Use chip removal unit, Part Number 3164019, to remove any debris from the hole.

Use cutting oil. Tap the hole for the repair insert. The correct thread depth will allow the insert to be installed 0.0 to 0.25 mm [0.00 to 0.010 inch] below the surface of the component.

Measure the insert and compare the measurement to the data sheet contained in this procedure for insert lengtth specifications.

Use a spray cleaner to clean the oil from the capscrew hole.

Flush the newly cut threads.

WARNING  Wear apprppriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

Use chip removal unit, Part Number 3164019, to remove any debris from the hole.

Dry the threads with compressed air.

Obtain a capscrew and nut with the same size threads as the insert inside diameter.

Install the nut and insert on the capscrew.

Use a spray cleaner to remove the preservative coating from the outlside diameter of the insert.

Apply four beads of sealant, Part Number 3375068, to the outside diameter of the insert.

NOTE: The beads of sealant must be about 0.8 mm [1/32 inch] wide and spaced 90 degrees from each other.

Install the repair insert.

The insert must be 0.0 to 0.25 mm [0.00 to 0.010 inch] below the surface.

Loosen the nut and remove the capscrew.

Make sure the inside portion of the repair insert is clean. Remove any file shavings or debris.

Allow the sealant to cure for 15 minutes before use.

NOTE: This part of this procedure applies to Closed End “Blind” Inserts.

This part of the procedure provides the instructions for installing closed end “blind” inserts.

The charts contained in this procedure lists the two types of blind inserts.

• SAE internal and external threads
• Metric internal with SAE external threads.

Closed end inserts are generally used in cases where the bottom or side of a hole has been pierced. They can be used to repair any kind of hole or thread, if desired.

NOTE: Closed end inserts can not be used to repair top deck cracks that run into cylinder head capscrew holes.

Obtain the required reamer or drill size for the hole to be repaired. Use the charts contained in this procedure for size specifications. Install it in the drill.

Set the drill depth by placing the insert to be installed between the top of the hole and the drill chuck.

NOTE: If the drill is too long, make a mark on the drill bit to indicate the correct depth.

WARNING  Wear approporiate eye and face protection when drilling metal. Flying debris and dirt can cause personal injury.

Use cutting oil. Drill or ream the hole to the proper depth.

NOTE: In some cases when using a drill, the proper depth will pierce the bottom of the hole.

Use chip removing unit, Part Number 3164019, to remove machining chips from the capscrew hole.

Use cutting oil. Tap the hole to the required depth. Use the charts contained in this procedure for tap sizes.

NOTE: The correct depth will allow the insert to be installed flush, to slightly below the surface.

Use a spray cleaner to remove the oil film and clean the newly cut threads.

Use chip removal unit, Part Number 3164019, to remove any debris from the hole.

WARNING  Wear appropriate eye and face protection when using compressed air. Flying debris and dirt can cause personal injury.

Use compressed air to dry the threads.

Obtain a capscrew and nut with the same size threads as the insert inside diameter.

Install the nut first, then the insert on the capscrew.

NOTE: The nut should have a straight shoulder which, when installed against the insert, will allow the insert to be installed slightly below the surface.

If a nut is not available, it is acceptable to bottom the capscrew out in the insert for installation.

NOTE: This type installation will require time for the sealant to set up before removing the capscrew from the thread insert.

Use a spray cleaner to remove the preservative coating from the outside diameter of the insert.

Apply four beads of sealant, Part Number 3375068, to the outside diameter of the insert. The beads of sealant must be about 0.8 mm [1/32 inch] wide and spaced 90 degrees from each other.

Install the repair insert.

Loosen the nut and remove the capscrew.

NOTE: If a capscrew without a nut was used, allow 10 minutes for the sealant to cure before removing the capscrew.

The insert should be flush to slightly below the surface.

Allow the sealant to cure for 15 minutes before use.

Clean the insert threads to remove any debris.

Install a new o-ring on the plug. Lubricate the o-ring with clean 15W-40 oil.

Install and tighten the plugs.

Use to the following chart for torque values.

Tighten straight thread plugs to the appropriate torque value.