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Also Importers of KEENSERT Type Thread Inserts, E-Z lok, Helicoil, Big-Sert, Loc-in-Sert and Thread Inserts for Plastic and Wood

TIME-SERT® is a thin wall, solid bushing, self-locking insert with positive placement.

TIME-SERT® inserts are a thin wall solid bushing insert. This guarantees easy installation and allows for full load use of tapped hole, ensuring protection against stress and vibration.

TIME-SERT® inserts are “timed” internal to external which gives a very thin wall thickness which means TIME-SERTs can be installed in areas of limited space and clearance.

TIME-SERT® being a solid bushing insert gives it added strength and easily withstands high temperatures without damage or deforming. TIME-SERT® inserts have no prongs or tangs to break off or deal with down in the hole, which can be a problem in deep holes.

TIME-SERT® inserts are self-locking having an actual locking feature which will prevent them from coming out when a bolt is removed. On installation the bottom few internal threads of the insert are cold rolled to expand into the mating external threads of the base material locking the insert in place.

TIME-SERT® inserts have a flange, which will give them a positive placement on installation for “accurate specific depths”. This ensures that the insert does not wind down into the threaded hole.

TIME-SERT® inserts are used in Aluminum, cast iron, steels and even some hard plastics.

The tool kits listed are the “Internal size”.

Metric Example: If your bolt is M6x1.0 and your stripped thread is M6x1.0 you will need a M6x1.0 thread repair kit.
Inch Example: If your bolt is 3/8-16 and your stripped thread is 3/8-16 you will need a 3/8-16 thread repair kit.

TIME-SERT® inserts are made from 12L14 carbon steel and 303 stainless steel.

Click links for material specifications in PDF format.

12L14 Carbon Steel

303 Stainless Steel

2024 T351 Aluminum

Stainless steel is recommended for the medical or food industry, in water applications or where there may be exposure to the elements, such as in disk brakes.

Yes TIME-SERTs® can be installed in blind holes.

As a basic guide, the hole should be 0.25 inches or 6.3mm deeper than the insert length, or a depth equivalent to the relief angle of the tap, which may vary depending on the size of the tap. The relief angle is the length from the tip of the tap to the first “full” thread. This allows the tap to cut a full thread for the insert length.

The extra depth also allows the insert driver to pass fully through the insert to expand the last few threads, thus completing the locking action.

Another thing to keep in mind when repairing a blind hole application is that you DO NOT want to bottom out the driver tool on installation. To prevent this, simply place the driver tool into the hole before commencing installation and mark the tool at the point it can’t enter any further. You can use an ink marker or strip of electrical tape around the driver for this.

TIME-SERTs can be removed with a spiral point screw extractor or drilled out with the drill that came in the repair kit.

It is not recommended to use ez-outs or screw extractors on BIG-SERTs because the locking pin at the bottom of BIG-SERT will create a cam lock effect. You should drill out BIG-SERTs.

Yes, if the threads in the base material are not damaged a new TIME-SERT® can be re-inserted into that hole. This is a common practice on CNC pallet changers. When an insert starts to show wear over time, the insert can be removed with a screw extractor then replaced with a new one.

The standard TIME-SERT® carbon steel inserts ” Black in color” are plated with Zinc Phosphate. Sparkplug washer seat inserts are plated with a copper flash good for heat and anti-seize properties. Sparkplug taper seat inserts are silver plated.

TIME-SERT makes no claims on torque specs or pullout, nor do we provide them. The reason for this is there are many factors that can determine the end result of the insert thread strength.

One major consideration is the installation process:

  1. Was the insert installed correctly using Time-Sert tools and square to the hole? This has a huge effect on the outcome of the torque specification.
  2. The type of material the insert is being inserted into. Plastics will not have the same torque values as aluminums, steels, or cast irons.
  3. The length of the insert. Inserts must match the length of the bolt threading into the hole. Too short an insert length could result in thread failure.

TIME-SERT® states that if the thread repair is done correctly and with the proper length of insert used for the application e.g. the insert is the same length as the original thread engagement, the result should be a hole that matches the original torque specification of the hole. Customers have found in their own testing data that TIME-SERTs have exceeded their expectations.

Yes, sparkplug repairs can be done without removing the head by placing a heavy grease on the step tap flutes to catch the chips. TIP: Mechanics have mentioned that using a shop vac with a plastic tube taped to the nozzle end works well for removing any stray chips left over.

What type of sparkplug do you have: Washer seat or Taper seat? Washer seat sparkplugs will have a washer to seal the sparkplug against the head. Taper seat sparkplugs will have a taper to seal against the head.

Measure from either the sparkplug (washer) or (taper) to the last thread. (Not to the end of the electrode.) This will give you the correct length of insert. TIME-SERT® inserts cannot be shortened in length. Please refer to the TIME-SERT® catalogue or the sparkplug size listing on this site for length of inserts. Go to Sparkplug Size Listing

The diameter of the sparkplug will be the size. The threads or pitch will be a standard for the diameter. Example if the diameter is M14 the standard pitch will be 1.25 or M14x1.25.

If you can provide the sparkplug number or make, model, year, litre of vehicle we can give you a part number for the kit and insert required.

No, you cannot repair a stripped Helicoil with a TIME-SERT®, as they have the same outer diameter. You will need to use a BIG-SERT®, which is an over-sized version of the TIME-SERT®. Please refer to the BIG-SERT® catalogue or web page for sizes available.

Normally if the hole is just stripped out and has never been repaired a TIME-SERT® will repair that hole. You can also check the drill size from the online TIME-SERT® catalogue or go to the engineering data page. The drill size should be slightly larger than the stripped out hole.
Engineering Data
Metric Engineering Data
If the hole is bigger than the tapping drill size, refer to our Big-Sert® line for oversized holes.
Bigsert Size Tables

No! You cannot cut off the bottom or top of the inserts. The flange at the top is required to give the insert a place to sit for positive placement. Removing the bottom of the insert will destroy the locking action produced by roll-forming the final threads.

One possible solution. The hole being repaired has a depth shorter than the length of our shortest insert. There are a few cases where we do not have a short enough insert for a particular application.  For example: trying to repair a hole 5/16-18.  Our shortest length insert is .350 inches.  If you have a hole depth of .250 inches deep, you can install a TIME-SERT® without using a counterbore, leaving the shoulder sticking up to be removed later by milling or filing.

The steps to perform this type of installation are: 1) Drill hole (2) tap hole (3) let insert set up with loctite (4) install insert (5) file insert flush.

The following points are to be noted:

  • After drilling the hole out, “DO NOT” use counterbore tool, simply tap the hole.
  • On installation screw the insert into the hole with loctite to the desired location.
  • Let the insert set up with the loctite before running the insert driver tool through the insert. The loctite will prevent the insert from going too deep into the prepared hole.
  • Use the driver tool to expand the last few threads of the inserts.
  • The insert will now be protruding or sticking up higher in the hole. You will have to “file down” or mill the top of the insert to get the insert flush with the surface.
  • It’s recommended to run the insert driver back through the insert to clean any burrs at the top of the insert.
  • The repair is now complete.

Yes, TIME-SERT® inserts use STI taps which are considered special.

STI stands for “Screw Thread Insert”. As an example, a TIME-SERT® M8x1.25 repair kit would require a M8x1.25 STI tap. This is “larger” than a standard M8x1.25 tap.

STI TAPS are a mathematical formula from a nominal size thread.

STI Basic P.D. = Nominal Thread O.D (Basic Major Dia.) – Basic P.D. + Basic Major Dia.

Example for a “1/2-20” STI tap:

STI “1/2-20” O.D =.500 Dia. – P.D .4675 + O.D .500 = .5325 STI Basic P.D

Taps are generally class 3 (4H limit)

TIME-SERT® taps are made from M2 high speed tool steel.

What is happening is the plating is slightly heavier on some inserts. That is why it will feel tighter when screwing inserts onto the driver tool by hand. This is common on all inserts. If some of your inserts only screw onto a few threads of the driver tool, don’t worry as the driver tool will screw through the insert fine when installing. Of course, always use oil on driver tool when installing inserts. This can be a 30wt motor oil.

Yes, Loctite may be used on the external threads of the insert. Due to the solid wall design there is no danger of it passing through the threads of the insert and locking up the bolt as in coil types.

TIME-SERT® would recommend repairing, at the very least, all the holes on the side of the block where the threads have failed. (If repairing a V engine)

If repairing a straight or in line engine block TIME-SERT® would recommend repairing all holes.

The reason for this is simply the weakest link effect. If you only repair the bad hole or holes and leave the others there is a very good chance the other non-repaired holes may fail.

Especially with aluminum blocks these days and over-heating you can experience an anneal effect where the material becomes brittle. The only way to safeguard against this is to remove all the old threads by replacing with steel inserts.

TIP: Clear packing tape

One last tip we like to mention is using clear packing tape normally used to close cardboard boxes. If you tape across all the holes on top of the cylinder block this will help keep all chips from entering the water jacket and piston holes. This way when the repair is finished you can easily remove the tape from the top of the block and be assured that no chips have entered. The clear packing tape is very thin and won’t be a problem pushing through the alignment bolts included in the head bolt repair kits when starting the repair.

Possible solution to remove a broken driver that is flush to the surface. If the install driver is flush to the surface try to find a nut that is close to the driver size.  Place the nut over the broken portion.  Using a wire welder tack the nut to the tool, then back out the driver.

NOTE: Use caution and try to not bend the tool over or bottom the driver tool out in the hole. We suggest using a tap handle wrench when installing inserts. If using a 12-point socket on a ratchet, center the palm of your hand over the square of the tool to keep the pressure centered when turning the driver tool.

Use Time-Sert driver oil p/n 6010 or 30 wt motor oil on the external threads of the driver when installing inserts (NOT on the outside of the inserts).