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TIME-SERT 1015CORE Rocker Bolt Hole Thread Repair Kit M10x1.5

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2.00 LBS
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This thread repair kit is for rocker arm bolts on some GM 3.1 and 3.4 liter engines that have 10mm bolts. If the 8mm repair is needed see the 1812CORE. *Note this is for a first time repair, meaning that there was no other repair kit used like a Helicoil or other competitive brand used previously.

The core drill included will allow a 11mm length insert to be installed deeper than the standard kit.

M10x1.5 kit includes: Coredrill, , tap, driver, tap guide, 5 inserts 11mm length. The mechanic doing the repair will have to set the counterbore depth manually by hand. 

This tooling has been used in rocker arm thread repair where the threads must start a few millimeters deep below a "Slot". This kit is for "first time" repairs which means Heli-Coils or a different competing brand, were not used  previously.

The core drill countersink combination will have to set by hand.
We use this special 4 flute core drill because it makes drilling
thru a slot easy. Using a traditional 2 flute is difficult because the drill
it wants to hang on the slot and break.

pdficon-small.png Click the following for the 1015CORE instructions pdf.

1. Step Core Drill w/collar

2. Tap

3. Insert Driver

4. Tap guide

5. Inserts

*Note, some GM engines use use a 8mm rocker arm bolt. Please verify your bolt size before ordering.  A 1812CORE metric thread repair kit may be needed if your size is M8x1.25mm.


Question - Since the head of the bolt on my engine takes a 10mm socket, does that mean I have a 10mm bolt?


Answer - No, not necessarily. The head of the bolt does NOT indicate the diameter of the bolt itself. When measuring metric bolts with a digital micrometer the bolt diameter of a 10mm bolt will read around 9.8 (just under 10mm). If measuring an 8mm bolt diameter the digital micrometer reading will read approximately 7.8mm. That's just under it's designated size. 

Question - Is there a 1015CORE in a Big Sert (oversized) kit?

Answer - No. There has not been enough demand at this time to make a 1015CORE BS. The main difference in a kit for this particular application is in the number of flutes in the Reamer (also called a core drill bit). Time Sert uses a four flute core drill bit because it's almost impossible to drill in a hole that has a slot (the slot is for the rocker arm alignment) without it catching and breaking. The two flute drill bit will snap because it does not have 4 points of contact. Time Sert does offer an M10x1.5 BIG-SERT kit, but it has the standard two flute core drill bit so it may break in this application. Therefore, it's totally our customer's risk. If the head is off the car and drilling can be done with a drill press (or milling machine), it would be less likely to break with the standard Big-Sert kit. We offer a Big Sert kit p/n 5015G. .            But again as mentioned, drilling the hole with a 2 flute drill through a slot is a huge problem unless the drill is supported in a mill machine.

Mouse over the images above for a more detailed view of the kit components. Also notice our bulk discount prices on TIME-SERT replacement inserts for thread repair kits. Need more information on TIME-SERT thread repair kits? Visit our auto repair blog section on thread repair kits for tips, advice and all your thread repair questions answered. Just comment and we will be quick to respond.

See the pdficon-small.png TIME-SERT products pdf for more information on thread repair kits and inserts. Some are listed for certain applications on cars, trucks and motorcycles. The pdf is a partial application list so feel free to email or call if we can assist with your particular need. We also accept inquiries regarding our daily TIME-SERT specials. Remember TIME-SERT is recommended by leading car manufacturers like the General Motors Corporation. In fact TIME-SERT is GM's only authorized repair for head bolt threads.

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2 Reviews

  • 5
    Great thread repair system

    Posted by Randall V on 18th Sep 2015

    I say system because a lot of thought and designing went into this thread repair kit. Much better than a Helicoil or any other thread repair I considered purchasing. Now the threads are stronger than new for my rocker arms. In fact I did all of them to prevent having problems with any of the others in the future. Thanks Wise Auto Tools!

  • 3

    Posted by Chad on 30th Jul 2014

    A lot of money out of my pocket and it did not fix the problem. For the money I'm out I could of replaced the engine.

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