Thread Repair Tools / Inserts

TIME-SERT J-42385-500BS BIG SERT Northstar Head Bolt Thread Repair M11x1.5

TIME-SERT J-42385-500BS BIG SERT Northstar Head Bolt Thread Repair M11x1.5 image

Product #: J-42385-500BS


Your Price: $571.13


Product Description

Includes Free Shipping. The TIME-SERT Big Sert (Oversized) J-42385-500BS head bolt thread kit for 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 GM Cadillac Northstar engines with the very common size M11x1.5mm (11 millimeter by 1.5 millimeter) head bolt size.

The tooling for the J-42385-500BS has adjustable depths so the different depths of holes can be serviced. This allows the J-42385-500BS head bolt thread repair kit to be used on a wide range of Northstar engines. It's important to be cautious NOT to over drill the depths in the engine block. See the video linked above for more information on how to use the thread repair kit.

*Note The J-42385-500BS is for an "oversize" repair which means a previous repair insert, like a failed Helicoil or another type, had been used before. The 'BS" at the end of the tool number stands for Big Sert. Big Sert is the manufacturer's designation for over-size. Just the outside diameter is larger so the Big Serts accept the original size head bolts.

Steel bushing type inserts (part number J-42385-507BS) are used which are ten times stronger than steel. The kit comes with a quantity of 10. The block takes a total of 20 inserts so it's important to purchase 10 more inserts to have enough to repair the whole block. Since the outer diameter is larger the alignment dowels for the head need to be larger as well. The kit comes with two alignment dowels. If fixing all holes in the entire block (all twenty) two more alignment dowels will be needed part number J-42385-508BS.

The original TTY (Torque to Yield) head bolts are used which allow proper clamping just like the engineers at GM had in mind. That's why GM does NOT recommend aftermarket studs that have cropped up on the market recently. TIME-SERT standard size is the ONLY recommended repair for the Northstar. BIG SERT is the alternative to discarding a block when a regular size insert like a Helicoil has failed.

Time Sert J-42385-500BS Head Bolt Thread Repair Kit Includes:

Qty Tool Item Number

1 Fixture Plate 56111

1 Drill Bushing J-42385-302BS

1 Alignment Pin J-42385-303BS

2 Bolts, Short J-42385·503

2 Bolts, Long J-42385-604

1 Step Drill J-42385-2006BS

1 Tap J-42385-2007BS

1 Insert Driver J-42385-2008

1 Stop Collar J-42385-2017BS

1 Loctite 6020

2 Dowel J-42385-508BS (used on corner holes 4 total needed for entire block)

1 Driver Oil J-42385- 110

10 Big Sert Inserts J-42385-507BS (20 total needed for entire block, 10 per side)

1 Laminated Instruction card.

*Note TTY head bolts should be replaced as per auto repair manual. Reusing old head bolts can cause repeat thread and/or head gasket failure.

Cadillac Northstar Engines - A total of 20 inserts are needed for the Northstar engines if repairing entire block.

  • 95, 96, 97, 98, 99, 00, 01, 02, 03
  • Cadillac Deville 4.6 L 281 CID V8 DOHC 32 Valve Northstar 1995-2003.
  • Cadillac Eldorado 4.6 L 281 CID V8 DOHC 32 Valve Northstar 1995-2003.
  • Cadillac Seville 4.6L 281 CID V-8 DOHC Northstar 1995-2003.
  • Oldsmobile Aurora 4.0 Liter 243.8 CID V8 Double Over Head Cam 95-99
  • TIME-SERT is Tested and approved by GM. 

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