GM 2.8, 3.1 & 3.4 Stripped Threads – TIME-SERT 1812CORE

12:36 pm Chevrolet, GM Intake, How To Auto Repair, TIME-SERT Kits Summary: Suggestions on how to properly repair stripped threads for rocker arm bolts in cylinder heads. Tools for repairing rocker arm bolt holes for gm 2.8, 3.1 and 3.4’s. Affected engines in GM vehicles are 2.8, 3.1 and 3.4 Liter V-6 motors. Aluminum cylinder heads used in Chevrolet, Oldsmobile, Buick and Pontiac’s have a common problem with rocker arms coming loose. Misfire codes and very rough running conditions can indicate a fallen rocker arm.

Here’s the common scenario; After replacing the intake gaskets yourself or having a repair shop do the job, the engine starts running horribly! The check engine light comes on and there’s an OBVIOUS misfire. What’s the most common cause? A fallen rocker. ONE bolt holds each rocker. The bolt threads into the aluminum head. There’s a lot of stress on these threads and that’s why they commonly fail. We have an article that covers using a pushrod remover tool that eliminates the need to run these bolts in and out to begin with, which is the best way to avoid wearing these delicate aluminum threads.

The next step is to either replace the cylinder heads or repair the threads. The least expensive repair would be to just repair the threads. The next decision to make is “what repair system to use?” Heli-Coil thread repairs are a popular choice, however any experienced auto technician, if given a choice would go with the TIME SERT brand part number 1812CORE DLT. Need more information? See our article on the difference between Helicoil and Time-Sert before you decide. It’s linked below with the other related pages including the Time Sert thread repair kit.

Related Articles

Time-Sert 1812CORE Metric 8 x 1.25 mm Thread Repair Kit

GM 3.1 and 3.4 Intake Gasket Replacement Tips

TIME-SERT VS HELI-COIL What’s the difference?

3 Responses
  1. Bill :

    Date: August 7, 2014 @ 7:46 pm

    time sert 1812 core.
    Just wondering if this is the proper fix for a stripped out rocker arm bolt. I saw a video by Cadillac Northstar mechanic complaining these inserts only last about 12k miles especially on the head bolts. Is it worth using for a stripped rocker arm bolt hole? Will the repair last?

  2. Bill :

    Date: August 7, 2014 @ 7:48 pm

    Forgot to mention the engine I will be using this Time Sert kit on is a 99 3.1 engine rocker arm stud hole.

  3. dennisb - Auto Tool Sales :

    Date: August 8, 2014 @ 7:11 am

    Bill, the only other repair that I’m aware of for the GM rocker arm bolt hole, aluminum thread repair is a Helicoil. The Heli Coil is a thin coil of wire. The Time Sert 1812CORE uses a solid carbon steel insert. We also have the 1812COREBS which is the oversize kit. It is possible that the aluminum in the head that the insert goes into will fail, especially if the insert was not installed properly, but I’ve never heard of either the regular or the oversize carbon steel insert itself failing. Your other option is to replace the expensive cylinder head (with related gaskets, extra labor etc) and have the weaker aluminum threads again like failed to begin with from the factory. As far as the Time Sert NorthStar Head Bolt repair kit, see the following article for more information TIME-SERT Insert VS NorthStar “Stud” Type Repair Kits.

Comment Below, Please Unlock Caps

Tell us your thoughts or ask a question. For best results please provide relevant details like your vehicle's year, make, model, engine size, the problem and when it occurs etc. - Comments need to be approved before they are seen by everyone. Notice we don't post Spam. Comment below (*SPAM, ALL CAPS & unrelated comments will be deleted). Click the following to view Dennis' "about page" for info on his background in automotive repair.

Please note: Your comment will not be posted until it's approved. We appreciate and read all on topic, relevant comments. Please don't ask for repair manual info like torque specs, wiring diagrams and specific repair procedures. If quick assistance is needed with purchasing a tool or part, please visit our tool website or call to place an order at 800-524-9783. *Note we don't offer repair advice on the phone.