Here is another SAVE YOUR A$$ tool. Stripped out threads in thicker metal that require a stronger fastening force can look at the Time-Sert (Timesert) inserts and tool sets These serve a similar purpose as the Nutsert inserts but work a bit differently. For one thing they are much stronger and can be used in places such as Spark Plugs, Head Bolts and in my case Bellhousing bolts. These inserts more closely resemble a Helicoil but instead of being a spring of coiled wire they are a solid insert. Each kit has a special drill bit, special counter bore, special tap and a special Time-Sert installation tool. Each kit of tools is specific for a size of thread. And they are available in both Inch and Metric size as well as a bunch of special versions for Spark Plug and other repairs. The last kit of mention is the 'BIG-SERT' kit. This is for a last ditch repair when the hole may have been threaded more then once and a regular Time-Sert will be too small to be use. Click Time-Sert for their website which list all the kits and parts. I found mine on Amazon.
Big-Sert Tool Kit is Bigger then the Time-Sert Kit
This is the Big-Sert kit I used for some repairs of the Tilton Magnesium bell housing that was used on The Ripper. Each kit comes with the specialized tools for a singe insert size. The Drill bit, counter bore, tap and Time-sert installation tool make up the kit. The Big-Sert kit is similar to the regular Time-Sert kit except it uses a LARGER insert for repairing LARGER mistakes!
Time-Sert Cut Away
Here is a cut away view of the Time-Sert. Note that it's has a small flange on top. This is where the counter bore comes in to play, and can sit flush to the surface of the repair. This is not true for Nutserts or Rivnuts. Helicoils do not have this problem, but they are not as strong as the Time-Sert.
Close Up of the Time-Sert
The Time-Sert or Big-Sert is a really simple and ingenious device. Basically it's a cylinder threaded on the inside and on the outside with a small indentation that locks it in. The special tool does this. Inserts are available in many finishes, sizes and lengths.
Helicoil vs. Time-Sert
The helicoil is another ingenious save your a$$ tool, and can be used in many places the Time-Sert can. However the Time-Sert is a much stronger and permanent fix due to the construction of the insert vs. The coil of wire approach the Helicoil uses. The Helicoil is a bit easier to install but for high strength repairs I prefer the Time-Sert, and for the really botched jobs the BIG-Sert
Each Time-Sert or Big-Sert kit comes with 4 tools in a specific size for your bolt size and thread. The First is the Drill Bit, then the Counter bore, next the Time-Sert Tap, and finally the Time-Sert tool that is used to tighten down the insert into the new hole locking it into place. The finished result is a perfectly flush high strength repair.
Using the Big-Sert Kit to Repair the Bellhousing
Below are the steps required to use the Big-Sert. The Tilton Magnesium Bellhousing was picked up on Ebay from old an old Nascar parts dealer and it ended up have a couple of thread stripped out due wear and tear. The bellhousing already had a similar pressed in insert but that became loose. These bolts hold on the starter mounting plate and needed to be strong. Given the Swiss cheese nature of the metal in the holes they needed a Larger insert, and fortunately the BIG-Sert kit did the trick. Lesson here is learn how to 'Time-Sert' and anything you get from Ebay that is a Nascar pull is likely to have something wrong or odd about it.
Drill out the holes in the Bellhousing
You can see a few of the arrows on the bellhousing. I knocked out the old inserts and have the Time-Sert drill ready to do it's job. I ended up replacing all 4 of the inserts just to be safe. Also note that some of the holes were not clear behind them so a shorter Time-Sert was used where a length issue came up.
Center it up and Drill, nothing special going on here.
To make the Time-Sert flush you need to use the supplied counter bore to, well, counter bore the hole.
After Counter Bore
You can see a slight counter bore in the correct size and shape for the insert.
You can see on of the Big-Serts inserted into the bellhousing next to the one that is standing next to it. The Tap tool on the right has the Time-sert installation bit, installing the insert. I did add some RED LOCTITE on the outer threads to make sure these stay put.
Tapping the Insert Hole
After drilling and the counter bore procedures have been completed you just need to tap out the hole. Use a bit of tapping juice to keep the theads clean.