We’re all about clever garage hacks around here, so when we came across this ingenious thread repair tactic from the vehicle repair experts over at AGS Company Automotive Solutions, we knew it was worth investigating.
AGS got famous for its EZ-Fit brake lines, so this company knows how to take some stress out of frustrating jobs.
For starters, if you ever come across damaged threads, you should always try to use a proper tap to fix it first. If you’re not sure how, check out this 101-style article: How to Use a Tap & Die Set to Cut Internal & External Threads
But sometimes you don’t have a full blown tap and die set handy. More importantly, on some thread repairs, the damaged bolt hole is wedged deep in an engine bay or another tight spot that you can’t fit a tap into anyway.
So this trick from AGS can be really, really helpful in tough situations. And even better, it’s easy and inexpensive—potentially saving you a ton of money and hassle in the process.
Long story short, if you ever come across a bolt hole with damaged threads, the AGS folks have a clever solution that you may want to try before heading to a machine shop. Check out the walkthrough video below:
good trick ! NOW , I have a BBC block with loose head bolt threads I believe they have been compromised by rust . You can screw the head bolts in by hand, but they wobble a bit. The machine shop said he was able to torque them to 70#`s for the torque plate for boring the block . I mentioned it to him and he said just torque to 60#`s would be OK, And suggestions ??????Thanks . (it`s a 1966 396 block out to 489 )
This is a common situation on older engines. Eventually those loose threads will pull out. The easiest solution is to use a set of ARP head bolts. They use a tighter rolled thread that will overlap more with the existing holes in the block and will create a better torque capacity compared to the stock head bolts. If you don’t want to use the ARP bolts because you wnt the stock look,then the only other alternative is to but thread inserts in teh block. This is very expensive and time consuming although you may not need to do this on all the head bolt holes, but certainly to the ones across the bottom of the block since those tend to corrode the most. Torquing to a lower value wiill not allow the head gaskets to seal properly and likely you will create a coolant leak into the cylinders. I would not risk this. Think about how much you already have invested in this engine and you will see this is cheap insurance.