[Blasirl]

Is it plastic or metal that is stripped? If metal, put in a Helicoil. If plastic, you could try adding plastic to the opening via a plastic welder or soldering iron. Try and determine what type of plastic it is. Most of the time you can use cut off Ty-wrap ends as it is a universal type plastic. Then re-tap it.

Polyvance

Plastic Welding Tools

Modern Plastics

Cheap plastic welder

 

[veronduh]

Thanks for the reply!
It's the metal bolt that's stripped. Would using a helicoil require drilling into the cylinder head bolt hole? That would make me nervous!

 

[snowwy66]

You'll have to drill in to the hole if you can't by any means get the broken bolt out.

Once drilled you'll have to make new threads. I would just use a tap, rethread the hole and use a bigger bolt. Cheaper then accomadating and buying a helicoil. To which you'll still have to buy a new bolt. But if you want to use the same size bolt. Then helicoil it.

Put a rag inside the top of the head to catch any metal shavings that might fall that way.

 

[MP81]

But seriously, do not do that.

 

[turbo96]

Sorry!

 

[Jondaytona]

Typically a steel bolt will pull aluminum threads, not the other way around. Maybe you're seeing the aluminum threads stuck on the end of the metal bolt to where you can just thread them off by hand?

If you're talking about the steel bolt that screws into the aluminum head/threads, then a thread repair kit like Helicoil would be best. As far as drilling, use the previously suggested method of covering things up with rags or something similar, then use a shop-vac after drilling, then remove the rags. Also, a thread repair kit is designed to replace existing threads without having to drill too big like if you were going to the next bolt size. Furthermore, drilling an existing hole is not a big deal because the Helicoil bit will only take out the threads and bottom out, then you'll feel it stop. You'd have to push a lot harder to keep it going before doing potential damage to the head. Just keep the drill straight.

No offense, but if that scares you, then you should just take it to a reputable shop and have them do it.

 

[Taxman]

Sometimes these things can work miracles.

Use the die to clean up the screw if you can't find a way to remove and replace it (go a fraction of a turn at a time then back up), use the tap to clean out the hole.

https://store.snapon.com/Rethreading-Taps-and-Dies-C629453.aspx

 

[alexhatcher]

since you're going to be drilling into the head, get tape and HeavyDuty plastic and basically prevent any metal filings from getting into the valve body.



get quality metal drill bits. (not harbor freight) and drill into the center of the broken stud. THEN extract it with a extractor.

https://www.youtube.com/watch?v=K34RS6M11uw

 

[veronduh]

Thanks for all the advice everyone! I'm going to take it to a local, trusted shop and have them do a heli coil repair. I'm not confident that I won't screw it up even worse. I'll update later on how much it costs at shop price in case anyone in the future needs this repair as well.

 

[totrox]

Aluminum Block Thread Repair

After replacing my valve cover because of a worn out PVC, I had one bolt that wouldn't tighten. Oil was spilling out. I Used a product called OEM Fix-A-Thred purchased from local Pep Boys to repair my threads on one of my head holes that was stripped on the aluminum head my 2012 Cruze 1.4 LTZ.
The size needed was M6 - 1 (Part Number 25626). After removing the aluminum stuck to the groves of the threads of the steel bolt I know what had to happen. The system did not come with a 1/4 bit to remove the old damaged stripped threads but every think else was included. After watching a short video on youtube - produced by the system makers I found the process worked well and completely. I was relieved that the bolt held firm and I was back in business. Just make sure to watch the good video and understand it completely before you start repairing the threads. Go slow.