Exhaust Stud Heli Coil Pulled Out, Wou is me, Help! Correction Time Sert came out Options

[913B]

ok, so I checked it again, appears the depth of hole is deep enough for the following ez lok. I think I will go with the standard external threads thinking easier to get the drill bit. I put the 27/64 drill bit in my hole and it looks like it barely have enough meat for it to clean up, but it will not go in the hole without drilling. Is this a good indicator I have enough meat for the ez lok ?

The next important part is drilling/tapping straight. I know it is VERY important, can I rent or borrow anyones jig or fixture they have made. I promise not to damage or will pay you for it. If the tap is crooked, am I all lost, is it still possible to tap the stud straight with mallet or something. Of course I am going to eye ball the best as possible. Any reccomendations and experiences to share ?

Once I buy a good quality 27/64 bit from Home Depot or whatever, I'm kinda scared of the HF one. HSS is good right no need for cobalt I think. I am going to turned it down in my friends shop so I can chuck it in my 3/8 drill and not have to man a heavy 1/2" drill under the car.

Anyone, anyone I can or borrow your jig/fixture to drill straight ?

http://www.ezlok.com/InsertsMetal/SSthreads-uncExternal.html
P/N 653-8
Internal thread M8-1.25
External thread 1/2-13
Length .484
Tap Drill 27/64
Tap size 1/2-13
Min Depth 9/16

Thanks All !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[913B]

Hmm who sells the normal M8-1.25 exhaust stud ?

[iamchappy]

Both myself and Phoenix914 have used the EZLOC with success, i used the M8 1.25 x 1/2" 13 also, I have step studs and helicoils but the EZLOC looked like the beefiest solution that i doubt would ever pull out. I have had many failures with Helicoils pulling out. EZLOC's are easily removed which i liked over the Timecerts but can be also be locked in place.

I used a hand drill on mine very carefully and wrapped tape around the drill bit to set the depth. The existing hole was my guide.

Ace Hardware or Hardware Hanks sells metric exhaust studs.

[Cap'n Krusty]

Both myself and Phoenix914 have used the EZLOC with success, i used the M8 1.25 x 1/2" 13 also, I have step studs and helicoils but the EZLOC looked like the beefiest solution that i doubt would ever pull out. I have had many failures with Helicoils pulling out. EZLOC's are easily removed which i liked over the Timecerts but can be also be locked in place.

I used a hand drill on mine very carefully and wrapped tape around the drill bit to set the depth. The existing hole was my guide.

Ace Hardware or Hardware Hanks sells metric exhaust studs.

I doubt hardware store grade studs meet the requirements. Porsche dealers can get the correct studs for you.

The Cap'n

[913B]

I found this at http://www.mcmaster.com/#

93275A030

Seems to have the right dimensions.

[913B]

Both myself and Phoenix914 have used the EZLOC with success, i used the M8 1.25 x 1/2" 13 also, I have step studs and helicoils but the EZLOC looked like the beefiest solution that i doubt would ever pull out. I have had many failures with Helicoils pulling out. EZLOC's are easily removed which i liked over the Timecerts but can be also be locked in place.

I used a hand drill on mine very carefully and wrapped tape around the drill bit to set the depth. The existing hole was my guide.

Ace Hardware or Hardware Hanks sells metric exhaust studs.

Hello, did you buy the special tool or just used a big flat screwdriver ?

[iamchappy]

Big flat screw driver. Used a punch to lock the Ezloc after installation as described in the instructions.

Ace hardware does carry good grade exhaust fasteners in the specialty drawers. Step studs and all.

Remember to oil the tap and run it in and back it out removing the debris until you reach the final depth.

[rjames]

I used a hand drill on mine very carefully and wrapped tape around the drill bit to set the depth. The existing hole was my guide.

If you go slow, it should be fairly easy to drill stratight since you already have the existing hole as a guide.

It's a scary job, but one that I found to be very easy when I took my time.

[Jake Raby]

This repair with the engine together requires surgical precision. It also requires a lot of luck.

[Cap'n Krusty]

I think more luck than precision ......................Repairing stud holes under a 911 using a drill guide is difficult enough. Doing the same on a 914, especially with a hogged out hole for a guide, is much harder, especially as the holes are at an angle to the rest of the head.

The Cap'n

[Woody]

I've done this same repair on my car and its been holding fine. I made do with what I had handy. I used an M10 time cert and then an M8 into the M10. I don't use studs, I use 993 pressure plate bolts with the tri-square head. It really helps if you have the car up on a lift so you are not working on your back. Go slow with the drill and match the other stud for the angle. Don't drill too deep. I also always use red locktite with to install time certs. Good luck. In my case, if it pulls out then I'll remove the head and have it welded but its been working great. Use a torque wrench.

[Phoenix-MN]

Both myself and Phoenix914 have used the EZLOC with success, i used the M8 1.25 x 1/2" 13 also, I have step studs and helicoils but the EZLOC looked like the beefiest solution that i doubt would ever pull out. I have had many failures with Helicoils pulling out. EZLOC's are easily removed which i liked over the Timecerts but can be also be locked in place.

I used a hand drill on mine very carefully and wrapped tape around the drill bit to set the depth. The existing hole was my guide.

Ace Hardware or Hardware Hanks sells metric exhaust studs.

Yup, this is what I used (from McMaster Carr) They make them in several body sizes for different pilot hole sizes.

[iamchappy]

Fastenal carries them also.


I had to make an extension for my tap by using a 1/4 socket and extension with a
tee handle. My regular tap handle wasn't long enough to get in there and turn.

[76-914]

I've done this same repair on my car and its been holding fine. I made do with what I had handy. I used an M10 time cert and then an M8 into the M10. I don't use studs, I use 993 pressure plate bolts with the tri-square head. It really helps if you have the car up on a lift so you are not working on your back. Go slow with the drill and match the other stud for the angle. Don't drill too deep. I also always use red locktite with to install time certs. Good luck. In my case, if it pulls out then I'll remove the head and have it welded but its been working great. Use a torque wrench.

(IMG:style_emoticons/default/agree.gif) The only thing that I would add to that is to step drill it. If you can spread it out over 3 - 4 sizes it will be a snap w/ less chance of a goof up than if you drill it all out in one step.

[Bartlett 914]

Both myself and Phoenix914 have used the EZLOC with success, i used the M8 1.25 x 1/2" 13 also, I have step studs and helicoils but the EZLOC looked like the beefiest solution that i doubt would ever pull out. I have had many failures with Helicoils pulling out. EZLOC's are easily removed which i liked over the Timecerts but can be also be locked in place.

I used a hand drill on mine very carefully and wrapped tape around the drill bit to set the depth. The existing hole was my guide.

Ace Hardware or Hardware Hanks sells metric exhaust studs.

Yup, this is what I used (from McMaster Carr) They make them in several body sizes for different pilot hole sizes.

I used these as well. You will need to grind the tap so it will thread deep enough. A bottoming tap may work. I have only plug taps so I cut mine down. These inserts may be bigger than timeserts. I have never used a timesert.

[913B]

I am 1 lucky SOB. I was successful this weekend. Thanks to the help of all your support and suggestions. What helped was slowly drilling in steps to the desired 27/64 bit for the ez lock. Yeah I can see how a hand drill would have helped. My power handdrill lickily had a speed control so I turned it way down. Oh, for the EZ lok, FYI if you want a free sample. They will send it to for free. ezlok.com They are great and I would use it again in the future.

My new question is the replacement stud I screwed in. It tightens up too far deep in the hole. When I test fit my heat exchangers there are not enough threads to screw the nut. The desired depth I can rotate the stud to by hand. So would it be ok to add some blu loctite and screw the stud to desired depth which will give me enough threads for the nut or just not use any loctite at all and just tighten it down with the HE ????????

I even thought about using a CV bolt instead. Would this ok to use or was there a very good reason why there was a stud there originally instead of a bolt.

Man I dodged another bullet this weekend.

Thanks for all the help guys.

[76-914]

(IMG:style_emoticons/default/thumb3d.gif)

[Cap'n Krusty]

I am 1 lucky SOB. I was successful this weekend. Thanks to the help of all your support and suggestions. What helped was slowly drilling in steps to the desired 27/64 bit for the ez lock. Yeah I can see how a hand drill would have helped. My power handdrill lickily had a speed control so I turned it way down. Oh, for the EZ lok, FYI if you want a free sample. They will send it to for free. ezlok.com They are great and I would use it again in the future.

My new question is the replacement stud I screwed in. It tightens up too far deep in the hole. When I test fit my heat exchangers there are not enough threads to screw the nut. The desired depth I can rotate the stud to by hand. So would it be ok to add some blu loctite and screw the stud to desired depth which will give me enough threads for the nut or just not use any loctite at all and just tighten it down with the HE ????????

I even thought about using a CV bolt instead. Would this ok to use or was there a very good reason why there was a stud there originally instead of a bolt.

Man I dodged another bullet this weekend.

Thanks for all the help guys.

One would think that the obvious answer, "use a longer stud", would have come to mind. Possibly even the "correct" stud!

The Cap'n