shmucklebuckle

3 holes for the studs in my block have stripped threads. I bought a Time-Sert kit for making the repair, but the threads are so deep in the block that I don't know how I can get to them with the drill bit, tap, and installation tool to fix them. Am I screwed? From what I've gathered, heli-coil instalation presents the same issues, so that wouldn't work either.

Got any ideas? I've been racking my brain about this for days now... is my only option to replace the block? Thanks guys.

Tom M'Guinn

I've not done it myself, but know plenty of people have timeserts for their head studs. Some even use custom over-sized studs. I would't try it at home -- find a good machine shop for this. Ollie's is in s.cal --they could do it...

mjensen

Which threads are in need of repair? My head was rebuilt by LR and they installed 3 heli-coils for the header, so far - ok.

Zero10

It can be done, but the tools for the deep ones are more expensive.
They have longer drill bits, extended taps, etc., but they're so pricey that only machine shops ever buy them.
You will probably have to take it in. On the up side, if you have the time-serts already, they might charge you less?

Tom M'Guinn

I assumed he meant head studs, since those are the only deep-set stud holes in the block itself. Helicoils work great in the head/cam-tower/intake. I have more than my share in my car. I guess I tend to over-tighten things.

Jim @ EuroWerks

I've repaired a few blocks with stripped head stud holes and drilled out a few broken studs . I'll give my 2 cents if needed . Headstuds ? The tools are not stupid expensive it's just time consuming .

shmucklebuckle

Ok, so extended taps and time-sert installation tools exist. I will ask at the place where I got my time-sert kit, but does anyone else know where I might find those for 12x1.5 threads? Jim? It's still cheaper for me to buy the two extra tools than pay a machine shop to do it, I'm assuming. If I have to pull the block to have someone else do it, then I may as well just get a new one. And yes, I'm dealing with head stud threads in the block, not exhaust, intake, etc.

Tom M'Guinn

You may want to call someone like Scott Gomes (area951.com) -- he is set up to do this kind of work and I assume he can give you a quote to do the work and perhaps point you in the right direction if it can be done with the block in the car. (Places like Ollie's or EBS can probably do it too, but Scott focuses on the 944.)

How did they strip -- when removing the original studs?

Jim @ EuroWerks

If it's only the threads pulled , I've had great luck with Heli-coils .The Hole is so deep , That timecerts don't seem to be the best answer . Keep in mind that when you look at the stud threads that go into the block they are quite long .I usually put in two one over the other . I was a machinist before working on P-cars . All my repairs were with engine still in car . I've never had any studs pull out even on the heavily raced PCA turbo . That was the worst one . He broke the stud in the block then got way off center while drilling . 7 years later and it's still ok .
Start with the Drill bit for the heli coil kit . Either find a socket to fit the top of the bit or cut the top of the bit for a socket to fit it . Then I put a socket on it and slowly cut into the block with a rachet and extension (1/4 inch drive ) . Always Measure !!!!!!!!!!!!! When you keep the extension centered in the hole , then the hole drilled has to be straght . Take the bit out often and blow out the debris. When tapping the hole do the samething . Socket on top keeping the extension centered .
Remember when installing the heli-coil that another is going ontop ,and the threads are the same in the hole from top to bottom . So, even if the coils are not touching it's ok . I like about 2 threads between them . Because you have to break off the tab of the coil after installation . Make sure to measure , measure , measure as you want to use as much of the thread of the stud as possible , without heli-coil sticking out the top or bottoming out . Yes I'm nervous the whole time . But I know it can be done and realiable .
Drilling out studs takes me about 8 hrs for each repair . repairing stripped holes about 45 min - 1 hr apeice . If you need anymore help let me know . If you wait till next weekend I'll be harder to get ahold of . I'll be at road atlanta .

shmucklebuckle

Wow! Great advice, thank you Jim. My studs are all still in great shape. I think the block stripped from repeated torquing. I don't have the original motor (bought the car that way), and I guess after I put in new studs the first time around, the alluminum gave up, as I imagine it would, long before the steel studs would do so. I will re-evaluate what I've got to work with, and probably hit you up with a few more questions either later today or tomorrow.

shmucklebuckle

They stripped (I'm guessing) from repeated "use." The Raceware studs are hardened steel I think, and they claim that their studs don't stretch, so if something's going to give, it would be the block first. I believe they must have been border-line effective after I finished putting the head on the first time, and after running for a few hundred, they gave and couldn't provide the needed tension. All speculation though.

Jim @ EuroWerks

We run raceware in the turbo s that are running alittle extra . The only bad thing I could think of is ... I would hate to have to drill out one of those ! I just pulled a set out of a modified engine last week and they turned out by hand . With the factory studs we usually put oil in the stud hole (with the stud ) for a couple of days before attempoting to pull them out . Makes a difference .

shmucklebuckle

I found sockets for each of the 3 tools (drill, tap, and installer) that will fit in the hole in the block. I'm not sure how I can stack two time-serts in each hole and keep them spaced so the threads will match up between the two. I'll have to cut the flange off the top of the bottom time-sert in each hole to stack them. If I can't figure out a way to make that work, do you think 1 time-sert will be able to take the 66 ft/lbs?

Jim @ EuroWerks

Trev, ck my posts . I never said time-certs . Heil coils . Big difference . how do you get them paced evenly . Measure , Measure , Measure . I've done several and none failed . I did have to make a larger time-cert for the stud that was drilled off center .

I'm sure you could use a time -cert , But use a long one and I would not stack them . I would use the heli-coil

shmucklebuckle

Jim,

Sorry for the mix up, I know you said heli-coils. It's just that I've already got the time-cert kit, and I've been intending to still use it instead of buying a heli-coil kit and having a time-sert kit for no reason.