Advice Needed - Stripped Threads

36 posts · joined Jul 2007 · 29 Jun 2009, 8:48 am

#721248

I could do with some advice... one of the cylinder head studs in my 1600 stripped its threads in the engine block.

Its the old style 10mm stud.

How do I go about reparing it? I have a tap and die set - but I've never used it and am a little hessitant to tap into my block until I fully understand all the ways I can avoid messing it up further!

Would it be a case of tapping a larger thread and using a stud insert? If so, what is the recommended outer diameter? Also would it be ok to put in an 8mm stud (I have spares from an old engine)? I guess there may be issues with uneven lenthening of mixed diameter studs?

I'd love to get all the studs replaced with case savers, but am running low on money, and at this stage all I really want is to get my engine back in the car!

If I can get the funds together to pay a professional to do the job, does anyone know of someone who might be willing to travel to my place to do the job (north brisbane)as I have no means of tansporting my engine.

Thanks.

matberry Moderator Go hard or go home

8,114 posts · joined Mar 2006 · 29 Jun 2009, 9:44 am

#721254

Give me a call and I will step thru the options

Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE

VWCOOL 23 Windows of Awesome

5,158 posts · joined Jun 2003 · 29 Jun 2009, 10:35 am

#721258

Is the engine disassembled?

Pay your debts, CxxT

brisbanefastback Casual Dubber

36 posts · joined Jul 2007 · 29 Jun 2009, 3:23 pm

#721295

engine is still complete, but out of the car.

Are Helicoils or time-sert kits appropriate for this kind of job?

Brian Officially Full-On Dubber

263 posts · joined Jun 2007 · 29 Jun 2009, 4:13 pm

#721305

buy another case

VWCOOL 23 Windows of Awesome

5,158 posts · joined Jun 2003 · 29 Jun 2009, 9:30 pm

#721391

if you just want to suck the remaining life from this engine, from some VW shops you can buy a stud with a horrible oversize screw thread that digs into the 'stripped' threads in the case and allows you to apply headtorque again. But it's the last time you will use the case...

Pay your debts, CxxT

pod i`ve got to finish this thing one day

4,980 posts · joined Dec 2003 · 29 Jun 2009, 9:39 pm

#721393

brisbanefastback wrote:engine is still complete, but out of the car.

Are Helicoils or time-sert kits appropriate for this kind of job?

Ditto to this question???

meetings 1st sunday of the month
check wbsite for location
All Welcome
http://www.flatfour.org/
and on Facebook https://www.facebook.com/FlatFour

cb john Wolfsburg Wizard

470 posts · joined Jun 2007 · 29 Jun 2009, 10:04 pm

#721396

VWCOOL wrote:if you just want to suck the remaining life from this engine, from some VW shops you can buy a stud with a horrible oversize screw thread that digs into the 'stripped' threads in the case and allows you to apply headtorque again. But it's the last time you will use the case...

It is a repair stud, and it is self tapping...after use the case is still OK to be repaired with the case saver...
..at least that's what I was told...actually I'm running the engine with one repair stud...so far no problems...

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 29 Jun 2009, 11:47 pm

#721412

brisbanefastback wrote:I could do with some advice... one of the cylinder head studs in my 1600 stripped its threads in the engine block.

Its the old style 10mm stud.

How do I go about reparing it? I have a tap and die set - but I've never used it and am a little hessitant to tap into my block until I fully understand all the ways I can avoid messing it up further!

Would it be a case of tapping a larger thread and using a stud insert? If so, what is the recommended outer diameter? Also would it be ok to put in an 8mm stud (I have spares from an old engine)? I guess there may be issues with uneven lenthening of mixed diameter studs?

I'd love to get all the studs replaced with case savers, but am running low on money, and at this stage all I really want is to get my engine back in the car!

If I can get the funds together to pay a professional to do the job, does anyone know of someone who might be willing to travel to my place to do the job (north brisbane)as I have no means of tansporting my engine.

Thanks.

Case savers - helicoils - just replace the one thats damaged

that will keep you going... and not damage your case..

LEE

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

Thinker Seriously Crusin Dubber

162 posts · joined Oct 2008 · 30 Jun 2009, 12:20 am

#721417

helicoils are the way to go it will be stronger that it was to start with but it costs a little for a kit. all the instruction come in the kits and it will tell you what size to drill.
when i say stronger that is if you do everything by the instruction and you drill a perfect hole.

1970 bug /1500 stock as a rock.
1976 standard bug ready to be modified 😁😁😁😁😁

pod i`ve got to finish this thing one day

4,980 posts · joined Dec 2003 · 30 Jun 2009, 12:22 am

#721418

cool i'll borrow the kit from work,as they supplied the helicoils as well👍

meetings 1st sunday of the month
check wbsite for location
All Welcome
http://www.flatfour.org/
and on Facebook https://www.facebook.com/FlatFour

Thinker Seriously Crusin Dubber

162 posts · joined Oct 2008 · 30 Jun 2009, 12:28 am

#721419

they are dead easy to use just make sure you follow the instruction or it can get messy and when you tap into aluminium use kero it stops any thread tearing.

1970 bug /1500 stock as a rock.
1976 standard bug ready to be modified 😁😁😁😁😁

pod i`ve got to finish this thing one day

4,980 posts · joined Dec 2003 · 30 Jun 2009, 12:48 am

#721420

i'm a fitter by trade but good advice for everybody else👍

meetings 1st sunday of the month
check wbsite for location
All Welcome
http://www.flatfour.org/
and on Facebook https://www.facebook.com/FlatFour

ctefeh Wolfsburg Wizard

479 posts · joined Apr 2005 · 30 Jun 2009, 3:10 pm

#721483

Paul,
Funny this came up as I was reading this a few days ago :

http://www.shoptalkforums.com/viewtopic.php?t=125566&start=0

Soild insert vs Helicoil....

Whaddayareckon? Belabouring the point and it doesn't matter too much what system you use or "best practice" for mag?

Regards
Sean

pod i`ve got to finish this thing one day

4,980 posts · joined Dec 2003 · 30 Jun 2009, 4:04 pm

#721491

Sean, after reading that, helicoils look to me to be virtually worthless in aluminium,so case savers look to be the go👍

meetings 1st sunday of the month
check wbsite for location
All Welcome
http://www.flatfour.org/
and on Facebook https://www.facebook.com/FlatFour

eraser Fahrvergnugen

970 posts · joined Mar 2005 · 30 Jun 2009, 4:57 pm

#721497

mm case savers and while your putting one in just try and check the tightness of the other studs.

1500S Custom Title Time!

1,418 posts · joined Mar 2005 · 30 Jun 2009, 6:47 pm

#721512

ctefeh wrote:Paul,
Funny this came up as I was reading this a few days ago :

http://www.shoptalkforums.com/viewtopic.php?t=125566&start=0

Soild insert vs Helicoil....

Whaddayareckon? Belabouring the point and it doesn't matter too much what system you use or "best practice" for mag?

Regards
Sean

After reading some of the posts on this ilnk it makes you realise how misinformed some of the Merkins are!

The original mag alloy case machines ok without lubricant but softer aluminium requires a lubricant to prevent the metal from sticking to the cutting tools. Kero is ok but Tapmagic for aluminium is a purpose made lubricant.

As for the use of Heli-coils, ask Stan the Man what he uses in his rebuilds before installing the head studs.

Some of the Dubbers on here may have attended TAFE as an apprentice Fitter and Machinist where they did tests using Heli-coils. In the test with the M8 hole tapped directly in the aluminium bar, the set screw was torqued untill the thread stripped and noted. The hole was then Heli-coil inserted and the test repeated. The result was that the torque was increased without stripping untill the head sheared. Now who says inserts of the "spring" type aren't suitable!

Just my 2 cents worth.

If anyone west of Sydney wants a case drilled for inserts, give me a yell and by the way, yes it will be machine drilled and tapped!

DH

pod i`ve got to finish this thing one day

4,980 posts · joined Dec 2003 · 30 Jun 2009, 7:08 pm

#721518

1500S wrote:After reading some of the posts on shoptalkforums, it makes you realise that many Merkins haven't a clue when it comes to engineering!

The original mag alloy cases do machine ok without lubricant but kero and the Tapmagic (for aluminium) etc doesn't hurt. Softer aluminium definitely needs lubricant to stop the metal sticking to the cutting tool.

With regard to Heli-coil and similar repair inserts not being suitable, ask Stan the man what he used for many years (and maybe even now) as standard for all the head studs in his rebuilds.

According to Heli-coil, the use of the inserts in aluminium results in a stronger thread than just a tapped hole. Maybe there are some Dubbers here who have gone through the TAFE system as an apprentice Fitter and Machinist where Heli-coil provided test pieces of aluminium where the torque was increased untill it stripped the aluminium thread. The test was repeated and the result was the sheared head of the bolt. So who says that the Heli-coil "spring" type insert isn't strong enough.

Just 2 cents worth of something to think about!

AND, if there's anyone out west of Sydney who needs cases drilled for inserts, give me a yell.

point taken 1500S,might start with heli-coils as i have them already then if and when anything happens to them it wouldn't be hard to make and upgrade to a solid insert ,but this is all good discussion to the pros and cons of the 2 different systems👍

meetings 1st sunday of the month
check wbsite for location
All Welcome
http://www.flatfour.org/
and on Facebook https://www.facebook.com/FlatFour