Porsche Enthusiasts Club Forum

I thought are simply take the can cover off 2 inpected the cam chain and can shafts. How ever on removal one off the bolts snapped, it wasn't 2 bad as some was still remain so I managed 2 remove the bolt, but! When I was reinstooling the rocker/cam cover another bolt snapped, but this time it's in side the engine block, it the top left corner under the fule lines. Is a tap and die set the only and best option 2 remove?

Also is it Likely 2 be harmfull 2 still use the car? Every other bolt has tightened up well. ? Iv ran the engine and drove it 4 a few mins and can't see any oil come from around the missing bolt

You could try using these,

http://www.screwfix.com/prods/20084/Van-Car-Accessories/Mechanics-Tools/Stud-Extractor-Set-8-Pc

You drill a hole in the middle of the snapped stud and these are a left hand thread, so when you screw it in it gets tight and rewinds the snapped stud out. I use them alot, as I'm a bit heavy handed. Dangers of working on steam boilers, then on smaller stuff.

Let us know how you get on.

Thanks,


My dad tryed drilling it but it hasn't snapped squre. It's at an angle.

Just thought I should add that the bolt snapped below inside the tread of the engine head. Don't think the stud extractour would work. Anyone recommend a good tap and die?

Build it up with weld and it will simply screw out. The weld doesn't attach to the aluminium only the steel!
Alasdair

Thanks, what should I weld 2 it? Something I can get a spanner on? Or just lump it up and try and get some grips on it? Will heat from the weld cause and harm 2 the engine? Should I use copper rods?


Did you get my email about them seats ?

Hi Terry, just build it up with weld and use some grips to get it out. Seats are sold unfortunately! Use a mig as rods would be a pain to get into!
Alasdair

thanks, iv got a mig welder were it feeds the rod though. but what wire sould i use?

just give the car to a professional before you wreck the head completly. Weigh the cost of a good engineer against the cost of a garage fitting a new cylinder head

I would strongly recommend that you do not use a stud extractor. i have never seen one work sucessfully.

Even If you manage to drill the stud squarely and turn the extractor into the stud if you then shear the extractor you are totallly screwed. The extractor is hardened steel and cannot be drilled .

You need to set up a drill ,screwed to the head preferably,and drill the stud centre with a very tiny drill bit something like 1/16" .

Use the drill on its very slowest setting about 1 or 2x rpm per second maximum .

Then use a 1.8" and so on until the stud is drilled out and you can fit a Helicoil

The mistake that most people make when drilling steel is to drill too fast so that either the bit simply skids off or it gets red hot and blunts

I have used a stud extractor sucessfully on cars, boilers, compressors, pumps and air conditioning units. If they didn't work then they would not sell them. However if the stud is so tightly in, then yes it could snap the tool. I don't think it was that tight as it was only being put back in after sucessfully being removed. Like you say, if 2 bolts have sheared already, maybe cheaper to get a professional to do it than pay for a new head.

frankly lee without meaning to be rude, the OP's competancy of spannering doesn't exactly inspire confidence. You and I both know that extractors can be effective but they require a high level of competancy, sensitivity and experience to be effective. They would not be my first choice for an in-experienced DIY'er

Unless the studs/bolts were fairly new they should have been replaced as a matter of course. They are soft because they are used in aluminium and should be removed and installed slowly so that heat doesn't expand the metals and jam the stud .If they were a tight fit I would have cleaned the threads first with a tap.

Tack welding to a stud is another sucessful method which requires a deft touch and experience . As this stud has sheared below the level of the deck I would suggest that drilling and tapping is likely to be the easiest ,least damaging route but it must be drilled very very slowly and using a new ,very small pilot drill to get a centred start.

This is why I would recommend an Engineer rather that a mechanic.