Newbie rebuilding SC engine
 

Hi,

I am currently in the process of rebuilding SC engine since 1 headstud broke (not splitting the block). Top end rebuild with re-ground cams.

The lower studs will be replaced with steel ones according to Wayne's bible.

Is it necessary to replace the Hexnuts with new one's? The nuts that go on the headstuds that is.

Any other "must do's" that's not covered in the book?

Thanks!

Mats from Sweden

Old hex-nuts can be reused if they are not too rusty or hex is damaged. Thread and seating surface must be clean, so torquing the nuts is not impacted by a rusty surface.

Good luck with your project. Wayne's book is a good guidance especially if it is your first build.

Hi Guenter!

Dankeschön, alles klar! schnell beantwortet:)

//Mats

Hi Trenoll and welcome to the Pelican Parts forums!

As Guenter stated, Wayne's How to Rebuild and Modify your 911 Engine Book is one of the best places to start. He also wrote a great 101 Projects for your 911 book on all the common projects you're most likely going to encounter with your car.

i have done this for your exact reason ... i replaced all the nuts as the old ones will be pretty crappy. But i disagree somewhat with one of the statements above. the threads should be clean yes, but then liberally coated with ant seize. this allows better clamping force for the required torque. i did not do this and had to retorque by head studs due to oil leaks. It even tells you in the torque section of waynes book to liberally coat studs with anti seize.

since i redid the torque all has been great

also i learned the hard way .. have your oil cooler checked for leaks. i did not , and sure enough it had a small leak. Removing the oil cooler on an SC 3.0 with the aluminum hose pretty well requires a complete drop again.

Also while its out there is a spot behind the cooler in the case that weeps oil . make sure to address this while the cooler is out.

Thanks for clarification. With "clean" I meant free of corrosion, but of course you should apply lube before torquing (pic 5-5-3 in Wayne's book) :)

Thank you all for contributions! I have Both Waynes books beneath my pillow.

Another question: would you change camchains on 120000 Km’s?

Yes, I have the hydraulic tensioners installed.

All the best

Mats

If no obvious wear or damage to chains and sprockets, chains will most probably be good for another 100 K. On the other hand they are not that expensive and you might sleep better if you just install a new set.

do not change camchain and sprockets after such low mileage is my advice. I did, for no good reason, and on last inspection it appears the new parts may not be the same quality. Some indications of wear on the cam sprockets. I suggest you be cautious and continue with original chains and sprockets

+1 better to restore every possible original German part than use Chinese crap. Nuts and bolts et can easily and cheaply be restored.