2.7 questions - timeserts, and studs

[rjg]

Hi,
I'm new to the board, and I have a couple questions. I'm asking because I'm thinking of buying a mid-year 911.

What is involved in installing timeserts on a 2.7? Is this only practical when doing a full rebuild? Do the pistons and jugs have to come off, or can you drop the motor and remove the heads?

Is there a different type stud that should be used on a 2.7 (without timeserts), or is it a matter of just waiting until they pull?

TIA

[J Richard]

Hey there RJG welcome to the board!

You may want to look at the 2.7 engine thread prior to your purchase. The studs that pull are the ones that thread into the case and hold the heads and jugs onto the case. Once they start to pull you will get a compression leak which left unchecked will cause damage to the sealing surface of the head and jug. The problem is they pull the threads out of the crankcase, so the jugs and pistons must come off to machine the holes for time serts. In addition sometimes the insertion of the time sert can cause distortion in the side of the cylinder spigot which must be relieved to fit the cylinder back into place. It is also important that the inserts are put in straight or you can't get the head back on. While some people do this by hand the best way is to have it done by a shop on a jig. This means taking the motor all the way down. Thats why this is such a problem.

If the threads are ok you could use Dilivar studs (that have the same expansion coefficient as the jugs) or the raceware $tud$.
Most likely the threads will have some damage just removing the stock studs.

Its a crapshoot if you have the problem or not, these are good motors if they are fixed right. But getting one with this problem is a real downer. (yea, I had one... ) After it was fixed it was a great car. If you are looking at one check to see if work was done or if it has evidence of a problem. And get a PPI!!!!

Hope this helps.

[RoninLB]

There are plenty of 2.7 911 out there with every upgrade and great machine work on a rebuild. They are relatively cheap. Find one from some one that is serious about his 911. They are old enough that if they are in good shape it probably has been done already. You want to see history on paper. Rebuilding costs big bucks.

[Wayne 962]

Agreed, full rebuild to replace the studs...
(to do it right)
-Wayne