: Northstar head gaskets replaced -- a good thing?

06-29-07, 12:36 AM
I bought a '97 Seville STS with ~85K a little under two years ago. Now I'm at 100K, and I'm wondering about the odds of the engine holding on for an additional 50K, maybe even another 100K. (If the engine has a good chance of holding on, I might drop some money into changing the transmission fluid and some other things too).

The head gaskets were replaced by a Cadi dealership at 75K (along with plugs and wires). Do these replacements -- assuming they were performed properly -- improve the odds of the engine lasting for another 50-100K? Or do they lessen the odds of survival, or have no effect?

Hope to hear back from someone.

06-29-07, 09:30 AM
If the block was repaired using Timeserts, the engine should be bulletproof, almost forever. It's generally been shown that a properly Timesert'd engine is stronger than stock, and a lasting repair is "almost guaranteed". Of course, nothing is truly guaranteed, but assuming the repair was done using Timeserts (and this is not always the case), you should be good to go for a LONG time.

If they were not done properly (the head gaskets), you may have issues again soon. Just as a properly repaired engine has proven to be VERY durable, an improperly repaired engine has proven to fail again in short order (within 10-20k miles perhaps). I would try to get the repair record for that repair and see what parts were used. If you can know positively that Timeserts were not used, frankly, I wouldn't hold out much hope for a long service life. The engine can be repaired again (using either Timeserts or Bigserts {which are larger Timeserts}), but it would obviously be a costly repair.

06-29-07, 02:27 PM

OK I called the dealer who did the head gaskets.

I was going off memory and I asked if a "thread-lock" chemical was used during the procedure (wrong thing to ask).

The response was that the threads were re-done and that new, different bolts were used, and that "thread-lock" was not used, because there's already something on the new bolts. The person went on to say that when the head-gaskets were replaced they were "done differently from what existed originally", and there is almost no chance of them failing again.

Does the above seem like a description of "timeserting"? I suppose I could call again and ask the right question this time, but that would be a little embarrassing for me. Is re-threading and using different bolts the “timesert” procedure?

06-29-07, 04:59 PM
Yes, it sounds exactly like Timeserting. Timeserting is rethreading and inserting a threaded insert. New, thread lock coated bolts are used. Sounds like they did the job right. Check out http://www.timesert.com. Once you see the insert, you'll better understand it.

06-29-07, 08:59 PM
^^^ OK thanks for the info. I looked at the website.

It sounds like the head gaskets were probably "done right". So I guess I lucked out there.