: Northstar headgasket -- want to get 'er fixed, looking for words of wisdom



wachuku
11-11-10, 04:41 PM
'97 Seville STS, just turned over 150K.

Was loosing a small amount of coolant over the last few months (~ two pints every 2-4 weeks). Worried about it and looking for leak but couldn't pinpoint anything. There did not appear to be other potential headgasket symptoms such as coolant in exhaust or engine-temp spikes, etc. But then a few days ago the engine overheated on way to work (And just prior to that fateful trip there was pressure in what was a warm, but not hot, coolant reservoir). Pulled over immediately and towed Cadi to mechanic after work. Mechanic says he confirmed headgasket leak by coolant pressure check.

Other than the headgasket I think the automobile is in pretty good shape. With the help of this forum I have fixed several issues and replaced several parts over the last three years -- rear shocks, air-leveling compressor, fuel pressure regulator, fuel pump, steering wheel position sensor, A/C compressor and related components, transmission fluid drain and replenish (and of course coolant drain / replenish too), wood steering wheel, front/rear sway bar links and bushings -- just to name a "few" things off the top of my head.

A mechanic who formerly worked at GM and who is familiar with Cadi's looked the car over and said it looks good -- CV, suspension, brakes, and so on -- so I'm presently on the path of repairing the headgasket issue.

I'm in MN so I'm I thinking of bringing the car to northstarperformance (www.northstarperformance.com) in Manitoba.

Does anybody have experience with, or know anything about, northstarperformance for headgaskets?

Also, are there other things to get done if I do follow through with northstarperformance? Apparently they seal the oil pan gasket (yes mine leaks, not a huge big deal though), but anything else?

There's been a "ticking" that I've always wondered about -- I tried to time it out and it seemed to be at half RPM so I'm suspicious of lifter (or maybe cam?) issues -- although I've heard it could just be a lax timing chain tensioner. Would headgasket repair be a good time to fix lifers? And if the exhaust cams are worn and causing problems -- I've heard they wear on years such as '97 -- can they be replaced easily and not at a great cost?

Any other major things to be aware of?

Submariner409
11-11-10, 05:38 PM
Take it to Jake (Northstar Performance) or one of his satellite/approved shops. They will do what you specify: a top overhaul with studs or a complete engine re-seal. Depends how much you like the car and how deep your pockets are: either way there's a LOT of labor.

Cams and lifters are literally worth their weight in gold - pray.

If/when my gasket(s) go the engine goes to Jake.

jimsbox
11-12-10, 05:26 AM
I am confused, I thought overhead cam engines do not have lifters because there is no need for pushrods. My understanding is the rocker arms operate directly on the cam lobes. Am I mistaken (wouldn't be the first time and probably not the last either!)?

Submariner409
11-12-10, 10:20 AM
I am confused, I thought overhead cam engines do not have lifters because there is no need for pushrods. My understanding is the rocker arms operate directly on the cam lobes. Am I mistaken (wouldn't be the first time and probably not the last either!)?

Common transposition of parts names - technically an OHC engine has "cam followers" which are either flat-tappet style or roller. The term "lifter" is used interchangeably in service manuals and forums - old habits die hard.

The pre-2000 engine cam lobes (wachuku's engine) act directly on the "bucket" hydraulic cam follower which covers the valve stem top and retainer. The 2000+ is a roller follower with a static hydraulic lash adjuster as pictured. (If allowed, this engine will go to 8,000 rpm no sweat.)

jimsbox
11-13-10, 04:08 AM
Thanks for the info, I am showing my age. I was thinking back to my MGB with solid lifters that had to be adjusted to .015 every 12 to 15 thousand miles or it would sound like the engine was a popcorn maker. Most unreliable car I ever owned but boy what a blast to drive on a mountain road!

Submariner409
11-13-10, 10:08 AM
Thanks for the info, I am showing my age. I was thinking back to my MGB with solid lifters that had to be adjusted to .015 every 12 to 15 thousand miles or it would sound like the engine was a popcorn maker. Most unreliable car I ever owned but boy what a blast to drive on a mountain road!

You had it easy - try a 1953 MG-TD for maintenance (an engine a year) !! (or my 1957 Jag XK140-MC)