: northstars in general



biggr101
04-06-07, 12:30 PM
hey guys,i just want to know are there any particulars to look out for when purchasing a vehicle thats nortstar equipped.i noticed alot of them either overheating or already diagnosed for headgaskets.are there any years thats better or worse than others?is there one that doesnt eventually require head gaskets?does it matter the mileage?any help appreciated cause i really want a deville and i see more with nortstars then 4.9's.

eldorado1
04-06-07, 01:44 PM
It was supposedly fixed in 2000

mileage doesn't matter... year probably doesn't matter.

Cadillacboy
04-06-07, 02:22 PM
Maintenance is a rule of thumb.
I think a car with a lower mileage but poor maintenance doesn't mean it's better to a higher mileage car with a good maintenance .

eldorado1
04-06-07, 03:34 PM
Maintenance does help, but I don't think it helps much. I'd guess 3 out of 4 head gasket problems are due to the threads pulling out of the block... Something you have no control over...

Ranger
04-06-07, 05:16 PM
Cooling system maintenance is the biggest factor (though not a guarantee on any aluminum engine). Make sure the coolant has been changed as recommended.

jadcock
04-06-07, 09:03 PM
Cooling system maintenance is probably THE most important factor. On ANY aluminum engine, you can have cooling system problems if the cooling system is not maintained. Reason being, aluminum doesn't rust away, like iron does. On an older iron engine, you know when corrosion is taking place -- the coolant starts turning a rusty red. On a newer aluminum engine, you can let the block get completely eat away (in theory), but the coolant will remain the color it started. There's no good indication to the owner that the coolant needs replacing. 5 years or 150,000 miles is the spec for the Dexcool coolant.

There were some revisions to the engine in 2000, and those revisions include slight differences in the head bolt area. I understand the thread pitch was changed, and the bolts themselves are physically longer, with more thread contact area. I'm sure this equates, to some degree, to a lessened probability of head gasket failure, but to what extent, we don't know.

It shouldn't be assumed that all Northstars are going to need head gasket work at x number of miles. My '97 has about 156,000 miles and the head gaskets are original. Lots of folks are running around with the original head gaskets in the engine. Certainly, as the engine ages, as is the case with ANY engine out there, the potential for major problems rises, but I don't think it's fair to assume that every engine out there is going to need an overhaul due to this one issue.

z06bigbird
04-07-07, 05:03 PM
hey guys,i just want to know are there any particulars to look out for when purchasing a vehicle thats nortstar equipped.i noticed alot of them either overheating or already diagnosed for headgaskets.are there any years thats better or worse than others?is there one that doesnt eventually require head gaskets?does it matter the mileage?any help appreciated cause i really want a deville and i see more with nortstars then 4.9's.

I would kill to locate a low mileage 4.9. In fact, we have a joke around my house. About 6 years ago, a friend of mine had a serious health problem. All expected him to die. He agreed to sell me his 92 SDV with 25k on it. Well, the guy is not driving although someone in family keeps the car running. I just don't understand why he doesn't die. I want that car. Just joking.

Getting back to Northstars, here is my opinion with some actual facts:

1. All Northstars have an extra fan belt ($11) on driver's side just behind radiator. That belt runs water pump and needs to be changed before it breaks. When it breaks, you are likely to cook engine. You can change it yourself--very easy.

2. The earlier Northstars (93 to 2000 or so) have a real problem when the engine overheats. The head bolts pull up and strip the holes in the block. Dealer typically is only one who has special $1500 digital tool to correct problem. Even then, repair is probably $5000 give or take a 1000.

3. Early Northstars also were known for major oil leak problem. This block is a 3 piece block. The original seals in the block did not seal well on some of them. Oil would literally POUR out of the block. Again, dealer fix only. Expensive. Engine must be pulled from bottom of car; all suspension must be removed, etc.

4. Starter on Northstar is under intake manifold. Expensive repair.

5. If you live in high heat and where there is high moisture, spark plug wires ground out--sparks jump. Wires break down. Dealer charges about $600. You can do it youself for the price of wires. Dealer charges for diagnostics, wires, installation, etc.

6. DO YOU STILL WANT A NORTHSTAR????

Now, in 2002 I bought the nicest 1997 Crimson Pearl (like candy apple red) Sedan de Ville with 21k miles on it. One owner, little old lady. Perfect car. Not a scratch on it. I loved it, but I just sold it at xmas. Never any problems. I had 5 new tires on it, new batt, hoses, belts, fuel filter, air filter, etc. I am a not on maintaining cars. In 5 years, I put only 6000 miles on it. 28 mpg too on highway. I just sold it because I was afraid that if something happened to this engine, I would be stuck with a very expensive bill on an OLD CAR. New owner bought it without even taking it for a test drive--$12,500. Blue book is probably 7k on that car, but buyer could see how I maintained that car. I do miss the car, but I will buy another much later model Caddy in the future. Right now I am driving a 2005 LeSabre with 12k miles on it. ALMOST as comfortable; good gas mileage, but not the same as a Caddy. Biggest advantage is that I have absolutely no worries about engine with this car.

Now that I have confused you....

If you find a Northstar, take a 1 hour test drive (or longer) to check the temp. Look under car for oil leaks. Take VIN to local Caddy dealer for a print out of maint history.

Ed

jadcock
04-07-07, 05:38 PM
Getting back to Northstars, here is my opinion with some actual facts...


Some facts to go along with your facts...

1) Good point -- the water pump belt is on the driver side of the engine and provides extra protection against overheating if your regular serpenting belt breaks. On normal engines, that (serpentine belt breaking) would stop the water pump. On the Northstar, the water pump is driven off the left-hand intake camshaft.

2) I'm not sure what the "$1500 digital tool" is you're talking about, unless you mean the Tech II, and a $5000 repair bill for new headgaskets is outrageous, even for dealer pricing and especially for third party pricing. You can get an entire engine for that. A common/typical repair bill for headgaskets is in the $2000-3000 range.

3) The case half gasket and oil pan gasket are not in high pressure points. Oil does not "pour" out of the engine at this location. If you have a major oil leak that produces more than a few drops overnight, look elsewhere, like an oil filter adaptor gasket or oil cooler o-ring. The "case half leak" is probably one of the most mis-diagnosed problems (aside from headgaskets).

4) The starter is one of the easiest starters you'll ever replace. You'd be robbed if you paid someone to do it. No laying on your back under the car, no hoisting the starter in the air and messing with shims. The starter is in a safe and dry place under the intake manifold, keeping it out of the salt spray and other sources of corrosion under the car, making the chances of starter failure on these engines remarkably low. If you do have to replace a starter, however, it's a very easy job. The intake manifold is dry with no coolant, making removal a snap.

5) Your point about spark plug wires breaking down is valid for any engine. The original ACDelco spark plug wires on these engines normally last for 100,000+ miles. I had to replace the original plug wires on my '97 at about 135k miles, but only because they were mishandled by the dealer during the fuel rail recall.

6) I don't see why not!

Its unfortunate that you let your paranoia drive you to selling an excellent car (your '97 DeVille). It'll likely be running years and years into the future.

Ranger
04-07-07, 08:09 PM
Well put Jadcock. Many wrong "facts" in post #7.

Submariner409
04-07-07, 10:05 PM
......and a post-'01(?) N* doesn't have any plug wires, anyway. It's COP (coil on plug) with insulated connector boots between the coil packs and double platinum AC Delco plugs, which are good for 100Kmi. (don't get anal or creative about the AC plugs. Search the spark plug threads....) If you read horror stories here regarding the N*, remember that those stories represent 1/10 of 1% of all N* engines out there........my 327 Chevelle had its share of bugs, too.......Z06, you threw away a great car.......hope you're not so antsy about aircraft engines........!

clarkz71
04-08-07, 07:40 AM
2. The earlier Northstars (93 to 2000 or so) have a real problem when the engine overheats. The head bolts pull up and strip the holes in the block. Dealer typically is only one who has special $1500 digital tool to correct problem. Even then, repair is probably $5000 give or take a 1000.

3. Early Northstars also were known for major oil leak problem. This block is a 3 piece block. The original seals in the block did not seal well on some of them. Oil would literally POUR out of the block. Again, dealer fix only. Expensive. Engine must be pulled from bottom of car; all suspension must be removed, etc.

4. Starter on Northstar is under intake manifold. Expensive repair.

5. If you live in high heat and where there is high moisture, spark plug wires ground out--sparks jump. Wires break down. Dealer charges about $600. You can do it youself for the price of wires. Dealer charges for diagnostics, wires, installation, etc.

6. DO YOU STILL WANT A NORTHSTAR????


Ed


:bsflag:

eldorado1
04-08-07, 11:05 AM
1. All Northstars have an extra fan belt ($11) on driver's side just behind radiator. That belt runs water pump and needs to be changed before it breaks. When it breaks, you are likely to cook engine. You can change it yourself--very easy.

True.



2. The earlier Northstars (93 to 2000 or so) have a real problem when the engine overheats. The head bolts pull up and strip the holes in the block. Dealer typically is only one who has special $1500 digital tool to correct problem. Even then, repair is probably $5000 give or take a 1000.

Timesert kit (I assume you're talking about) is ~$400 new. Repair is expensive, because the engine should come out. Lots of labor there.



3. Early Northstars also were known for major oil leak problem. This block is a 3 piece block. The original seals in the block did not seal well on some of them. Oil would literally POUR out of the block. Again, dealer fix only. Expensive. Engine must be pulled from bottom of car; all suspension must be removed, etc.

Maybe. I would expand that to say "all" northstars were known for "minor" oil leak problems. The oil manifold and half case seal are known problem areas. They are expensive to replace. Most people live with a couple drops of oil on the driveway. It's not a big deal. Really.



4. Starter on Northstar is under intake manifold. Expensive repair.

Only expensive if you don't know any better. It's a 1 hour job, and you don't even get dirty. (Try saying that on an SBC with headers that have to come off first, etc) It's easy to dupe customers by saying "well, the top half of your engine has to come off.... that'll be $2000." The truth is, 4 or 10 bolts are all that need to come off, then you just move the manifold out of the way and you have that starter staring you in the face.



5. If you live in high heat and where there is high moisture, spark plug wires ground out--sparks jump. Wires break down. Dealer charges about $600. You can do it youself for the price of wires. Dealer charges for diagnostics, wires, installation, etc.

So don't go to a dealer. My wires cost me $40 and have lasted me 5 years now. I got my money's worth out of them.



6. DO YOU STILL WANT A NORTHSTAR????

Even if all those problems were not blown out of proportion - YES.
:bouncy:

biggr101
04-08-07, 11:51 PM
thanks for all the replies.they've definetly given me some added insight.one more question though;what are timeserts??

I~LUV~Caddys8792
04-09-07, 01:09 AM
So what's an average headgasket job on a Northstar cost when done at a dealer anyways? $2000-3000? If one could pick up a nice late '90s N* Cadillac for I dunno....$7200, and have a HG go on them, they're in for what? Like $10,200 total at most? That's not so bad considering the car cost ~$42,000 new eight years ago.

jadcock
04-09-07, 09:28 AM
I agree that buying a used Cadillac with a known HG problem might be a good choice, if you're looking for a project car and do it yourself for about $500 in parts. For not a lot of money, you could have a pretty nice ride. Still, $7k is too much for a late '90s Cad. I'm only asking $5.5k for my '97 and still no bites.

JimHare
04-09-07, 01:51 PM
thanks for all the replies.they've definetly given me some added insight.one more question though;what are timeserts??


Timeserts (TM) are a steel insert threaded in to bolt holes in the (aluminum) block of an engine that has had its heads removed. They greatly increase the holding power of head bolts, and are pretty much REQUIRED when doing a Northstar HG ( and are probably not a bad idea ANYTIME you back headbolts out of an aluminum block and carve the hell out of the inner threads.)

There is a similar product called, I believe "Big Sert" but it does not have the same cachet as the actual TimeSert product.

jadcock
04-09-07, 01:55 PM
Jim is right. Thread bolt problems are often perceived by Cadillac folks as being a Cadillac problem, but the issue affects many different types of aluminum engines.

Just look at all the kits available for various Honda engines: http://www.timesert.com/html/honda.html

For GM in particular, there are kits for the Northstar V-8, the Shortstar V-6, the Ecotec 4, the LSx V-8 engines, etc: http://www.timesert.com/html/gm.html

Timesert also sells Ford and VW kits.

jholland
04-09-07, 03:22 PM
I had a 96 N* with 185,000 on it. I admit I neglected the cooling system and it got the illness. A good mechanic showed me the No. 3 spark plug was burning differently(plug washing). I flushed the system, replaced a leaking radiator and gave it a K&W headgasket job. Miraculously it worked. I put the tablets in a it worked for over 35,000 miles when a soccer mom broad sided it and ended its life.

I bought a 97 from a dealer who said it was in proper working order only to find out it had the illness. After a month of wrangling they bought it back.

I then found what was billed as a pristine 97 Aurora with 89,000. It was remarkably nice. I was more careful evaluating this one before purchase and found it had the illness. I pointed that little problem out and got the car for 1700.00. Fixed the heads and now have the quietest N* I've owned and the oil consumption is only half what my first one was.

The engine was baithed in oil. I replace the O rings on the crank sensors and it's down to a minor leak on the oil pan. Half case seal is dry.

I'll buy a N* with a bag head anytime if its an otherwise nice car.

JimHare
04-09-07, 10:24 PM
On another note, I'm not so sure that it's even mildly accurate to say "All Northstars leak (some) oil".. - my 99 Deville that I traded at 100K didn't leak a drop, and neither of my current ones do - the 155K Deville uses about a quart every 2000 miles, and the Eldo, for which I did a fluid 'n' filter change about 5 weeks ago at 75K, is at 77K now and the mark is about 1/4" below the full mark where I left it five weeks ago. Both cars are driven fairly hard, with 90% highway miles on our commutes. They both have Walmart Super-Tech 5w30 in them.

The Deville's average mpg, which my wife NEVER changes, is at 22.6, and mine is at 22.4.

Northstar? I can't complain. I put a new battery in the Eldo last year. That's the ONLY maintenance item it's needed in the 20K miles I've had it. I haven't even changed the friggin' wiper blades.

jadcock
04-10-07, 07:55 AM
My '97 leaks some. I think it's the oil pan gasket. After 157k miles, I would expect any engine to show SOME signs of external leakage. My '01 is bone dry. That was one of the prerequisites at purchase. Incidentally, I looked at a '97 STS with 70k miles on a car lot the other day, not to purchase, just check out. I peeked under and the oil pan was bone dry, with no leaks. So I agree -- it's easy to generalize all Northstars as having some problems that appear common, but it's really unfair to the group as a whole.

eldorado1
04-10-07, 11:19 AM
Okay, 98% of them 5 years or older leak oil. Happy?

;)

jadcock
04-10-07, 12:35 PM
Okay, 98% of them 5 years or older leak oil. Happy?

Not without real data. ;)

wydopnthrtl
04-10-07, 02:20 PM
I'm not a cadillac or northstar expert. But I am an OEM engineer with a hot rod heart. So take my opinion for what it's worth..

I say to buy a 00+ model and one that's without a doubt been taken care of. This is what I did about a year ago. Bought a 38k mile eldo, brought it home and did every possible fluid change. (except brakes which will be done soon) The life "blood" of any machine is it's oil / fluid. Reading plugs tells you a lot as well. Treat it with that respect and you'll be fine.

I've even pushed mine pretty hard with a 100shot of ramped up nitrous. But because I am beyond anal about safety of the drivetrain (octane, fresh fluids, plugs, and check everything all the time)... it's holding together just fine and I have nearly zero fluid usage. (no leaks at all) As is it uses about a qt of coolant every 6 months and a 1/2 qt of oil every 6-7k miles.

(62k miles and I shoot a 50shot couple times a month)

Rich

misfit6794
04-10-07, 08:54 PM
My experience with a northstar; Bought a 96 Deville with 81,000 miles. Changed all the fluids and I adressed everything that was neglected by the former owner, an elderly man. At 82,000 miles the head gasket blew, 3500 dollars later the engine ran amazing, the power is just awesome for a two ton car. The newer the car, the less the mileage, the less of a chance the former owner had to screw it up. Now, there are design flaws, the head bolts aren't long enough, hence they blow the head gaskets. The 4.9 if ignored, will also have cooling system issues though. My mechanic said it best, buying a used caddy is like playing russian roulette. Or you could look at it this way, the more complicated the car, the more parts there are to break. Or another point of view, after 1800 for the car and 3500 invested in it, it still needed an a/c compressor,shocks, and rear control arm bushings/control arm 1000 a piece and i needed two. Loved the deville, just couldnt afford it.

biggr101
04-11-07, 12:33 PM
ive always had a thing for devilles since my dad had his 97 concours.he hardly drove the car because he had a beater he used daily.he said that from the car sitting it developed oil leaks and it would run a little hot from time to time.likely the problem.it only had 48k on it.i drove it once from philly and instantly fell in love.i came across a nice 96 couple a months back off ebay.i went to see it.it was pretty clean,118k miles,started up with no noises or smoking.it ended up selling for 1100.i backed off because of the north* but i still want one.what ive learned here is two main related problems:threads pulling out of the block and headbolts too short.i wonder why they never had a recall to address this considering there's so many of them out there.

jadcock
04-11-07, 12:57 PM
what ive learned here is two main related problems:threads pulling out of the block and headbolts too short.i wonder why they never had a recall to address this considering there's so many of them out there.

:thehand:

Because the problem isn't as widespread as it is perceived. Of the millions of Northstar engines running reliably out there, a relative few will develop any problems at all. 1% of 1,000,000 is 10,000. If 10,000 owners came to you and said they ALL had headbolt problems, you'd think that was a sign that the engine was a real piece. That's in effect what happens with Internet forums -- folks have problems and come here to figure out what's going on. Of the thousands of members on this board, if only a few HUNDRED came here because of a headbolt problem, and all of those few HUNDRED posted about it, you'd think it was a pandemic. In reality, a few hundred represents a FRACTION of a percent of the total population out there.

To be sure, GM did change the headbolt design a bit for the 2000 model year. One could look at that change and conclude that they knew there was a problem with the prior design. Sure...any evolutionary design change could be interpretted that way. Cadillac also upsized the brakes for the 1997 model year, and also included a totally different lower control arm design, which was a mid-generation change for the Seville body. Could you or should you then conclude that the prior design was defective? No, not necessarily. Evolutionary design changes are a constant in the engineering world, as new ideas are perfected.

I wouldn't expect ANY manufacturer to recall every single engine, for a repair in the $2000 range, because of a failure rate of 1 in 100, or similar.

Unfortunately, none of us knows the true failure rate of the original headbolt design (or of the new headbolt design either for that matter), so I don't think any of us are really qualified to judge GM's design and lack of a recall.

clarkz71
04-11-07, 02:00 PM
Still, $7k is too much for a late '90s Cad. I'm only asking $5.5k for my '97 and still no bites.


:confused: Depends on the miles, I agree if it's 100k plus, $7000 is high. I thing I got a good deal on my 95 Eldo. I paid $6900 a year ago with 50,000 miles. It has 66,000 now and zero problems. Being a Florida car, no corrosion anywhere.

thatwolfofmine
04-12-07, 04:19 PM
I have a 96 DeVille. It overheats almost every day. I've had the radiator checked and there're no leaks. We use the DexCool and the tablets. A radiator specialist, who knows about Northstars checked the heads and said they were leaking, but not blown. Still it overheats almost everyday. The blower motor is gone though I just found out. So my heat/cool system isn't working. Could this cause it to overheat? Any suggestions?

jadcock
04-12-07, 05:16 PM
The "leaking" heads are what's causing it to overheat. If the headgasket is leaky, it's what we would refer to as "blown". Your HVAC fan has nothing to do with the overheating. It's the headgaskets. And repeated overheatings just make the matter worse. It'd be best to get the engine fixed, or replaced.

misfit6794
04-12-07, 07:02 PM
You have probably done some serious damage, especially dollar wise, driving the car in the condition. For it to overheat every day is probably frying alot of crucial engine parts, have you added oil? The oil in it is probably baked. I can't stress enough, do not drive the car anymore. you are probably looking at engine replacement. A radiator specialist doesn't know sh*t about northstars. What you need is an engine specialist, and a new mechanic.

boxhalr188
04-13-07, 12:02 AM
My '93 didn't use ANY oil between changes but the '98 Eldorado does. One of the reasons I bought the second Caddy was because of the Northstar engine, I love it (haven't had to put any money out yet)

Mountie
04-13-07, 12:58 AM
......and a post-'01(?) N* doesn't have any plug wires, anyway. It's COP (coil on plug) with insulated connector boots between the coil packs and double platinum AC Delco plugs, which are good for 100Kmi. (don't get anal or creative about the AC plugs. Search the spark plug threads....) If you read horror stories here regarding the N*, remember that those stories represent 1/10 of 1% of all N* engines out there........my 327 Chevelle had its share of bugs, too.......Z06, you threw away a great car.......hope you're not so antsy about aircraft engines........!

All's you need is a 1/4" socket set / & a few small boxwrenches for a turbine, correct?

Maintaining a Northstar is like any other engine. A bit of grease in the sparkplug boots, & use a flashlight to inspect the belts once in a while, change the oil & watch the coolant. Oh.... check the radiator hose clamps.

It's just a big Yamaha motorcycle engine...... in a tight space.

Ranger
04-13-07, 01:09 AM
Maintaining a Northstar is like any other engine. A bit of grease in the sparkplug boots, & use a flashlight to inspect the belts once in a while, change the oil & watch the coolant. Oh.... check the radiator hose clamps.
Actually, A/C Delco says NOT to use any dielectric grease as they come pre lubed.