: New bearings, new rings, 1000 miles and still burning oil

08-10-10, 10:58 PM
Ok. I'm about 1000 miles into this rebuilt engine. Can anyone tell me why I would still be smoking? It smokes terribly when I downshift and anytime I am braking after exiting the interstate or after traveling at high speeds. 99 Seville STS. Here's what was done:

Jakes head kit installed
new rings Sealed Power
New bearings (main and rod)
New gaskets upper and lower
Heads pressure tested before installing. Tested ok.
Ran it at less than 3500 rpm first 500 miles. (very difficult for me)

I was told by the mechanic that it would probably take a while longer for the rings to seat since they aren't cast steel. Anyone know what I should do. One guy told me b/c these are the type of rings I need to pour drano down into the engine. Another said put some type of pellet and cold crank the engine to seat the rings. Another said drive the hell out of it. I'm confused. What should I do. I'm this far >-< from parting it out and buying another seville that already runs. Ugh!!!! One with a/c too. LOL.

08-10-10, 11:09 PM
can the egr system cause this to occur?

08-10-10, 11:11 PM
can the egr system cause this to occur?


08-10-10, 11:13 PM
I have no answer, but why in the hell did you replace the rings and bearings? The lower end will last til the car rusts into a pile of dust.

08-10-10, 11:33 PM
I know. The mechanic told me I needed this. :(

08-10-10, 11:34 PM
The rings were a mess. Water had gotten into the engine. The rings were stuck and walls had some rust (weren't pitted tho).

08-10-10, 11:38 PM
I may have to start over and get a whole new engine I suppose. This one I will do completely myself rather than waste 1400 dollars paying someone who doesn't know what they are doing only to stud the engine and redo the lower end. The original bearings all looked good too when he removed them. Not many good mechanics in the area here. I may just try and see if Jake has an engine he will sell me, save my money up and do it that way. Very disappointed.

08-11-10, 06:11 AM
Micah - please contact John Livingston (also has a thread about a damaged crossover in the Northstar section) and ship that spare crossover you have to him please - I will pay for the shipping because I promised John one a while ago and never got to it (I feel so bad)-

UPS shipping kind of didn't tell me the full truth - engines are still costing me $400-$600 to ship after all is said and done. If you're interested in one; and have about 2-3 weeks to receive it, and can pay me now, I'll waive the shipping costs. That 2-3 week advance on money is worth a lot to me right now. It won't smoke or overheat, it'll run like a champ and it will be all remanufactured, studded and re-sealed. $3950 to your door. Subtract $50 to please ship that crossover to John- $3900 even. I pay the duties and taxes. I need to order some exhaust valves and bearings before I can build it up.

Ranger - the odd Northstar does need bearings and at least have the pistons removed and rings/grooves cleaned manually. On higher mileage units, the exhaust valves need to be ground or replaced. Quite often the exhaust valves have such deep pits in the seat area that machining is not an option - you run out of valve material. And while the bottom end is almost bulletproof, I've seen a few that have had scoring and pits in the bearings and replacing them in time will prevent the need for crank machining. I think for the most part, bearing condition relies heavily on oil change intervals, oil type, and not overheating too much...

08-11-10, 08:14 AM
I already shipped it. I shipped it yesterday.

08-11-10, 08:23 AM
This project has pretty much soaked up all my money. LOL. It'll have to wait. I emailed you about it. I have about 3000 into this engine alone already. Seriously. Anyways, I can't pay now. I might just drive it up there, smoking and all. LOL. My bumper is black from the dang smoke coming out.

08-11-10, 08:23 AM
Love road trips. LOL

08-11-10, 10:58 AM
Burning oil after coastdown isn't rings - it's valve stem seals. Were the heads disassembled and checked ? Cams and cam followers ("lifters") inspected for excessive wear ?

Don't pour anything into the engine - not even seafoam. None of that will give you anything but grief.

Piston rings aren't spring or cast steel - they're cast iron. The oil control scraper ring may or may not have spring steel side rails or a waffle pattern backing ring.

......and exactly where is the oil level on the dipstick - right now ???

<------- ADD ?????????? OPERATING RANGE -------------------O

08-11-10, 12:41 PM
<low-[x------]=======. X marks the spot. Not quite in low but also not normal. The rings are sealed power. Waffle design on the oil scraper. I had heads tested. Not rebuilt. Tested ok so didn't rebuild at machine shop

08-11-10, 12:42 PM
Compression test came back 127 to 140 compression

08-11-10, 02:41 PM
Burning oil after coastdown isn't rings - it's valve stem seals.

Glad to know that. But what causes a huge puff at acceleration after idling for for 5+ minutes?

Miwise i usualy top up and hit the reset on the trip meter to watch oil consumtion. Just wait till is says "check oil level" then do the math. How fast can valve stem seals lose your oil?

08-11-10, 03:03 PM
It was in the middle of ok range day before yesterday after oil change. Now needs oil again 100 mi later bc it's already low.

08-11-10, 03:51 PM
Ok. Talked to the guy who pressure tested the heads. He seems to think that the rings were improperly installed by my mechanic. he doesn't think the heads are bad. Said the rings could have been installed upside down or a number of other things. He doesn't think its the heads because of the sheer amount of oil its producing.

08-11-10, 04:09 PM
OK - I didn't go there: If the oil rings are installed upside down all 8 pistons literally act like an oil pump and, yes, you will burn oil at an incredible rate. Oil rings are tapered - by only a couple of thousandths of an inch, but they're designed to act as a scraper on the downstroke.

If the oil rings were installed upside down that's not your labor or repair problem. The new ring package instructions are very specific on where and how to install each ring.

08-11-10, 06:16 PM
I talked to the guy who installed them. Of course he says he installed them correctly but I'm not so sure. I'm very annoyed. Ugh. I paid him a lot of money. I guess the only thing I can do is to either sue him or to trash the car b/c i'm so sick over the whole ordeal its just incredible. I may put it to the side a few months until I cool down about the whole thing and just park it for now. I can keep driving my mustang until I get around to it. BTW. Would the engine even have compression if the rings were upside down? just curious.

08-11-10, 06:37 PM
Sure - some upper compression rings are stepped in order to allow combustion pressure to literally "push" the ring into intimate contact with the cylinder wall. You install them upside down and you still have compression -

BUT there's a hint here - your earlier post says compression of 127 - 140 psi. That is uniformly about 20 psi low for your year Northstar. Something is amiss, and with new rings and checked heads the compression pressures should be a LOT closer together than 13 psi.

08-11-10, 07:21 PM
Ok then. What about the honing of the engine? He honed it out with a centrifugal hone bit he attached to his drill (not quite sure what to call the thing, but the centrifugal motion pushes it against the piston walls). He did this to each cylinder. Just knocked off the rust (the old rings were stuck). So. . . could the hone job have caused this then? I'm stumped. I guess the only way to know is to either stick a bore scope into the thing or to literally redo the entire job (which i refuse to do). LOL. I'm more willing to sell the car to a junk yard and try to find another one than to reattempt all of this. Work has picked up too so I really don't have the time anyways nor the resources. If only foresight were 20/20. :-(

08-11-10, 07:51 PM
Your mechanic messed up the job.
No ifs, ands or buts.
I'd put my next $ into a lawsuit if I were you.

08-11-10, 09:21 PM
Is it possible it's just having trouble breaking in? I guess what I'm asking is it worth pulling out again or should I just drive it and maybe it'll stop eventually?

08-11-10, 09:57 PM
Yeah. I'm not going to sue. I really don't have the money nor time for any of that. Next time I go straight to jake if there is a next time. I'm just gonna get one of his engines if I have this problem again. That's if I get another sts. I'm looking at an 01 STS. Haven't driven it yet. I'm going to see if I can trade my mustang in on it. My mustang is really a sweet ride but it's just not the type of car I like to drive. My car also seems underpowered a bit on take off if I give it a lot of gas. like the engine has trouble revving up. Of course all this smoking I suppose could have wrecked my catalytic converter.

08-12-10, 12:07 PM
Yeah, I agree, this "mechanic" was not much of a mechanic. Because the Northstar do use oil there is absolutely no reason to hone the cylinders. Usually even at 200K plus, when taken down you can still see the factory crosshatch hone pattern and there is no ridge to cut. Sounds like this guy screwed your engine up royally.

08-12-10, 02:18 PM
Yeah. Oh well. I remember Seeing the crosshatches u speeck of. I saw it before and after he honed it. What should he have done? To remove the rust. Some of the rings were stuck to the cylinder walls

08-12-10, 02:19 PM
I agree he's not much of a mechanic tho. Next time I drive to Canada. Lol

08-12-10, 04:17 PM
Yeah. Oh well. I remember Seeing the crosshatches u speeck of. I saw it before and after he honed it. What should he have done? To remove the rust. Some of the rings were stuck to the cylinder walls
Hard to say without having seen it, but I doubt it was all that bad. I think the biggest problem is that he may have installed the rings (or some of them) upside down, but you will have to open the engine to prove that.

08-12-10, 05:13 PM
Lots of variables here, but know that the Northstar uses a very dedicated and specific hone grit and crosshatch angle - the service manual is very specific on this. IF the cylinder work were done correctly there would be literally NO piston ring break-in - have you ever heard of a new car (off the showroom floor) being returned to the dealer because the rings "won't break in" ?? A point, yes, but germane.......The Olds 455 engines I build will consume maybe a half quart of oil in 100 hours from new rebuild, and that's using standard old Sealed Power moly rings.

Something's fishy, and it's not your - or the engines' - fault.

08-12-10, 05:32 PM
One of the arguments against reringing a NorthStar in the field is that the factory honing job is critical and done with diamond tooling. It's a two step process; first with coarse stones to produce channels that will hold oil and second with fine stones to produce plateaus that will provide a surface for the rings to slide on. That being said, a NorthStar design engineer indicated that the majority of the oil consumed by the engine went by the rings in the grooves in the pistons and not between the rings and the cylinders. Piston groove wear was death on oil consumption.

08-12-10, 08:44 PM
Yeah. I'm thinking that it is likely the honing job that caused the problem. Btw. I revisited my receipts today. It wasrock product rings I had installed. I went upon the suggestion of the mechanic. Anyways. Trying to work a deal to get a 2001 Seville sts. I'm so sick over this I reallydont wanna mess with thiscar any longer. Lol

08-12-10, 08:48 PM
Of course there's truly no way to know without tearing it down. Not sure I feel like doing so without a guarantee it'll work. So I'm thinking I'm going to abandon this project. Just gonna find me another sts. Newer

08-12-10, 09:00 PM
Micah, can you pull the engine and strap it to a skid/crate it? I'll handle the pick-up of the engine and all of the paperwork, in a couple weeks you'll get an engine back that will run good and won't consume any more oil than your average Northstar. The bill will be lower because there will be some gaskets I can re-use, since most are new right now (cam cover, oil pan (maybe)) and the studs are already in.

I try to help people out when I can. So if you're willing, pull that engine, I'll do the work, and pay me after you get it back and only if it's consuming oil to your satisfaction (which means harly any at all). If I receive payment 30 days from the date I ship it back to you, I'll be fine with that.

I'm just a little upset that someone would screw up your engine job the way they did. It needs to be corrected and you don't need to get another car because of this. If you're willing to do the remove and reinstall, I'll get you going again.

08-12-10, 09:03 PM
This time it will have either new or re-ground exhaust valves and seats, possibly guides, new valve seals, better rings, and the correct hone pattern/finish.

08-13-10, 08:40 AM
Jake, are you Superman?

miwise, if the rest of the car is in good working order, fix the engine and drive her off into the sunset, this isn't worth putting her out to pasture over.

08-13-10, 01:01 PM
Yeah. The rest of the car is ok. I can probably do that. That is very generous of you Jake. I will call you as soon as I get back on land again.

08-13-10, 01:24 PM
Jake - you show a true passion for keeping these cars on the road - one that transcends your business goals. You're a good man!

Richard Moore

08-13-10, 03:23 PM

08-13-10, 05:05 PM
Hmmmm. Yet another interesting read. Sounds like the only way to find out is to tear down the engine and check everything. We shall see. Hopefully in the next few days I can begin investigating some of these things after I get home.

08-14-10, 01:50 AM
No I'm not Superman :D If I were I'd be caught up with the HG jobs on my list already :)

Thanks Tateos and STSs, rule of thumb in life is to treat everyone like a good neighbor and friend unless they give you a reason not to. I've had a few customers who I'd prefer never to see again but so many of my customers have become friends. I heard from my 2nd HG job customer two nights ago. He's having some issues with his '99 Deville not starting. Beautiful black beast of a car. We chatted on the phone for a while. He hasn't changed the fuel filter in the 5 years that he's owned it so I'm thinking that may be the cause.

Sometimes I get tired of always working but cars have always been my passion and since I started to familiarize myself with Cadillacs, especially the mid 90's+ when GM decided "Cadillac needs some sport and more style packed into these beautiful 4000lb luxury cars", I fell in love with them. I bought my '97 Eldo after my dad bought his '92 Deville. That Deville was smooth, comfortable, quiet, and pretty quick. When I tore down my '97's engine to do the HG's, I looked at the design work and engineering that GM put into these motors. The Northstar not only looks great and runs great, they are designed to last a very long time; with the exception of the HG issue that so many are experiencing. They make great power on very little fuel, run smooth past 6000 rpms, and most of these 4000 lb cars can leave rice-rockets in the dust. They hold their own against almost anything on the road, if you consider the fact that these are 4000 lb. full size cars built from steel. A tiny tin can with little-to-no weight may take these cars in the 1/4 mile, but we're riding in style. I got smoked in the 1/4 by a Cobalt SS. Do I feel bad? 14.95 out of a black on black bone stock STS with 260,000 kms on it, I think it did pretty damn good.

08-14-10, 01:52 AM
Micah whatever you decide, I'll do my best to help. Sounds like you're on vacation! Enjoy man!

08-14-10, 02:51 AM
Lol. Kinda. I'm at work. Sometimes u have to just get away from it all.

08-14-10, 07:14 PM
to home and back between jobs. No smoke hardly at all. Smells kinda rich. Maybe bc getting oxygen sensor code. Bank 1 sensor 3. Which sensor is that? I know where bank 1 is but don't understand why they have codes for 3 sensors for each bank. Also has a bit of rough idle. Maybe oxygen sensor. Also a little sluggish when u first hit the gas. Hesitation. Don't know if all these symptoms are related to the previous smoking engine or what.

08-14-10, 10:48 PM
Which sensor is that? I know where bank 1 is but don't understand why they have codes for 3 sensors for each bank.
You don't. There are 3 on bank 1 and 1 on bank 1. Bank 1 sensor 1 is on the manifold. Sensor 2 is the pre-CAT sensor and sensor 3 is the aft-CAT sensor. Pre-CAT sensor was dropped in later years. Bank 2 only has 1 sensor. It's on the manifold.

08-15-10, 03:34 PM
Must be the aft cat sensor acting up I suppose. I knew I had one on each manifold and 1 after cat making 3 total. Makes sense. Guess these codes are generic and all don't apply to my car.