Northstar V8 Oil stories..
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I've got a 2006 Buick LuCerne with the Northstar V8. Owners manual calls for oils that meet GM 6094 (dino SM), 5w30.
I've been running SuperTech 10W30 dino since I had it and it runs as quiet and smooth as can be. I have 50,000 miles on it now. My only complaint is that it is a gas hog.
I've been running SuperTech 10W30 dino since I had it and it runs as quiet and smooth as can be. I have 50,000 miles on it now. My only complaint is that it is a gas hog.
Originally Posted By: 440Magnum
Originally Posted By: Trav
This is a common N* complaint.I had the same issue on my 99 as well as a quite a few others.Nothing being sucked/sprayed down,added to the oil etc will cure it.
Remove all the plugs when its warm,pour 1/4 of a bottle/can (non aerosol) of GM top engine cleaner down each plug hole.
Replace the plugs and leave it overnight or min 12 hrs.
Start the motor (it will probably run terrible)
You forgot this step right before start the motor:
-Pray that enough of the stuff drained past the rings so that you don't hydro-lock it, push a head off, and rip the fragile Northstar head bolt threads right out of the block
I would rotate the engine 2 full turns by hand before risking starting it up if it were mine. If its too hard to reach the crank pulley to turn it with a wrench, wait till the 12 hour soak is over before re-installing the plugs and spin it with the starter with the plugs out to clear all 8 holes before you start it. Northstars are fragile enough as it is, I wouldn't play with fire.
I can see that being a concern but with only 3 fluid oz in each cyl for a min of 12 hrs it hasn't been an issue,it seems to get past the rings quickly.Better safe than sorry i guess.
It does make a mess of the oil though.
Originally Posted By: Trav
This is a common N* complaint.I had the same issue on my 99 as well as a quite a few others.Nothing being sucked/sprayed down,added to the oil etc will cure it.
Remove all the plugs when its warm,pour 1/4 of a bottle/can (non aerosol) of GM top engine cleaner down each plug hole.
Replace the plugs and leave it overnight or min 12 hrs.
Start the motor (it will probably run terrible)
You forgot this step right before start the motor:
-Pray that enough of the stuff drained past the rings so that you don't hydro-lock it, push a head off, and rip the fragile Northstar head bolt threads right out of the block
I would rotate the engine 2 full turns by hand before risking starting it up if it were mine. If its too hard to reach the crank pulley to turn it with a wrench, wait till the 12 hour soak is over before re-installing the plugs and spin it with the starter with the plugs out to clear all 8 holes before you start it. Northstars are fragile enough as it is, I wouldn't play with fire.
I can see that being a concern but with only 3 fluid oz in each cyl for a min of 12 hrs it hasn't been an issue,it seems to get past the rings quickly.Better safe than sorry i guess.
It does make a mess of the oil though.
I had a 2000 Deville up until about six months ago. About three years ago and with about 110,000 miles on the odometer, its Northstar developed a pronounced knocking sound when started cold. It wasn't a lifter tick - it sounded more like tiny hammer blows down inside the cylinders from what I could tell. A duller sound than lifter or injector tick that seemed to come out of the block from my critical listening tests, in other words. It would continue from 30 seconds to a couple of minutes, depending on the temperature outside. I'm in Florida, so by "cold" I mean in the 40s and sometimes as low as the 30s.
I diagnosed the noise as a carbon issue and gave it a double treatment - from above and below - with a cleaner I have used many times in the past called Marvel Mystery Oil (aka MMO). I put a quart and a half of MMO in the crankcase with six quarts of Rotella 30 weight from Tractor Supply for a 20% MMO mixture and put double the recommended (8 or so oz per 10 gallons) in the gas tank with a fill up. It worked. Every day the rapping grew fainter until, after about a week, it went completely away. I never heard it again. I sold that car with over 160,000 miles on it and it ran great when I last drove it. I don't know whether it was necessary to treat both the oil and the gas, but I know that it worked and that it didn't hurt anything.
The only downside is that the MMO in the crankcase made the gasket leaks that my 2000 had worse and put some drip stains on my driveway. Oil consumption went back to normal when I did a change after about 1000 miles.
One factor I should mention is that the carbon problem started after about five years of being driven gently by my wife on short trips. There are many accounts of Northstars developing carbon issues like that. I drove the car the remaining years we had it and I have about 25 miles of interstate driving in my daily commutes. Maybe that had something to do with the noise never coming back.
I'm not sure from the description in the post that we are talking about the same noise, but I wanted to pass this along in case it might help. By the way, I have known of MMO treatments curing valve lifter ticking more times than I can remember. It is something that I have been using for over 40 years.
I diagnosed the noise as a carbon issue and gave it a double treatment - from above and below - with a cleaner I have used many times in the past called Marvel Mystery Oil (aka MMO). I put a quart and a half of MMO in the crankcase with six quarts of Rotella 30 weight from Tractor Supply for a 20% MMO mixture and put double the recommended (8 or so oz per 10 gallons) in the gas tank with a fill up. It worked. Every day the rapping grew fainter until, after about a week, it went completely away. I never heard it again. I sold that car with over 160,000 miles on it and it ran great when I last drove it. I don't know whether it was necessary to treat both the oil and the gas, but I know that it worked and that it didn't hurt anything.
The only downside is that the MMO in the crankcase made the gasket leaks that my 2000 had worse and put some drip stains on my driveway. Oil consumption went back to normal when I did a change after about 1000 miles.
One factor I should mention is that the carbon problem started after about five years of being driven gently by my wife on short trips. There are many accounts of Northstars developing carbon issues like that. I drove the car the remaining years we had it and I have about 25 miles of interstate driving in my daily commutes. Maybe that had something to do with the noise never coming back.
I'm not sure from the description in the post that we are talking about the same noise, but I wanted to pass this along in case it might help. By the way, I have known of MMO treatments curing valve lifter ticking more times than I can remember. It is something that I have been using for over 40 years.
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Update... ( I said I wasn't going to post, but would like to get the info out to Northstar OWNERS and HELPFUL folks. )
MPG is up over 20 even with normal 80+ for over an hour a day. ( can get 24 if I keep it under 70 ) Best it has ever run. 62K on the clock.
This car MUST run 91+ fuel or will get CPS codes and P0340/41 cat codes.
Funny thing is when I tried to run 89, the tick got very quiet. In fact, I took it in to have the CP Sensor swapped out and while the part was on order, It was dead quiet and not one code, even with 87 fuel.. Seemed to have a lack of sack.. But quiet to the point of silent.
Once the new CPS went in, don't even try to run anything but 91+ or get the same codes again. Great mileage and a ton of get up and go, but the same tick .
So.. This leads me to think it is timing related or code ECU.. With advance and retarding making such a big swing, and how hard I drive this car, throw in the fact that it is a known caddy issue.
"Betcha, it's the cam chain adjusters making the noise. MMO ain't helping that. "
I think is dead on.
30% on the OLM.
I might see about getting the chain adjusters done. Will post back after that.
MPG is up over 20 even with normal 80+ for over an hour a day. ( can get 24 if I keep it under 70 ) Best it has ever run. 62K on the clock.
This car MUST run 91+ fuel or will get CPS codes and P0340/41 cat codes.
Funny thing is when I tried to run 89, the tick got very quiet. In fact, I took it in to have the CP Sensor swapped out and while the part was on order, It was dead quiet and not one code, even with 87 fuel.. Seemed to have a lack of sack.. But quiet to the point of silent.
Once the new CPS went in, don't even try to run anything but 91+ or get the same codes again. Great mileage and a ton of get up and go, but the same tick .
So.. This leads me to think it is timing related or code ECU.. With advance and retarding making such a big swing, and how hard I drive this car, throw in the fact that it is a known caddy issue.
"Betcha, it's the cam chain adjusters making the noise. MMO ain't helping that. "
I think is dead on.
30% on the OLM.
I might see about getting the chain adjusters done. Will post back after that.
Yet another update...
The intake bolts where all loose. Could spin with fingers. Common on Northstar. After snugging those down, Cat code P0430 would come up quick. replaced 1 o2 and swapped sides. Problem did not move. Still the same code.
GM replaced 1 Cat. Now the car has never run this bad.
Bad idle and CPS code 340 & 341 are back. even after CPS being replaced. Still pointing to timing issues.
Back to the dealer again.
The intake bolts where all loose. Could spin with fingers. Common on Northstar. After snugging those down, Cat code P0430 would come up quick. replaced 1 o2 and swapped sides. Problem did not move. Still the same code.
GM replaced 1 Cat. Now the car has never run this bad.
Bad idle and CPS code 340 & 341 are back. even after CPS being replaced. Still pointing to timing issues.
Back to the dealer again.
oh the joys of the northstar. im glad i left the caddy dealer years ago. i never seen so many engines of any make or model in any brand of any car get replaced or repaired as often as the northstar. if it's not a complete engine re-seal from the stupid gasket/seals/crank case design, or stripped out head bolts it's the stupid engine/piston design that causes noises.
the noise you are probably hearing is piston slap. the cylinder go out of round causing oil consumption and carbon knock.
the noise you are probably hearing is piston slap. the cylinder go out of round causing oil consumption and carbon knock.
Originally Posted By: IndyFan
Originally Posted By: steve20
The funniest thing I can think of is
"Mobil-1 is a quality oil"
Steve
Not laughing. You sound like a Bitog lemming, with that line. Ok, maybe I'm starting to grin now...just a little.
Lemmings!! Mobil 1!!
Seems Carbon build-up casues Lifter tick. Check. Also do a Piston Soak with SeaFoam!
demarpaint, care to come defend MMO?
Originally Posted By: steve20
The funniest thing I can think of is
"Mobil-1 is a quality oil"
Steve
Not laughing. You sound like a Bitog lemming, with that line. Ok, maybe I'm starting to grin now...just a little.
Lemmings!! Mobil 1!!
Seems Carbon build-up casues Lifter tick. Check. Also do a Piston Soak with SeaFoam!
demarpaint, care to come defend MMO?
Originally Posted By: HangerHarley
demarpaint, care to come defend MMO?
Defend MMO, why? It has a pretty good rep here on Bitog lately. Seems like the OP tried everything. Here is a quote that sums it up well.
Quote: Try just driving it and quit trying to remanufacture the engine with liquids. It obviously has some mechanical components that make the noise and need to be remedied.
The OP also said: Quote: Here is what I have found. The ticking, tapping, clacking on a very warmed up motor, was only quiet on a dino 10w40 5qts 5w20 2 qts and MMO, but it used a qt. (Seems to me it worked, I'd try it with the 10W40 and skip the 5W20 next time, maybe it won't burn off.)
Besides the people that hate MMO have made their minds up. I suggest they don't use it. If they did they'd be looking to find fault with it, after all that is human nature, isn't it? LOL
Here's a thought why don't you defend MMO? You seem to enjoy
demarpaint, care to come defend MMO?
Defend MMO, why? It has a pretty good rep here on Bitog lately. Seems like the OP tried everything. Here is a quote that sums it up well.
Quote: Try just driving it and quit trying to remanufacture the engine with liquids. It obviously has some mechanical components that make the noise and need to be remedied.
The OP also said: Quote: Here is what I have found. The ticking, tapping, clacking on a very warmed up motor, was only quiet on a dino 10w40 5qts 5w20 2 qts and MMO, but it used a qt. (Seems to me it worked, I'd try it with the 10W40 and skip the 5W20 next time, maybe it won't burn off.)
Besides the people that hate MMO have made their minds up. I suggest they don't use it. If they did they'd be looking to find fault with it, after all that is human nature, isn't it? LOL
Here's a thought why don't you defend MMO? You seem to enjoy
Originally Posted By: HangerHarley
Lemmings!! Mobil 1!!
That is some irony right there. That is the pot calling the kettle black.
Lemmings!! Mobil 1!!
That is some irony right there. That is the pot calling the kettle black.
Originally Posted By: ZGRider
Yeah, the "brand" of oil you use is going to make the engine overcome any mechanical problems it may currently have.
My MB 190e has worn cam chain adjusters, I bet if I run AutoRX, the noise will go away magically. Or maybe if I use Mobil 1? I wonder what oil would make it so I don't have to adjust the valve clearance and make that noise go away too?
No oil is going to fix engine mechanical issues. Most engine noises have their origin in some defective or deficient component. You can't fix mechanical problems by changing oil brands or running a "cleaner" thru your engine.
Find out what is causing the noise and correct the problem (if there is one) and then choose oil to prevent future issues.
Couldn't have said it better myself.
Changing oils might mask it slightly or defer explosion a bit, but no fluid is going to magically fix poor design.
Yeah, the "brand" of oil you use is going to make the engine overcome any mechanical problems it may currently have.
My MB 190e has worn cam chain adjusters, I bet if I run AutoRX, the noise will go away magically. Or maybe if I use Mobil 1? I wonder what oil would make it so I don't have to adjust the valve clearance and make that noise go away too?
No oil is going to fix engine mechanical issues. Most engine noises have their origin in some defective or deficient component. You can't fix mechanical problems by changing oil brands or running a "cleaner" thru your engine.
Find out what is causing the noise and correct the problem (if there is one) and then choose oil to prevent future issues.
Couldn't have said it better myself.
Changing oils might mask it slightly or defer explosion a bit, but no fluid is going to magically fix poor design.
I still think that it is related to the VVT not doing it's job. Weight of oil plays into that, no ? But I still think it is a timing chain issue.. weather a connection is bad and not allowing correct advance and retard of ignition. Thus the CPS codes. I had to get under the car and get the exhaust off the cross frame bracket.. The rumble could be felt thru the whole car.. One more year with this car and I think I am going back to Jaguar. Motor does not use any oil and there has been nothing in the pan other than oil for over 20K.
Originally Posted By: lipadj46
Originally Posted By: HangerHarley
Lemmings!! Mobil 1!!
That is some irony right there. That is the pot calling the kettle black.
Just found out what a Lemming was. Seems this was most humorous.
Originally Posted By: HangerHarley
Lemmings!! Mobil 1!!
That is some irony right there. That is the pot calling the kettle black.
Just found out what a Lemming was. Seems this was most humorous.
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