IHADAV8.com - Turbo Buick Tech, and Nonsense

Tech Area => General Buick Tech => Topic started by: john robertson on January 31 2020, 01:48:07 PM

Title: oil question
Post by: john robertson on January 31 2020, 01:48:07 PM
I change my oil very frequently, usually at 1000 to 1200 miles. I've noticed for quite some time that it turns dark pretty fast, let's say at 300 to 400 miles. By the time I change it, it's pretty black and was wondering why. What's odd is that I have other turbo cars, and I follow the same regimen on oil changes, same oil, same filters, in fact, I might go up to 2000 miles on those cars, because I don't drive them as much or as hard as my GN, but the oil in those cars doesn't turn "black". It's not something I'm worried about because it runs great, but just wondering if there's any changes I could make to prevent this from happening.
Title: Re: oil question
Post by: Steve Wood on January 31 2020, 02:26:17 PM
I have not seen that difference between similar cars.  Normally, the color is a sign of the additive package reaction to heat and is not a sign of old or dirty oil.

My only thought is to send a couple of samples from different cars in for an oil test (mileage, etc. being similar) and see if anything is contrasted on the results.

It's an interesting question.
Title: Re: oil question
Post by: nocooler on January 31 2020, 02:47:56 PM
Excessive oil temps and combustion contamination can make it dark in a hurry.
1000-1200 is a little ocd in my opinion. What oil are you using? 

Title: Re: oil question
Post by: john robertson on January 31 2020, 05:04:21 PM
Ya know, oil's cheap and still, I could check to be exact, but it's at least a month between changes on my GN, much longer on the other two because I don't drive them as much. The brand doesn't matter because I'm getting different results with the same oil. Also, I have two oil filters on two of the cars via turbo-lubers.
Title: Re: oil question
Post by: john robertson on January 31 2020, 05:14:33 PM
I have not seen that difference between similar cars.  Normally, the color is a sign of the additive package reaction to heat and is not a sign of old or dirty oil.

My only thought is to send a couple of samples from different cars in for an oil test (mileage, etc. being similar) and see if anything is contrasted on the results.

It's an interesting question.


That's probably the only way I would know. I thought perhaps there was some common explanation for it like a PCV valve or something.
Title: Re: oil question
Post by: earlbrown on February 01 2020, 05:14:00 AM
Dump a can of Restore in there on your next oil change.



The black is carbon that makes its way past the rings into the crankcase (from burning hydrocarbons).

For funzies, do a compression and leak down test beforehand.     It never stops being odd seeing that stuff actually work.
Title: Re: oil question
Post by: john robertson on February 01 2020, 09:59:31 AM
Hey, thanks for that Earl. I'll have to try it. As I mentioned, the car runs terrific but have wondered for some time now why the oil darkens so quickly, noticebly at 300 miles. Compression Test? Leak down? I haven't even fixed my torque converter lock-up on my El Camino yet! GN is fine though. :)
Title: Re: oil question
Post by: john robertson on February 01 2020, 10:23:24 AM
Just read some positive comments about the RESTORE additive. Maybe I will run a compression test, and replace my plugs while I'm at it. Let you know what I find.
Title: Re: oil question
Post by: earlbrown on February 01 2020, 01:03:59 PM
Most people (including me) dismissed it as ''rebuild in a bottle'' snake oil.

but the science if valid.    Basically it's got a buttload of suspended microscopic aluminum.   If you look at a cylinder wall with a microscope all the millions of tiny scratches are very jagged and basically have millions of tiny glow plugs jutting out of them.   Since that's higher than the melting point of aluminum, they get 'tinned' like a soldering iron tip.  At that point the surface is smoother and the glow plug goes out.

Back in the 90's the owner of the Yamaha shop I raced out of had a friend that maintained a huge fleet of 305 Chevy pickup trucks for Auburn AL.   He was looking at having to buy something stupid like 45 crate engines because the trucks were all out of spec compression wise.     Just for the hell of it, he dumped a bottle of Restore in each one, put 500 miles on them and ran another compression test.

  Every single one of them was back up and now within 10% of each other.


Back then we didn't have youtube.   There's plenty of videos on there with people running that exact test and I haven't seen one that failed yet.



Now I'm not saying it'll fix a busted engine, but I've seen with my own two eyes it will help with ring seal.    And obviously, the worse the seal when you start, the greater the gains to be had.


I've been meaning to do a before/after on my GN since it's only got a couple thou on the engine I built about a decade ago.   I never think about  it since I change the oil about every 5 years or so. :)
Title: Re: oil question
Post by: john robertson on February 01 2020, 01:26:42 PM
Well, after reading some favorable reviews about it, I decided to do a compression check, and found my cylinders running between 130 and 140. I expected better, but it is what it is. Like I said, I'm quite happy with it's performance, but now, I'd like to see if this product will increase the compression as advertized.
Title: Re: oil question
Post by: Steve Wood on February 01 2020, 07:08:33 PM
Me, too!  😂
Title: Re: oil question
Post by: john robertson on February 02 2020, 09:09:47 AM
I had just changed my oil the other day, (I use conventional 20W50) and hadn't gone anywhere, so figured I'd go out and get some "Restore". Added it, and I guess I'll give it about 500 miles and then re-check the compression. Actually, I'll be shocked I tell you, SHOCKED, if my compression numbers increase.  :rofl:
Title: Re: oil question
Post by: Steve Wood on February 02 2020, 09:22:58 AM
)Another "Me, too!" but Earl is not the only guy that I know that swears by it :)
Title: Re: oil question
Post by: reality on February 02 2020, 09:41:39 AM
It will lower your temp 10 degrees. Actually seen on 2 tb's
Title: Re: oil question
Post by: Just a Six? on February 12 2020, 07:59:21 PM
I use anything on sale in 20-50 or 15-40 & mine does the same thing altho I only put that kind of mileage during a whole season. The motor is about 10 years old now with a good half a dozen track days so when it comes out in spring I'm going to check the compression & add a bottle to see what happens. I'll try to remember I'll post the results next fall. Glad you posted this up.   :cheers:
Title: Re: oil question
Post by: john robertson on February 13 2020, 09:02:02 AM
I use anything on sale in 20-50 or 15-40 & mine does the same thing altho I only put that kind of mileage during a whole season. The motor is about 10 years old now with a good half a dozen track days so when it comes out in spring I'm going to check the compression & add a bottle to see what happens. I'll try to remember I'll post the results next fall. Glad you posted this up.   :cheers:




Well, I'm thinking by about next week I'll have over 500 miles on my latest oil change which included the RESTORE additive, so I'll be performing another compression test very soon. Stay tuned! Here's hoping it does improve the numbers. Car's running great but oil is darkening as usual, but by next, only 500 miles till the next oil change.  :rock:  Maybe I'll even go to 600 miles. Who knows?
Title: Re: oil question
Post by: Scoobum on February 13 2020, 09:09:59 AM
Plugs colored normally...or are they black.
Title: Re: oil question
Post by: Steve Wood on February 13 2020, 09:55:16 AM
I believe that I read that if an oil is rated for 6000 miles, it should have used 50% of it's additive package at that time.  Some cars are rated for much higher mileage than that with specific oils being designated.

The types of additives used in a given oil have a lot to do with how soon and how dark the oils may turn. As I said earlier, only an oil analysis will determine if the oil is contaminated and with what.

An engine that was abused in it's past and which is full of sludge and other forms of "goo" will turn oil black almost instantly as the good oil detergents try to break it down.

An engine without a properly working pcv will turn the oil dark quickly.  I kinda doubt that most Buicks have properly working pcv's after we add breathers and such as they are sucking outside air thru the valves rather than crankcase air.  That leaves all the condensation vapor in the crankcase to be circulated and such vapors are very corrosive.  Again, only an oil analysis can tell what is going on once commonsense has been applied.

The famous 3000 mile change interval promoted by dealers, etc. is the easiest way to make money in a shop outside of the usual blatant robberies performed by shops.
Title: Re: oil question
Post by: earlbrown on February 13 2020, 12:29:12 PM
Quote from: "Steve Wood"

Quote
The famous 3000 mile change interval promoted by dealers, etc. is the easiest way to make money in a shop outside of the usual blatant robberies performed by shops.




 It's also a good thing if you're in the business of selling oil.  (or filters, since most people change filters on every oil change).

kinda interesting this thread popped back up.  I just came across the updated update video of a guy that used Restore in a Ford tractor.

I watched the one a long time ago where he posted the 5hr difference that raised/stabilized compression and cured the cold start problems.   
 He made a 100hr update and posted what happened in the last 95 hours.

 The data was pretty interesting.  The best cylinder to start with stayed the best and the crappy cylinders improved the most to even out the number.    On the second test, the crappy cylinders kept getting better and surpassed the 'good' one.
  And now the 'good' one is tied for last place.  And the shittiest cylinder ran right up to 2nd place.
  Granted, were only talking about a couple percentage points, but still pretty interesting.

https://youtu.be/VXIu3oo8z4c?t=303 (https://youtu.be/VXIu3oo8z4c?t=303)
Title: Re: oil question
Post by: john robertson on February 13 2020, 12:56:56 PM
Plugs colored normally...or are they black.






tan
Title: Re: oil question
Post by: john robertson on February 13 2020, 01:13:26 PM
Don't forget -- I have three turbo cars but only one has the dark oil "problem". All three have alcohol injection. One engine is stock with w/50s a TE44 and over 100K miles. No oil darkening "problem". Another has 35K original miles, is stock with 42s, and a TA49 and has -- no darkening. The engine with the "problem" has about 10K to 15K on it, has 80 lb. injectors, is .030 over with ported Champions and a JB 6262. So much fun!  :icon_lol: 
Title: Re: oil question
Post by: wmsonta on February 13 2020, 03:59:32 PM
Does the oil in the one car smell burned?
Title: Re: oil question
Post by: Just a Six? on February 13 2020, 07:43:23 PM
Steve you mentioned PCV & I clean mine now & then & it seems fine but I have a feeling it doesn't always work properly. Now & then when sitting at idle in the parking lot I'll rev it up a bit & get some smoke that I always thought smelled very rich & a sorta blue if I had to choose a colour to describe it. I'm going to take a real look at it this spring & see what's up on PL & SM. Hopefully I can make it do it while recording.
Title: Re: oil question
Post by: Steve Wood on February 13 2020, 08:49:38 PM
Valve guides or seals, or from the turbo would be my first two guesses
Title: Re: oil question
Post by: earlbrown on February 14 2020, 01:55:56 AM
Quote from: john robertson
 One engine is stock with w/50s a TE44 and over 100K miles. No oil darkening "problem". Another has 35K original miles, is stock with 42s, and a TA49 and has -- no darkening. The engine with the "problem" has about 10K to 15K on it, has 80 lb. injectors, is .030 over

So the only one that gets carbon in the oil is the one that's been bored....

  What rings do you have and what was the grit of the stones on the final finish hone?..


   If the answer is ''moly and I don't know'', odd are you have cast iron rings now.  (and found your problem).
Title: Re: oil question
Post by: Just a Six? on February 14 2020, 10:52:56 AM

Quote from: Steve Wood
Valve guides or seals, or from the turbo would be my first two guesses


I was hoping you wouldn't say that but I haven't touched this motor except plugs in about 12+ years (fresh in 08 I think) & beat on it at the track enuf times that I'll now have to take a serious look at it. The car always smells Rich at Idle & after it runs a minute with me near the exhaust I have to take my clothes off & air them out because they smell pretty much like oil & gas & it's been going on at least 5 years now. Oh well that's why I own all the tools so I might as well use them.
Title: Re: oil question
Post by: Scoobum on February 14 2020, 12:31:59 PM
You haven't driven the car enuf to wear out the guides. With the car sitting for as long as it has without being run regularly, then dollars to donuts the valve seals have dried out. I'll bet the 02 sensor is fukd as well. If the 02's are moving slower than 1 per second on the SM, then the 02 is on its way out. Make sure the Translator settings are set for your chip, and I assume that chip you have was burned for your combo. Idle BLM's with the couple of engines I had ran anywhere from 115-122 and the exhaust never smelled rich.
Title: Re: oil question
Post by: Just a Six? on February 14 2020, 02:21:38 PM

Brad I'm going to start a thread when I eventually get started checking things & your suggestions will be appreciated to help get it running the way it did when it was fresh. I just know one thing for sure that if heads are involved the engine is coming out. Really it's about time I show the car some love again anyways.


John I'm glad you started this thread & I hope you get your oil issue straightened out. For your sake I hope it's not the rings like Earl mentioned but he's pretty good & figuring out what's going on so BOL!   :cheers: . 
Title: Re: oil question
Post by: john robertson on February 14 2020, 03:02:34 PM


So the only one that gets carbon in the oil is the one that's been bored....

  What rings do you have and what was the grit of the stones on the final finish hone?..


   If the answer is ''moly and I don't know'', odd are you have cast iron rings now.  (and found your problem).


I don't know the answer to either the type of rings or the honing, so you're saying that the rings are worn to the extent that they allow excessive carbon by? Well, for me, as long as the engine's not smoking and performing as well as it is, it's not a problem. Can't worry about that unless it happens. I'm going to do another compression test this week and see if the Restore increased compression and will be posting the results here. Thanks for the Restore suggestion and thanks for your diagnosis, and thanks to everyone who chimed in.  :icon_smile:
Title: Re: oil question
Post by: earlbrown on February 15 2020, 03:34:36 AM
Moly rings are actually ''moly faced'' rings.    Moly is 60% porous so they require a VERY smooth bore finish as the rings will hold plenty of oil.

   Having a ''normal'' bore finish...    Most commonly referred to as ''a good crosshatch'', is a recipe for disaster. 

 When you have a ring face that holds oil, AND a scratched up cylinder wall that holds oil, you end up being unable to keep the two areas separated.  The only time you want any kind of oil holding ability on the cylinder walls is with something like a chrome ring.   And we don't run those in street TRs.

   The other downside is paying extra for the moly rings, just to have the bores physically scrape off the moly facing during initial startup.     The extra friction during the break-in process doesn't do good things to the rings ability to spring against the wall during high vacuum operation either.


  Moral of the story:  If the ring seal is crap, so is the oil life.  Blowing carbon into the crankcase makes oil black.
Title: Re: oil question
Post by: john robertson on February 15 2020, 08:45:06 AM
Well, thanks for the explanation. Makes sense. I couldn't find out those details as I bought the engine used and I found out from the seller that he himself did not assemble it. The machine shop did. I can't complain because I got it very, very, cheap! The heads and roller-rockers alone are worth twice what I paid for the whole motor. I'm sure I'll be OK as long as my compression numbers don't decline.  :)
Title: Re: oil question
Post by: earlbrown on February 15 2020, 02:58:44 PM
They shouldn't decline.   Once the engine is ''broken in'', it's pretty much done.

There's worse things in life than oil that turns black.
Title: Re: oil question
Post by: john robertson on February 17 2020, 03:58:27 PM
Just to finish up, I did an abbreviated compression test, testing only one cylinder which initially read 132 psi before adding the Restore. Unfortunately it still read the same thing after 600 miles with Restore. So much for that, at least in my experience, but it was worth a try.
Title: Re: oil question
Post by: earlbrown on February 17 2020, 04:57:28 PM
132 might not be that bad depending on your static compression and cam timing.
Since you didn't build the engine, there's no way to really know.

A leak down test would have been a better control, but that would require the use of my time machine now.
Title: Re: oil question
Post by: TexasT on February 17 2020, 06:24:23 PM
I'd do the leak down now and see where you are. And I wouldn't feel bad about the 132 psi. More boost fixes a lot of ills. 
Title: Re: oil question
Post by: Top Speed on February 18 2020, 06:08:53 PM
very informative thread
Title: Re: oil question
Post by: john robertson on February 19 2020, 05:38:01 PM
I'd do the leak down now and see where you are. And I wouldn't feel bad about the 132 psi. More boost fixes a lot of ills.


It's a minor issue, and I'm not really concerned, because, my immediate thought was, as you say, just turn up the boost to compensate for lower compression, and maybe like Earl has suggested, it's due to cam timing. It's a 212-212, by the way. If my compression was higher, I'd just have knock at lower boost. I'm running at 21 lbs of boost now with a 6262 turbo w/ DIY alky, with no knock. I'd turn it up, but the incidence of challenges out there, for me, anyway, is so low, I'm just not motivated to do so. Hell, I just took off my 20" wheels and gained at least three car lengths out of the hole. :D
Title: Re: oil question
Post by: earlbrown on February 20 2020, 12:34:15 AM
If I'd known you had 20" wheels, I'd saved you a lot of trouble



...and never replied at all.




Glad to see you're getting warmer to having an actual car that may, or may not, run right.