Stuck Rings

[wiswind]

Direct Injection (DI) in gasoline engines is another can of worms.
One problem is that the PCV junk still goes into the intake and over the intake valves.
All the detergents in the fuel bypass the intake/intake valves and intake valve seats, so the detergents (even the ones you add) in the fuel are not able to keep them clean.
A system of keeping the valves clean is an issue for DI engines.

 

[bulwnkl]

Originally Posted by CR94
Originally Posted by bulwnkl
The TEOST MHT-4 test is part of the certification testing for API or ILSAC, and it's about piston ring cleanliness. I've posted on the board recently links to data sheets from a company that actually publishes their MHT-4 test results. From that company, 0W20 leaves 3x as much deposit on the MHT-4 test as the 5W20 grade from the exact same line of oil. ...
As I understand, 0W-20 is exempted from that test that most thicker grades must pass. I'm not sure about 0W-16 or 0W-30.


The 0W20 grade is exempted from TEOST 33c, which is a turbocharger deposit test. It must still undergo MHT-4, the ring deposit test, it just doesn't do nearly as well as 5W20.

I don't have a nice chart of both tests _and_ passing requirements for GF-6A or B yet. Do you know of one?

 

[D1dad]

I wish it was as simple as upkeep. 09 Nissan, services every 3500-4K with some sort of synthetic and it's a burner. I've got a pint of kreen in the oil and one in the fuel right now but have little faith it will help.

 

[CR94]

Originally Posted by bulwnkl
... The 0W20 grade is exempted from TEOST 33c, which is a turbocharger deposit test. It must still undergo MHT-4, the ring deposit test, it just doesn't do nearly as well as 5W20.
I don't have a nice chart of both tests _and_ passing requirements for GF-6A or B yet. Do you know of one?
Thanks for that info.
Considering how common ring coking seems to be in some modern engines, we need more discussion of the MHT-4 test, which is rarely mentioned---until you did.

No, I don't know of such a chart, although one must exist.

 

[Germanium]

It is false that oil base type can't have remarkable difference in ring sticking. I had a Yamaha XS 500 which were known to have ring sticking issues stick rings while using Castro GTX 20/50 unstuck in very short order when I used Amsoil 20/50 synthetic which had a high diester synthetic base. It did this within 30 seconds of first start after the switch to Amsoil. This engine ran really bad with lots of missing & excess oil burning. This all stopped almost instantly with the Amsoil.

Diester synthetic base stocks are known to have extremely high solvency compared to any other oil base type except polyolester which is about the same. This can indeed clear stuck rings in short order.

It also clings to hot surfaces better as evidenced by better starting with hot air cooled engine such that instead of engine binding & stop turning over if I opened throttle during cranking hot engine as it did with the Castrol with the Amsoil it actually sped up when I opened the throttle when cranked hot. Lesson here is the Castol GTX at that time did not keep to the metal surface sufficiently when hot causing binding & seizing where with the Amsoil the greatest restriction to cranking was the vacuum caused by the closed throttle as cranking actually sped up when I opened throttle instead of seizing.

 

[Mad_Hatter]

Originally Posted by Germanium
It is false that oil base type can't have remarkable difference in ring sticking.

It's not a demonstrably false statement given what, 99% of commercially available lubes are not majority PAO/POE based lubricants??.. just spit balling here but I'm gonna say the vast majority of pcmo's sold are grp2 and 3 based lubes, which aren't particularly known for their solvency (which is good because POE/POA can wreak havoc on some rubbers if not supplemented with SCA's). Hence the need to employ use of a solvent based product to free stuck rings. This is the preferred approach outlined in many OE TSB's in re to stuck rings. Fwiw, i've personally never seen a TSB that instructs the vehicle owner to go out and buy some Amsoil to free stuck rings but hey maybe one exists.... Not saying it doesn't work, just saying it's an outlier approach to solving this problem.

That said... good on Amsoil for solving your stuck rings problem.

 

[Germanium]

Originally Posted by Mad_Hatter
Originally Posted by Germanium
It is false that oil base type can't have remarkable difference in ring sticking.

It's not a demonstrably false statement given what, 99% of commercially available lubes are not majority PAO/POE based lubricants??.. just spit balling here but I'm gonna say the vast majority of pcmo's sold are grp2 and 3 based lubes, which aren't particularly known for their solvency (which is good because POE/POA can wreak havoc on some rubbers if not supplemented with SCA's). Hence the need to employ use of a solvent based product to free stuck rings. This is the preferred approach outlined in many OE TSB's in re to stuck rings. Fwiw, i've personally never seen a TSB that instructs the vehicle owner to go out and buy some Amsoil to free stuck rings but hey maybe one exists.... Not saying it doesn't work, just saying it's an outlier approach to solving this problem.

That said... good on Amsoil for solving your stuck rings problem.


I would like to note that Amsoil has changed their formula over time. At the time of the XS 500 ring sticking amsoil was actually advertised as being mostly diester based with some PAO to combat seal swell typical of diester based oils. Now it appears that Amsoil is mostly based on PAO with a substantial but not advertised ester component most likely diester. PAO based oils need some ester based oil mixed in order to desolve the needed additives as well as combat seal shrinkage. This was over 20 years ago. Ester based component could be as high as 45% in current Amsoil signature series from what I have read from other sources but no one seems to know for sure as Amsoil no longer advertises their ester componant, only the PAO.

Also just because most available oils now use group 2 or 3 base stocks does not mean there still can't be a substantial difference at least in certain areas of importance where the few group 4&5 oils can substantially still outperform group 3 oils though there has been great advances in group 3 as well. It is very hard to beat the solvency characteristics of ester based oils even with the advances in additives for group 3 oils. This is true even without added detergents for ester based oils. Ester based oils still reign supreme in detergency even without additional detergents.

Anouther factor of ester based oils that can have superior performance is the very solid cling they have to the metal surface due to their strongly polar nature. I believe was this property that caused the improved lubricity during the hot start ups on the XS500 engine which being air cooled tend to run very hot if ridden in city traffic a lot which this one was.

One of the reasons for switching to mostly PAO based oils was supposedly superior temperature range but I actually have not seen that spec wise with the Amsoil. Also they claimed better long drain intervals with PAO but then again I don't see that in the specs either as Amsoil has always advertised their best oil as being able to go 25,000 mile or 1 year even when they were mostly ester based. Other factor due to additive package determines drain intervals of the oil. Amsoil at least in their top grade oil is still group 4&5 based & still contains a substantial ester component even if it is no longer the main component.

 

[PimTac]

A particular oil might be good for 20-25,000 miles but will the engine let it run that long?

Would you run that Amsoil 25k in a Turbo GDI motor? I wouldn't.

 

[Germanium]

I might want to add that these ring were not stuck for a long period & as such were easy to unstuck. If they had been stuck for a long period the likelyhood of major engine damage would have necessitated a rebuild.

My current car also has a ring sticking issue due to poor piston design so even though it has 177,000+ miles on it I switched it to Amsoil to prevent ring sticking due to excess carbon buildup in oil control ring area causing rings above it to stick as conventional oils would not drain sufficiently & would get coked & turn to carbon clogging oil control ring the continue to do the same to compression rings causing them to stick in their grooves.

This is a Saturn SL2 1.9 liter DOHC 16 valve engine known to have this issue.

Currently this engine runs like a freshly broke in engine with excellent power & no visible blowby when I disconnect the PCV valve from engine valve cover, not even when revved up suddenly. There is some oil usage but this was common even when these engines were new. Even new these engines would go through about 1 quart every 1500-2000 miles.

The proper way of unsticking the rings on this particular engine according to factory was to poor Marvin Mystery Oil into cylinder through spark plug hole, let sit some time then place rags over spark plug holes & crank engine using rags to absorb MMO that gets blown out spark plug holes. Otherwise one would have to disassemble engine if this didn't work.

My car had this done about 10,000 miles before I bought it & it runs very well, quite impressively actually for the milage it has on it.

 

[kschachn]

Hard not to notice but all three of your posts since joining yesterday have been some kind of promotion of Amsoil. You're just an admirer?

Originally Posted by Germanium
I might want to add that these ring were not stuck for a long period & as such were easy to unstuck. If they had been stuck for a long period the likelyhood of major engine damage would have necessitated a rebuild.

My current car also has a ring sticking issue due to poor piston design so even though it has 177,000+ miles on it I switched it to Amsoil to prevent ring sticking due to excess carbon buildup in oil control ring area causing rings above it to stick as conventional oils would not drain sufficiently & would get coked & turn to carbon clogging oil control ring the continue to do the same to compression rings causing them to stick in their grooves.

This is a Saturn SL2 1.9 liter DOHC 16 valve engine known to have this issue.

Currently this engine runs like a freshly broke in engine with excellent power & no visible blowby when I disconnect the PCV valve from engine valve cover, not even when revved up suddenly. There is some oil usage but this was common even when these engines were new. Even new these engines would go through about 1 quart every 1500-2000 miles.

 

[Germanium]

Originally Posted by kschachn
Hard not to notice but all three of your posts since joining yesterday have been some kind of promotion of Amsoil. You're just an admirer?

Originally Posted by Germanium
I might want to add that these ring were not stuck for a long period & as such were easy to unstuck. If they had been stuck for a long period the likelyhood of major engine damage would have necessitated a rebuild.

My current car also has a ring sticking issue due to poor piston design so even though it has 177,000+ miles on it I switched it to Amsoil to prevent ring sticking due to excess carbon buildup in oil control ring area causing rings above it to stick as conventional oils would not drain sufficiently & would get coked & turn to carbon clogging oil control ring the continue to do the same to compression rings causing them to stick in their grooves.

This is a Saturn SL2 1.9 liter DOHC 16 valve engine known to have this issue.

Currently this engine runs like a freshly broke in engine with excellent power & no visible blowby when I disconnect the PCV valve from engine valve cover, not even when revved up suddenly. There is some oil usage but this was common even when these engines were new. Even new these engines would go through about 1 quart every 1500-2000 miles.



At one time I used to be a dealer so to speak but that was a long time ago. I was actually somewhat disappointed to see them go to PAO as their main base oil but it still tests about the same so no harm no foul & there is likely still enough ester base in it to retain the positive ester properties along with the positive PAO properties. The 2 bases compliment each other cancelling the not so great qualities but retaining the best qualities.

 

[kschachn]

Ahhh I see, that makes a lot of sense considering your posts.

So do you actually know the current base stock composition of the various Amsoil product lines, or are you just speculating? Some of them may use Group III base stocks, correct? Do you know for sure how much ester is used in the various lines?

 

[Germanium]

Originally Posted by kschachn
Ahhh I see, that makes a lot of sense considering your posts.

So do you actually know the current base stock composition of the various types of oil Amsoil sells, or are you just speculating? Some of them may use Group III base stocks, correct? Do you know for sure there is any ester content?


There is definitely some ester in the signature series & I have read it that is may be substantial but getting an exact amount with out advanced testing would be difficult & Amsoil is not telling what it is. PAO require ester in order to mix with the additives as PAO is not a very good solvent whereas Diester is an excellent solvent. Signature series is indeed mostly PAO & is advertised as such.

I know of only one purely ester based oil produced by Amsoil & that is a compressor oil. Amsoil does supposedly make ester based oils for food processing plants where nontoxic lubricants are required but other than the compressor oil I don't see them advertised to the public.

Supposedly the OE oil is group 3 oil but that seems to be hearsay but could be true since Amsoil is so mum anymore about their base stocks