Cleaning sludgy nissan VQ

[MarcS]

Originally Posted By: UltrafanUK
The only warning from Liqui Moly is for the use of their drive around flush, not their idle use ones. It just recommends that you clean the sump and oil pump intake before use and keep the revs low.

If removing the sump is difficult, a lot of Indy garages just rinse the block through with diesel before using an idle flush. In a bad case like yours it is worth doing a double flush.

If you have an oil leaks, changing to a high detergent full synthetic or using an idle flush can make oil leaks worse, as the sludge and varnish can help old worn or split oil seals or gaskets work (It's called the false oil seal effect). In a bad case it might be best to use an HM oil or even some stop leak as a precaution after flushing.


As i mentioned in the initial post, the pan was dropped and cleaned out during the service. What is a 15 minute oil flush going to clean out that the prescribed LC20 isn't going to remove over the next couple thousand miles? Not trying to be argumentative, I'm just not in a rush and would prefer to play it safe.

 

[jarad248]

Thought on cleaning the ring packs up to further reduce oil consumption....

It is a myth that transmission fluid has more detergent in it that oil. why would anyone think that?
Transmissions are a closed system with nothing coming in to contaminate !!

Diesel oil has a lot of detergent.

You wanna clean your engine out the safe way.? run a light weight oil like castrol edge high mileage 0w20 or 5w20.

Run it for around 500-1500 miles. then change it for whatever you like. castrol edge is the best though.

If you want to use a safe potion try >>stp gumout multi engine
When you have room add 8 to 10 oz.

when it gets dirty change it. Please remember no oil in the world will ever handle acid build up beyond 7500 miles.

 

[UltrafanUK]

Using an idle flush or LC20 are just 2 different ways of cleaning the block, but why complicate things by using a product that has to be added in steps after an intial dose during the OCI.
I had a good look at LC20 and it does seem to be a better version of MMO, as it contains AW additives.

I know a lot of folks that are involved in either oversight or insurance of various Iffylubes in Germany and the UK and none of those companies will allow the use of drive around flush additives due to warranty concerns, as those products have no form of approval and or are not made to any defined standard in terms of additional wear or QA matters (That means the manufacturer can change the mix at will).

Using an idle flush is allowed because it is regarded as a maintenance technique, so if a car has a used car extended warranty it will not be invalidated, although it has to be a listed product and in the EU only Castrol and Liqui Moly make idle flushes that can be used by such Iffylubes. The LM one can even be used by a VW dealer, although they tend to prefer sump off cleans and some use a VW flushing rig that circulates a strong solvent around the block using its own filter and pump. It can also be used to clean an auto transmission out.

The main beef I have about cheap drive around flushes like MMO is that they thin the oil at least one grade and if you do that in an engine that is already using a thin oil like an Xw20, or the engine is causing fuel contamination that is enough to thin the oil, it's bad news, even before you consider the risks of blocking the filter, oil pump intake or an oil feed line to a turbo in particular. The risk to a turbo from thin oil, debris and compromised AW layer (The solvents and detergents in the additive do tend to erode that layer, as do high detergent oils for around the first 1K miles of use) is significant.
Also I've know of a number of VVT or cam phaser unit bearing failures that seemed to be caused by the use of drive around flushes, as like a turbo they are easily damaged by any type of poor lubrication.

So the easy safe way to clean up a sludge monster if you don't want to do a full top and bottom manual clean, is to drop the sump if practical and clean it and the all important oil pump intake to get rid of the worst of the sludge, use a major brand idle flush (Might need to be done twice in a bad case) and then keep the first few OCI's to half normal with a good cleaner oil like M1 0w40 or Shell Ultra and keep an eye out for oil leaks just in case you need to use a stop leak. If the engine had any to start with, it's not a bad idea to switch to using an HM oil after the flush. Maxlife 10w40 and GTX 15w40 are the only ones that are cheap and easy to find in the EU, but there are lots of HM oils available in the US and I think Mobil make the best ones at present.

 

[demarpaint]

Originally Posted By: jarad248

Thought on cleaning the ring packs up to further reduce oil consumption....

It is a myth that transmission fluid has more detergent in it that oil. why would anyone think that?
Transmissions are a closed system with nothing coming in to contaminate !!

Diesel oil has a lot of detergent.

You wanna clean your engine out the safe way.? run a light weight oil like castrol edge high mileage 0w20 or 5w20.

Run it for around 500-1500 miles. then change it for whatever you like. castrol edge is the best though.

If you want to use a safe potion try >>stp gumout multi engine
When you have room add 8 to 10 oz.

when it gets dirty change it. Please remember no oil in the world will ever handle acid build up beyond 7500 miles.


The first I'm hearing of using Castrol Edge 0W20 and 5W20 for 500-1500 miles as an engine cleaner. I have my doubts.
I wouldn't be adding STP or Gumout fuel system cleaners to my oil either. I think either one will do more harm than good.

 

[UltrafanUK]

Originally Posted By: jarad248

Thought on cleaning the ring packs up to further reduce oil consumption....
It is a myth that transmission fluid has more detergent in it that oil. why would anyone think that?
Transmissions are a closed system with nothing coming in to contaminate !!
Diesel oil has a lot of detergent.
You wanna clean your engine out the safe way.? run a light weight oil like castrol edge high mileage 0w20 or 5w20.
Run it for around 500-1500 miles. then change it for whatever you like. castrol edge is the best though.
If you want to use a safe potion try >>stp gumout multi engine When you have room add 8 to 10 oz.
when it gets dirty change it. Please remember no oil in the world will ever handle acid build up beyond 7500 miles.


Umm, err!
If you don't want to do a risky piston soak (A badly worn engine can be very difficult to start after a piston soak, as remjoving the varnish and Carbon deposits around the ring seats reduces compression), just use a major brand idle flush and a real good WOT session or even a full Italian to burn out the Carbon.

Never, ever put tranny or brake fluid in an engine to try and clean it, it might not be compatible with the oil seals or gasket sealants and it can wreck the add pack. They do not contain much if any detergents and using a high detergent additive or oil is not an effective way at removing varnish anyway It's takes far too long!

Only major brand HDEO oils have high detegent levels (More than 3000 ppm of Mg plus Ca), some of the cheaper ones are not good cleaners. One of the Amsoils has 4000 ppm of Ca, but is kind of expensive for a short OCI cleaner.

If you have a badly sludged up engine, it's a real daft idea not to fix the issue ASAP. Doing a series of short OCI's is not a safe option and takes far too long. It's also expensive in oil & filter terms.

If you are doing a few short OCI's to get rid of some minor sludge or varnish, just use the thinnest oil that meets the required API or Acea specs and owners manual SAE group limits.
Using a thick oil will slow down top end oil flow and that slows down the cleaning process.

No idea why you think an oil can't handle acids beyond 7500 miles. My last Twingo OCI was 50K km and no harm was done, although I did flush it as the oil was real black.
Lots of UOA fans get real excited by low TBN/TAN issues, but in most non race engines it does not matter if you make one mistake when extending an OCI, as long as you don't do it again, or decide to become a flushaholic!

 

[UltrafanUK]

Originally Posted By: demarpaint
Originally Posted By: jarad248

Thought on cleaning the ring packs up to further reduce oil consumption....

It is a myth that transmission fluid has more detergent in it that oil. why would anyone think that?
Transmissions are a closed system with nothing coming in to contaminate !!

Diesel oil has a lot of detergent.

You wanna clean your engine out the safe way.? run a light weight oil like castrol edge high mileage 0w20 or 5w20.

Run it for around 500-1500 miles. then change it for whatever you like. castrol edge is the best though.

If you want to use a safe potion try >>stp gumout multi engine
When you have room add 8 to 10 oz.

when it gets dirty change it. Please remember no oil in the world will ever handle acid build up beyond 7500 miles.


The first I'm hearing of using Castrol Edge 0W20 and 5W20 for 500-1500 miles as an engine cleaner. I have my doubts.
I wouldn't be adding STP or Gumout fuel system cleaners to my oil either. I think either one will do more harm than good.


Agreed, It's a waste of money using an expensive 0w20 as a cleaner AND most types of Edge do not have enough detergents to be good cleaner anyway.

No idea why anyone would want to use a fuel additive in the oil or STP thickner for a black death sludge case.
Perhaps it's to kill off an old block!

PS: I'm not a fan of combined oil and fuel additives, as some of the worst snake oils say they can be used in the fuel AND oil. Some even say they can be used in both the engine and gearbox.

 

[Vikas]

Quote:
fast forward another 25k mi and i get a check engine light for low oil pressure and camshaft timing. Dealerhip finds a blown oil gallery gasket (not uncommon) and goes to replace under warranty. Turns out the engine is kinda gross inside an and the gallery is sludgy, as is the cam actuator.
Did everybody just skipped this part where 25K miles have been put on the engine using M1 oil? If that did NOT already clean the engine, how the snake oil remedies is going to clean this engine? It sure looks like the sludge is actively being built for that 25K miles instead being eliminated. My guess would be some coolant is sipping in the engine oil leading to the sludge.

 

[MarcS]

Originally Posted By: Vikas
Quote:
fast forward another 25k mi and i get a check engine light for low oil pressure and camshaft timing. Dealerhip finds a blown oil gallery gasket (not uncommon) and goes to replace under warranty. Turns out the engine is kinda gross inside an and the gallery is sludgy, as is the cam actuator.
Did everybody just skipped this part where 25K miles have been put on the engine using M1 oil? If that did NOT already clean the engine, how the snake oil remedies is going to clean this engine? It sure looks like the sludge is actively being built for that 25K miles instead being eliminated. My guess would be some coolant is sipping in the engine oil leading to the sludge.


There's no evidence to support that. Maybe you're just overestimating the cleaning ability of mobil 1?

 

[demarpaint]

Originally Posted By: MarcS
Originally Posted By: Vikas
Quote:
fast forward another 25k mi and i get a check engine light for low oil pressure and camshaft timing. Dealerhip finds a blown oil gallery gasket (not uncommon) and goes to replace under warranty. Turns out the engine is kinda gross inside an and the gallery is sludgy, as is the cam actuator.
Did everybody just skipped this part where 25K miles have been put on the engine using M1 oil? If that did NOT already clean the engine, how the snake oil remedies is going to clean this engine? It sure looks like the sludge is actively being built for that 25K miles instead being eliminated. My guess would be some coolant is sipping in the engine oil leading to the sludge.


There's no evidence to support that. Maybe you're just overestimating the cleaning ability of mobil 1?


Not only Mobil 1 it could be the cleaning ability of synthetic oil in general is over estimated. I think synthetic oil can do some cleaning, and keep a clean engine clean. Using it as a stand alone cleaner could take a very long time, very long, and the results might be disappointing and not worth the wait.

 

[UltrafanUK]

What do you mean by blown oil gallery gasket, cos if that is what the Iffylube or stealer said, they might have meant HG and HG failures are the main cause of sludge cases when the car has had regular oil and filter jobs with a sensible oil and OCI being used.

Anti freeze reacts with detergents and effectively stops the detergents working and that then results in sludge, as the blowby products (Mostly Carbon) then drop out of suspension and form sludge fairly quickly.

 

[MarcS]

Originally Posted By: UltrafanUK
What do you mean by blown oil gallery gasket, cos if that is what the Iffylube or stealer said, they might have meant HG and HG failures are the main cause of sludge cases when the car has had regular oil and filter jobs with a sensible oil and OCI being used.

Anti freeze reacts with detergents and effectively stops the detergents working and that then results in sludge, as the blowby products (Mostly Carbon) then drop out of suspension and form sludge fairly quickly.


It's a gasket that seals an oil gallery on the rear timing chain cover. Not uncommon on VQs

 

[cronk]

Honestly, being familiar with the Nissan 3.5, the timing cover is likely the most susceptible area for deposits. The block and head/cam areas see quite a bit of oil splash and should stay pretty clean running a good synthetic oil at a reasonable interval.
My wifes Quest 3.5 recently turned 70k miles. I have been running Amsoil 0w40 Euro formula at 7500 mile intervals. I can see the cam and a decent amount of the cylinder head through the oil fill hole, and all appears spotless.
I think the additive you are running should clean up what little sludge is likely left and I would then run a synthetic 0w40 of your choice.

 

[MarcS]

Originally Posted By: cronk
Honestly, being familiar with the Nissan 3.5, the timing cover is likely the most susceptible area for deposits. The block and head/cam areas see quite a bit of oil splash and should stay pretty clean running a good synthetic oil at a reasonable interval.
My wifes Quest 3.5 recently turned 70k miles. I have been running Amsoil 0w40 Euro formula at 7500 mile intervals. I can see the cam and a decent amount of the cylinder head through the oil fill hole, and all appears spotless.
I think the additive you are running should clean up what little sludge is likely left and I would then run a synthetic 0w40 of your choice.


I'm on my 3rd cycle of Mola's recommendation above and I am suspecting this is correct. I've cut open 3 filters so far (every 1000 miles and each of them have had some tiny black carbon flecs deep in the pleats, but otherwise looked pretty good and were nowhere near their holding capacity despite the fact that nissan uses lawnmower-size oil filters. I'm guessing the replacement of the front timing cover and components as well as the pan drop and manual cleaning got the vast majority of crud remaining after my 30k of diligent maintenance. After the next short change interval uses my last jug of cheap conventional, I think it's back to synthetic and standard OCI's. Maybe i've just browsed this board too much, but I might purchase a couple UOA kits and send in the next few oil changes just to see where the engine stands and for my peace of mind.

 

[GRWOil]

Go for gold! drain it, dump in 2 quarts of Valvoline 70wt racing oil, and a gallon of seafoam. Race it around the block and drain it.

More seriously seafoam is pretty good, 3 or 4oz in the crankcase with your oil can help a lot.

 

[Pajero]

Hi MarcS,

Did you ever get your Nissan clean? Just thought I would ask.


Respectfully,

Pajero!

 

[MolaKule]

If you have the various covers off, I would recommend pouring LC20 (from LCD, Inc) on everything and then scraping off anything the LC20 couldn't soften.

This appears to be a case of OCI neglect and running the oil way too long. Nissan engines seem to run hot and shear oil.

My experience with Nissan engines is they do best with 10W30's and Severe service OCI's.

I would also recommend a coolant change and an immediate ATF change.

 

[bbhero]

True that the previous World champion did not do well by this motor. But...




It is an engine design problem in that it has not MUCH oil capacity.... Plus these motors tend to run hot and cut down viscosity quite a bit at times as well. 4 qts and 28/32 of oil does not give much room for tolerance of going "too long". 12k miles and 80% of those miles on open highway driving running on a good quality synthetic oil can be done. But as a rule most people don't have circumstances where they run their cars in that fashion. Like Molacule said... These motors are tough even under "good" circumstances.

 

[BAJA_05]

Would be nice to hear some feedback on how this engine is fairing today.


Dale

 

[benjy]

having just purchased a 28,xxx mile 2011 frontier with the 4.0 VQ engine this interests me, i generally use the 10-30 flavor in PA mobil I EP at this time. never heard of LC20 but good info if needed for sure. my 2001 jetta 200,000 mile 1.8T with only 4.5 qts + 10,000 changes ran well at trade time, i used Amsoil 10-30 when it was advertised as PAO prolly with Ester base oil as well. Ester oils are said to be a great cleaner but quite $$$$ to dump with short changes!!

 

[MarcS]

Been a while, figured i'd post an update as I had a question. Engine is still running strong at 85k mi. I've been using LC20 with whatever big name synthetic 5w30 is discounted, fram ultra filters and usually citgo 93 with FP+ as it's reliably the cheapest in my area. OCI's at around 5000-6000mi with no noticeable consumption. Gets gas mileage in-line with or better than epa and gets driven hard with some regularity. The car has not needed anything but regular maintenance since this thread was last updated.

Mola,was wondering if the recommendations from this thread were still current. LCD has stopped selling its additives by the gallon, which means the price is effectively 50% higher than it was a few years ago. If there is a more current recommendation that is more cost effective (whether an additive or new oil technology), that would be great. If it's still the stuff to use, it's a cost that's only incurred every 3 years or so, so NBD.