Sudden Oil Consumption Causes?

[wolfehunter]

Just an update from this previous post.

http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3777897/1


I used Quaker State Defy 5W-20 at last oil change after removing the Peak. My maintenance minder is at 60% and I had to add a full quart this morning. So I am well on the way to adding 2 quarts between oil changes which I would like to figure out why. I checked the PCV valve which I had changed and I am not losing any oil through it as it was dry.

Something had to have happened mechanically to go from never adding oil to suddenly having to add 2 quarts between OCI. Gas mileage seems to have dropped minimally but haven't noticed any "seat of the pants" loss of power. Would a rich condition lead to that much oil consumption? Could I have a stuck ring but thought I would find oil in PCV if that was an issue.

I know that a lot of engines "use" some oil between OCI and this is considered normal but going from zero to 2 quarts is a little much.

 

[shrooms]

For some reason, high mileage Hondas consume oil. I'm in the same boat. But, what I have noticed is that, we need to go thicker. I'm using 10w30 Defy and it has slowed a lot. Still consumes, but much less.

 

[mclasser]

Originally Posted By: shrooms
For some reason, high mileage Hondas consume oil

Almost at 200K and don't have any consumption *knock on wood*

 

[B20z]

Some engines seem to use some oil when switching to a different brand. Complaints seem to stop on the 2nd or 3rd OC with the same brand. How many miles are we talking about over this 1qt usage?

 

[Blueskies123]

I have 180,000 miles on my accord and never had to add a drop of oil between oil changes. The oil level never goes down even with a 7500 OCI.

 

[Joe90_guy]

I'm not a car guy and haven't used a spanner in anger since 1978. However I know oil and can offer the following...

If you're consuming that much oil, and there's no puddle under engine, then it has to be going down the tail pipe: the only question is, how is it getting there? First thing I thought of was a stuck ring; oil ring most likely.

I know you have checked the PVC valve but have you checked your plugs yet? If you are seeing sooty deposits on the tips, that will be evidence that the engine is burning oil.

I'm relatively new to BITOG but I've already made the point on several posts that I am concerned about the high volatility of American engine oils. I don't profess to fully understand things but I have a strong suspicion that under the influence of blow-by, fuel dilution (followed by fuel evaporation), water condensation (followed by evaporation), the most volatile part of the engine oil is entering into the vapour phase, whizzing straight through the PCV valve, into the intake system and then burnt. If I have this right, the process will be transient, circular and self-exacerbating.
My answer, for what it's worth, is to move to a much less volatile oil such as a 20W50 or a 15W40. You might just find this unsticks your ring and fixes the problem.

 

[zach1900]

So you're saying the thinner the oil the more volatile it is?

 

[DeepFriar]

Originally Posted By: Joe90_guy
I'm not a car guy and haven't used a spanner in anger since 1978. First thing I thought of was a stuck ring; oil ring most likely.

I know you have checked the PVC valve but have you checked your plugs yet?.

I'm relatively new to BITOG but I've already made the point on several posts that I am concerned about the high volatility of
My answer, for what it's worth, is to move to a much less volatile oil such as a 20W50 or a 15W40. You might just find this unsticks your ring and fixes the problem.



The Buick in my signature has an engine known for excessive oil consumption due to stuck rings (5.3L, "P" code LM-4). As you observe this has been caused by a poorly designed PCV system. To your concerns about volatility would a long term change to high detergent, low NOACK synthetic solve the problem you describe? I am currently attempting that path to decrease oil consumption.

 

[shrooms]

Originally Posted By: Blueskies123
I have 180,000 miles on my accord and never had to add a drop of oil between oil changes. The oil level never goes down even with a 7500 OCI.


Ok, it's mainly a Civic thing.

 

[wolfehunter]

It has been 3200 miles since oil change so I am on schedule to add another quart before the OCI. Maintenance minder has consistently signified OCI's between 7500 to 8000 miles which I did religiously. And like Blueskies I never had to add oil. Until now. I will check plugs and will definitely be using a thicker grade oil next oil change. I hope not to change brands of oil so hopefully QS Defy comes in 10W-30 or 5W-30.

Any other options to try to unstick a ring if that is in fact an issue? Any "one can wonder" additives or cleaners that would not be harmful to try?

 

[TFB1]

A stuck ring on ONE cylinder should produce noticeable smoke and be some oil on the spark plug of that cylinder... If it's using oil on all cylinders due to worm rings or valve stem seals, probably won't be noticeable smoke but may be a little fluffy carbon on the spark plugs after 10-15K mi...

 

[roadrunner1]

Its more than likely attributed to switching brands of oil, no need to jump to a thicker grade.
In my '14 Escape I have been using QS Ultimate 5w-30 I bought on sale, I have one more change with it and probably won't buy anymore as I'm not really happy with UOA's. I haven't seen any consumption, but its not uncommon to see a jump when switching between brands.

 

[DeepFriar]

Originally Posted By: wolfehunter


Any other options to try to unstick a ring if that is in fact an issue? Any "one can wonder" additives or cleaners that would not be harmful to try?


If it is a stuck ring and a gradual approach is not what you're looking for (I'm trying that first) then GM has a top treatment for direct cylinder insertion from a TSB that can be used.

 

[B20z]

Originally Posted By: wolfehunter
It has been 3200 miles since oil change so I am on schedule to add another quart before the OCI. Maintenance minder has consistently signified OCI's between 7500 to 8000 miles which I did religiously. And like Blueskies I never had to add oil. Until now. I will check plugs and will definitely be using a thicker grade oil next oil change. I hope not to change brands of oil so hopefully QS Defy comes in 10W-30 or 5W-30.

Any other options to try to unstick a ring if that is in fact an issue? Any "one can wonder" additives or cleaners that would not be harmful to try?


I would do several more rounds of Defy in the same weight before coming to any other conclusions. To me, 1qt/3200mi would indicate caution not immediate action (which could cause more issue to develop). Have you checked the valve cover gasket and made sure the underbody is dry?

 

[Joe90_guy]

The answer to your question is complicated...

All things being equal (same KV100, same DI, same VII type, same base oil slate), then yes, the thinner the oil (more specifically, the lower the W rating) the more volatile the oil will be. The reason is you need more light (volatile) base oil and less heavy base oil to get the CCS of the oil on-grade.

There's a second order affect in that the thinner the oil, the more VII you will need for a given KV100. VII has poor CCS properties so to accommodate the extra VII, you need a further shift towards light base oil. Basically, the wider your cross-grade, the more volatile the oil will be.

Typically the more additive you have in an oil, the higher will be the volatility of the final oil.

Then there's base oil properties to take into account. Cheap Group I & II mineral base oils yield the most volatile finished oils. Move to all Group III hydrocracked stocks and volatility goes down. More to 'proper' synthetics (PAOs and esters) and volatility drops a bit more (albeit at huge cost!).

Finally you have what I will call the 'sloppy blending' effect on oil volatility. In theory, all you need for say a US 5W30 is a 2.9 min HTHS and 6600 max CCS-30. This oil will have a volatility of 'x'. However if you blend the same 5W30 with an actual HTHS of 3.2 say and a CCS-30 of 4500 you will get a legitimate oil but one which has a volatility of x + y where y can be very significant.

One very last thing I'll say that when people talk about oil, they invariably talk about the NOACK test. This is a test developed in the 1930s by one Herr Doktor Kurt Noack. It's a very blunt tool for quantifying the volatility of modern oils and gives people a completely misleading idea of how an oil might behave. The oils that have been disappearing from Hondas and Toyotas and Audis all have on-grade Noacks of less that 15%. If that is so, why isn't 85% of the oil staying in the sump???

Hope this helps...

 

[wolfehunter]

Thanks for the input. I will check the plugs and underside of valve cover and report back.

 

[KCJeep]

Defy formula just completely changed so even if you stick with it you are essentially switching oils anyway.

Pennzoil HM is the closest alternative I can think of, Castrol HM is very good as well.

 

[B20z]

Originally Posted By: KCJeep
Defy formula just completely changed so even if you stick with it you are essentially switching oils anyway.

Pennzoil HM is the closest alternative I can think of, Castrol HM is very good as well.


That is a good point. Maybe it's best to try something else unless OP can find the "old" Defy on clearance. Sticking with the same product for a few OCIs is the idea.

 

[stchman]

To the OP:

Did the oil consumption coincide with the switch to QS Defy 5W-20 oil?

If yes, switch back to whatever you were running before.

 

[dlayman]

Originally Posted By: shrooms
Originally Posted By: Blueskies123
I have 180,000 miles on my accord and never had to add a drop of oil between oil changes. The oil level never goes down even with a 7500 OCI.


Ok, it's mainly a Civic thing.



Not on my 05 Civic with just under 300k on the clock. Never need to add a drop at 7500 mile intervals of dino 5W20.