"condensation" in oil?

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I was in to AZone today, got a Mobil 1 filter and Mobil 1 ext. life synthitic. I was looking at the filter options and buddy at the counter says how long between oil changes, I said about 6 months with this filter/oil. He says I wouldn't and walks away...so I follow up with why? He says condensation, that's it. Didn't want to hear him articulate a response. Could someone explain his possible explanation of condensation? Maybe he was right, but I enjoy hearing the responses here which always are valued and trusted.
 
Your buddy's answer has *some* validity.

IF your car is driven primarily short trips and the oil isn't brought to operating temp, condensation CAN develop and introduce moisture into the oil, which will create acids. If you drive primarily on the highway or around town for long enough to properly warm up, then his answer is not meaningful.
 
Originally Posted By: coopns
Could someone explain his possible explanation of condensation?

Condensation of what? Water? Debris?

Water condensation is not an issue if the engine gets up to temp frequently and stays there long enough to burn off moisture. 6 months is not a problem, even if you are short tripping a lot.
 
If you look at the different UOA's in this forum, water contamination is very rare as it evapourates off. Obviously if you park next to the ocean and only ever do 5 minute trips, then water contamination could be an issue in OCI terms.
For 99% of vehicles 1 year for a time related OCI is fine and 2 years is probably OK if you use a garage at night and a major brand full synthetic.
Dust storms are more of an issue for many engines than condensation in oil life terms.
 
Originally Posted By: RF Overlord
If you drive primarily on the highway or around town for long enough to properly warm up, then his answer is not meaningful.

+1
 
This is where a used oil analysis with TBN (total base number) really gives some answers. The problem with condensation is that it can turn acidic. If your oil still has high TBN after six months, then it is fine. 6 months seems like a reasonable length of time for a daily driver if you want to be frugal with your oil change regime.
 
Originally Posted By: 05foresterXT
This is where a used oil analysis with TBN (total base number) really gives some answers. The problem with condensation is that it can turn acidic. If your oil still has high TBN after six months, then it is fine. 6 months seems like a reasonable length of time for a daily driver if you want to be frugal with your oil change regime.


I have never seen a TBN decline to a significant degree just because of moisture and the 6 month limit from some manufacturers does not seem to have a sound basis. The big TBN sludge forming killer is Glycol or other similar anti freeze compounds.
Most vehicle manufacturers outside the US quote one year, but some oil monitors in new cars are set for a time related base of 2 years (Honda, VW and Audi).
Most water contamination evapourates, so I have a suspition that dust storms that cause deposits around the intake area could be a factor in age related limits, because if you had regular sand or dust devils or storms hit the car, then every time you start a fair amount of ultra fine Silica is sucked in and the real fine particles go through the air filter and past rings or valve guides into the oil. That could easily cause a build up of highly abrasive Silica crystal over time, even if the vehicle was not driven much.
 
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Skyship, you're right condensation won't cause tbn to drop. It's the interaction of gasonline, EO, and metals that cause acidity build up. There is truth to short trips being bad for the car. If the EO doesn't get up to operating temperature the gas that slides past the rings will sit in the oil pan. Over time this will break down the EO and create larger acid values. I'd be more worried about condensation in the gas tank.
 
Originally Posted By: Neenos76
Skyship, you're right condensation won't cause tbn to drop. It's the interaction of gasonline, EO, and metals that cause acidity build up. There is truth to short trips being bad for the car. If the EO doesn't get up to operating temperature the gas that slides past the rings will sit in the oil pan. Over time this will break down the EO and create larger acid values. I'd be more worried about condensation in the gas tank.


Thanks for that, as my background is very diesel orientated and the chemistry involved is very different, as is the fuel quality in the US. The question is why do only a few manufacturers of petrol engines say 6 months, although it's rare to see a 6 month warning for a petrol car sold in the EU. My guess is that US dealers want owners to return more often.
I suppose the important factor with fuel contamination is engine age or condition combined with time at idle, as older engines (Might be worn injectors in many cases)that spend too much time at idle sometimes show fuel contamination, with the old big blocks top of the list.
 
Thats why bitogers are always pushing pcv replacement. Your pcv actually helps remove water vapor before it can condense. Every engine has hot spots and cooler spots. Anytime you heat air and cool it you will get condensation. Thats why we has pcvs and engines are designed to try and keep oil temps around 100 degrees Celsius. To boil off water and fuel. Oils also have additives to combate the acids condensation can cause.


In conclusion I wouldn't worry about it. Just take a highway drive every now and then if your a short tripper.
 
Originally Posted By: Neenos76
Skyship, you're right condensation won't cause tbn to drop. It's the interaction of gasonline, EO, and metals that cause acidity build up. There is truth to short trips being bad for the car. If the EO doesn't get up to operating temperature the gas that slides past the rings will sit in the oil pan. Over time this will break down the EO and create larger acid values. I'd be more worried about condensation in the gas tank.


Condensation is directly linked to tbn drop because water in motor causes acids to form which reduces TBN
 
Has anyone seen a UOA showing water contamination, it's the one contaminant that seems to be missing and even if it emulsified it would still show in a UOA as water. Emulsified oil tends to absorb soot and get caught in the oil filter, modern crankcases are much better sealed, so condensation seems to be much less of a factor.
 
Originally Posted By: skyship
Has anyone seen a UOA showing water contamination, it's the one contaminant that seems to be missing and even if it emulsified it would still show in a UOA as water. Emulsified oil tends to absorb soot and get caught in the oil filter, modern crankcases are much better sealed, so condensation seems to be much less of a factor.

What? Are you aware how condensation forms? Let me explain it for you.
When an engine is hot,and cools down condensation can form on the inside of the oil pan. If an engine is well sealed this makes the condition WORSE because when the engine cools down this condensation cannot evaporate into the air,ridding the crankcase off the water.
Now on the valve cover of most engines there is a tube that connects to the intake of the engine. As the engine runs this tube sucks air out of the motor,so condensation vapour can be removed,as well as any blow by.
That was just a simple break down for ya there sunkship. Now you can take that info and twist it in your usual way.
 
Originally Posted By: skyship
If you look at the different UOA's in this forum, water contamination is very rare as it evapourates off. Obviously if you park next to the ocean and only ever do 5 minute trips, then water contamination could be an issue in OCI terms.
For 99% of vehicles 1 year for a time related OCI is fine and 2 years is probably OK if you use a garage at night and a major brand full synthetic.
Dust storms are more of an issue for many engines than condensation in oil life terms.

What does being parked by the ocean have to do with condensation in the engine?
Originally Posted By: skyship
Has anyone seen a UOA showing water contamination, it's the one contaminant that seems to be missing and even if it emulsified it would still show in a UOA as water. Emulsified oil tends to absorb soot and get caught in the oil filter, modern crankcases are much better sealed, so condensation seems to be much less of a factor.

As per this quote engines are sealed up better now than before (not sure what that means exactly,maybe engines leaked er.......)so unless you are driving INTO the ocean I'm not sure why the engine being sealed has to do with the price of tea in china.
Please enlighten me oh wise one
 
I wonder if this condensation horror story was developed by the Iffy lube places to help justify the 3K mile OCI. I don't even remember a marine diesel that had oil with any signs of water in it (Apart from head gasket failures etc), although I saw a number of gearboxes damaged by emulsified oil and I think the difference is that the box oil stays fairly cool.
 
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