I have a question about oil consumption. Brother's car, 90 Civic 4 door sedan, 337k miles. Started with Mobil 1 5w30 but as the miles piled on he went up in viscosity as the oil consumption increased, finally to Mobil 1 15w-50. Valve seals have been replaced twice, head has never been off, compression is factory spec, car passes Calif smog every time with no adjustments needed, car is maintained by an independent Honda shop with a good rep in the area. When the oil consumption hit a quart to a quart and a half every fill up (300 or so miles) he bought a case of Shell Clean Engine Formula 20w-50 conventional oil (Kragen 2.00/qt) and the oil consumption, after an oil change and a couple of hundred miles, has gone down to about 1 to 1 and a quarter quarts per 1k miles. He is into the second oil change with Shell. The oil is changed every 5k miles. He started with Honda filters but over the years changed to NAPA Gold. The car has no oil leaks, is well maintained, has never smoked, runs well and lives in Southern California where we don't have weather. Any ideas about what is happening.
Oil consumption...
- Thread starter OneEyeJack
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I agree. Your oil consumption could be attributed to the vehicle's age. At over 300K miles, I think your Honda has already proved it's value and worth! IMHO, At present mileage, not sure you could nurse it back to "no oil consumption". Just keep your Civic drinking cheaper oil, fill as needed and hope for 350K. Any car over over 300K deserves a medal in my book.
+1 on age. At 300k, for me that's not oil consumption though I understand your point.
I wonder if he's actually leaking/seeping any; with those miles it would be almost impossible not to. It doesn't take much of that to produce some "consumption".
Example: I have a '91 Ranger with the 3.0 that has a bad rear main seal. It "uses" a quart in about 200 to 300 miles now, and has no blue smoke...just a leak almost anywhere you park it. It doesn't look like much but it is. The seal is scheduled for replacement in a week or so.
I wonder if he's actually leaking/seeping any; with those miles it would be almost impossible not to. It doesn't take much of that to produce some "consumption".
Example: I have a '91 Ranger with the 3.0 that has a bad rear main seal. It "uses" a quart in about 200 to 300 miles now, and has no blue smoke...just a leak almost anywhere you park it. It doesn't look like much but it is. The seal is scheduled for replacement in a week or so.
Seems like a good candidate for a 10W-40 high mileage oil.
Originally Posted By: NateDN10
Seems like a good candidate for a 10W-40 high mileage oil.
If the engine is burning oil with a 20w-50 why would you go back to a 10w-40? Does the label "high mileage" mean that much?
Seems like a good candidate for a 10W-40 high mileage oil.
If the engine is burning oil with a 20w-50 why would you go back to a 10w-40? Does the label "high mileage" mean that much?
If the valve seals are ok, and the compression is good, chances are, there's an explanation for the consumption. Try an MMO soak to clean up the rings like the Saturn guys do. Also, make sure the PCV valve is good.
Have seen Honda's with half that mileage use a fair amount of oil.Took a re-ring to cure.They all ran like a top and burned lots of oil.
Fairly typical of worn out oil control rings. The compression rings are still good which is why it runs well and shows normal compression, but compression rings aren't meant to scrape oil. Unlike old iron-block engines, its probably not a good candidate for a quick-and-dirty re-ring and hone, but you could always try it. If you get the head off and there's not enough ridge to catch a fingernail, it will probably clean up enough to get another 80-100k out of it without a complete overhaul.
Given the age/mileage on that engine, there's always the oil burning issue due to hardened valve stem seals (nothing lasts forever, you know).
But first and foremost: replace PCV valve first.
Q.
But first and foremost: replace PCV valve first.
Q.
ARX or mmo type of treatment as they don't cost a whole lot and will not ruin anything .usually?
The engine shoulda never wore out with syn oil eh?
Originally Posted By: Steve S
The engine shoulda never wore out with syn oil eh?
Notice, the OP said the engine cylinder compression was still at factory spec. Rings, cyl walls, and valve seats must still be in good shape for that to be the case. I don't believe the engine is worn out as much as valve seats or PVC system may be flawed.
The engine shoulda never wore out with syn oil eh?
Notice, the OP said the engine cylinder compression was still at factory spec. Rings, cyl walls, and valve seats must still be in good shape for that to be the case. I don't believe the engine is worn out as much as valve seats or PVC system may be flawed.
I just saw the car tonight. He did an oil change and used up the rest of the Mobil 1 15w-50 and within two tanks of gas the oil consumption is right back up. The Mobil 1 is going to get diluted with the Shell 20w-50 pretty quickly and he will continue with the Shell left in the case. No more Mobil 1 left and he's not going to be using it any more. Looking in the valve cover with a fiber optic video camera you can see that there is no sludge and not too much varnish. Also the car had a leak down test and passed. It appears that the valve seals are good. They have been replaced twice in the past. The pcv valve is recent. The old one looked good but in the spirit of leaving nothing undone it was changed, anyhow. I guess that sometimes in some situations conventional oil is better. During the second tank of gas it went down a quart in 200 miles of steady 65mph freeway commuting.
I think the OP's question was why when he switched to a cheaper conventional oil, his oil consumption went down, not what should I do to lower my oil consumption.
My experience has been that Mobil 1 is a very thin oil and regardless of it being a synthetic, some vehicles experience oil consumption when using it, especially in a high mileage one.
Synthetics are not always the magic elixir people make them out to be.
Wayne
My experience has been that Mobil 1 is a very thin oil and regardless of it being a synthetic, some vehicles experience oil consumption when using it, especially in a high mileage one.
Synthetics are not always the magic elixir people make them out to be.
Wayne
Originally Posted By: rslifkin
If the valve seals are ok, and the compression is good, chances are, there's an explanation for the consumption. Try an MMO soak to clean up the rings like the Saturn guys do. Also, make sure the PCV valve is good.
How long do you guys let the MMO soak? I pulled my plugs and poored in a couple teaspoons of MMO into it and let it soak for a weekend. That enough time? thx
If the valve seals are ok, and the compression is good, chances are, there's an explanation for the consumption. Try an MMO soak to clean up the rings like the Saturn guys do. Also, make sure the PCV valve is good.
How long do you guys let the MMO soak? I pulled my plugs and poored in a couple teaspoons of MMO into it and let it soak for a weekend. That enough time? thx
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