Can oil dilution cause a gasoline engine to rapidly consume oil?

[pwoco]

Will oil dilution cause rapid oil consumption in a gasoline engine?

I have a 2001 Honda CRV. After a head gasket and valve replacement it started using oil FAST, like a quart every 50 miles. The car also smelled strongly of gasoline. It was not using oil or before this head gasket replacement. The car runs perfectly, and compression seems fine (although not tested yet). I ruled out bad rings, because I couldn’t see any reason that rings would suddenly fail overnight. By the way, the quality mechanic that did the head gasket work couldn’t provide a reason for this sudden oil burning. All symptoms pointed to a valve seal problem. The mechanic said the seals were replaced, but I went ahead and replaced the seals anyway. After that, the car is the same, runs great, smells a bit like gasoline, burns oil.

So now my theory is oil dilution. I am doing some simple tests for oil dilution, smelling the dipstick, flaming the dipstick (yes…). I will do a blotter test today, and will have the oil analyzed if it gets to that. The oil seems thin, it does smell a bit like gasoline, it does seem to flame more easily than oil, and it seems to blacken very quickly.

My next step is to replace the fuel pressure regulator and the fuel injectors. But before I waste my time (money is not the object, I’ll spend whatever I need to get this car running), I was wondering if fuel dilution of my oil could cause the engine to burn oil. Most commonly oil dilution will cause you oil level to rise, not fall, but my theory is this… the diluted oil is thinner and therefore getting past the rings, and being burned off. Does this seem plausible?

 

[Propflux01]

You'd have to be dumping a ton of fuel in the engine for it to be using a quart of fluid every 50 miles. There is something else wrong.

 

[WylieCoyote]

Sounds like a broken ring.

 

[joekingcorvette]

Sounds like something went wrong right before, during, or after the head gasket replacement. It doesn't sound good whatever it is. Probably the rings. One quart in 50 miles is a serious oil burning issue.

 

[ripcord]

Did you do the head gasket work yourself? Fuel dilution is the wrong tree to bark up.

If the engine was burning oil at 50 miles to the quart, you'll have a lot of oil in exhaust system and visible smoke. Do you have goo inside the tailpipe?

 

[pwoco]

You'd have to be dumping a ton of fuel in the engine for it to be using a quart of fluid every 50 miles. There is something else wrong.

If I was dumping a ton of fuel in the oil, the level would be rising, it only takes a little to lower oil viscosity.

 

[pwoco]

Did you do the head gasket work yourself? Fuel dilution is the wrong tree to bark up.

If the engine was burning oil at 50 miles to the quart, you'll have a lot of oil in exhaust system and visible smoke. Do you have goo inside the tailpipe?

No a qualified mechanic did the head gasket work. And it was sent out to a qualified shop to be machined. The mechanic was as mystified as I was because the compression was still good, and there is no reason to believe anything would have changed with the cylinders, or rings.

 

[Titan]

I'd think Something has broken in the engine itself.

 

[BigTimeTA]

I suspect the oil control ring might be broken.

 

[Propflux01]

If I was dumping a ton of fuel in the oil, the level would be rising, it only takes a little to lower oil viscosity.

You're not diluting that much fuel into the oil to thin it that much.

 

[Chris142]

The car runs perfectly, and compression seems fine (although not tested yet). I ruled out bad rings, because I couldn’t see any reason that rings would suddenly fail overnight.

Did the engine overheat?

 

[samven]

So your loosing 1 qt/50miles but are you sure you are burning it. As stated above you would be leaving a smoke screen behind at that rate.

 

[kschachn]

So your loosing 1 qt/50miles but are you sure you are burning it. As stated above you would be leaving a smoke screen behind at that rate.

Yeah this whole post is suspect. 1 quart in 50 miles is a severe mechanical issue.

We get this kind of post from new members from time to time, a grand assurance of mechanical suitability but also indicating a corresponding fault that is fundamentally incompatible with the first assumption.

 

[andyd]

What do the plugs look like?

 

[Faawrenchbndr]

Will oil dilution cause rapid oil consumption in a gasoline engine?

I have a 2001 Honda CRV. After a head gasket and valve replacement it started using oil FAST, like a quart every 50 miles. The car also smelled strongly of gasoline. It was not using oil or before this head gasket replacement. The car runs perfectly, and compression seems fine (although not tested yet). I ruled out bad rings, because I couldn’t see any reason that rings would suddenly fail overnight. By the way, the quality mechanic that did the head gasket work couldn’t provide a reason for this sudden oil burning. All symptoms pointed to a valve seal problem. The mechanic said the seals were replaced, but I went ahead and replaced the seals anyway. After that, the car is the same, runs great, smells a bit like gasoline, burns oil.

So now my theory is oil dilution. I am doing some simple tests for oil dilution, smelling the dipstick, flaming the dipstick (yes…). I will do a blotter test today, and will have the oil analyzed if it gets to that. The oil seems thin, it does smell a bit like gasoline, it does seem to flame more easily than oil, and it seems to blacken very quickly.

My next step is to replace the fuel pressure regulator and the fuel injectors. But before I waste my time (money is not the object, I’ll spend whatever I need to get this car running), I was wondering if fuel dilution of my oil could cause the engine to burn oil. Most commonly oil dilution will cause you oil level to rise, not fall, but my theory is this… the diluted oil is thinner and therefore getting past the rings, and being burned off. Does this seem plausible?

Your rings are shot. The valve job increased the compression. It is now showing you that rings are shot. Now your engine is burning an extremely large amount of oil.

Just for ****s and giggles, start the engine and then remove the oil filler cap. You were going to see a choo-choo train.

You should be able to see the cloud. The fuel pressure regulator, and the oil dilution is not the issue.

Save yourself some money and do a compression check. It will confirm the condition of your rings

 

[pwoco]

I'd think Something has broken in the engine itself.

Well that's pretty obvious.

 

[pwoco]

Your rings are shot. The valve job increased the compression. It is now showing you that rings are shot. Now your engine is burning an extremely large amount of oil.

Just for ****s and giggles, start the engine and then remove the oil filler cap. You were going to see a choo-choo train.

You should be able to see the cloud. The fuel pressure regulator, and the oil dilution is not the issue.

Save yourself some money and do a compression check. It will confirm the condition of your rings

I WILL check the compression, but the guy who did the original head gasket did, and the compression was fine. It could be just the oil rings, but burning that much oil you would think the compression rings would have to be shot too.

 

[Faawrenchbndr]

I WILL check the compression, but the guy who did the original head gasket did, and the compression was fine. It could be just the oil rings, but burning that much oil you would think the compression rings would have to be shot too.

There is no way it’s burning that much oil without having worn rings. How many miles?

 

[zray1]

There might be a leak that’s dumping the oil on the road.

Or just a combination of all of the above.

Have you checked the fuel trim numbers ?

 

[warnerwh]

I'm surprised a quality mechanic as you say would be stumped. Did he run tests? Is there a cloud of blue smoke? If a mechanic worked on my car and then it started burning a quart every 50 miles I'd want an explanation.