burning oil

[jon521]

hey i have a 71 521 with an L16. i just recently started driving it 2 weeks ago. It had sat for a long time (not certain how long) with normal driving before i bought it, so smoking was expected. The first day i started driving it, I drove it for awhile out on some country roads, and the blue smoke went away. But a few days ago, i put some seafoam down the carb, and some in the gas tank, just to clean things out. So smoking was expected for the rest of the day and maybe the next a bit. but it has been smoking blue smoke for 4 days after i seafoamed it and i am starting to worry. Am i overreacting or do i have a problem?

[Eagle_Adam]

how much smoke? and have you checked you oil for coolant and coolant for oil?

[jon521]

hardly any smoke at idle, obviously more at rmps go up. while im driving around town i can usually look in my review and see a blue haze, but not a huge cloud. if i have it parked, and i rev it up once, i can usually watch a cloud come out and roll away and dissappear in about 20 seconds. Does that help? As far as i know the oil is fine, what would it look like if i had coolant. its fairly new oil, maybe 200 miles on it. Coolant doesnt look like it has oil either. it was changed when the oil was changed as well. Although it is kind of a rust color but i believe thats just cause it was the first coolant change in years.

[datzenmike]

Old motors with lots of wear benefit from having lots of carbon above the top ring to help seal in compression and oil control. I inherited my dad's '64 slant six when I was a kid. He drove it about two miles to work and back year after year. When I got it I changed the oil, (I later found there was a 1/2" layer of white putty like stuff in the bottom of the oil pan) and drove it long distances and within 6 months it was burning oil and I re ringed it. Not saying the sea foam did this but I might have. Well all you can do is drive it and see if it slowly clears up.

[Wide14u]

the oil would look like chocolate milk

[jon521]

Wide

Mine doesn't look like chocolate milk haha thanks

Mike

Thanks that's good to know. Not saying it doesn't have a lot of wear and is old, because it is, but my truck has 90,000 miles on it. But I will continue to drive it and hope it goes away. It just weird it went away then came back.

[Wide14u]

smell the oil see if there is gas in it

[Spades]

when a car smokes at idle(especially if it doesn't seem to smoke unless it idles for a minute at a stoplight or after parked for a while), it is usually valve guide seals. When it smokes under load or at higher RPM's, it is most often(but not always) oil making its way past the piston rings.

 

Blue smoke is from oil or fuel. white smoke is from coolant.

 

When a car sits, it breaks...stuff that wasn't broken before will break when sitting...cylinders still have air and moisture in them and can get rusty, fuel and gaskets get old. You could have anything from a bad tune up to oil getting past a seal or piston rings...if it has been sitting a while, you will have to narrow it down.

 

How does it run? does it smell rich(like un-burnt fuel)? does it smell like burning oil? Did you put new gas in it? did you change the oil yet? if it is oil, you could always try the "mechanic in a bottle" miracle cure in the oil, and then change the oil with fresh stuff. if it is a gasket leaking oil into the combustion chamber, liquid fixes are no good. I have seen a mineral oil or detergent heavy solution (like ATF) added into the oil to thin it out, and that helps clean the crap off the cylinder walls....idle it with some detergent or mineral oil at operating temperature for a few minutes, put a thin motor oil in(non synthetic, break in oil preferred), the drive it like heck, and sometimes rings can re-seat themselves(if that is the problem).

 

honestly, until you figure out if it is coolant, oil, or fuel making its way into the combustion chamber, you are taking a shot in the dark.

[wayno]

I don't know what seafoam is, but you say you put some in the tank, have you burnt all the fuel in that tank completely out, and filled the tank with fresh fuel?

[albyneau]

when a car smokes at idle(especially if it doesn't seem to smoke unless it idles for a minute at a stoplight or after parked for a while), it is usually valve guide seals. When it smokes under load or at higher RPM's, it is most often(but not always) oil making its way past the piston rings.

 

Blue smoke is from oil or fuel. white smoke is from coolant.

 

When a car sits, it breaks...stuff that wasn't broken before will break when sitting...cylinders still have air and moisture in them and can get rusty, fuel and gaskets get old. You could have anything from a bad tune up to oil getting past a seal or piston rings...if it has been sitting a while, you will have to narrow it down.

 

How does it run? does it smell rich(like un-burnt fuel)? does it smell like burning oil? Did you put new gas in it? did you change the oil yet? if it is oil, you could always try the "mechanic in a bottle" miracle cure in the oil, and then change the oil with fresh stuff. if it is a gasket leaking oil into the combustion chamber, liquid fixes are no good. I have seen a mineral oil or detergent heavy solution (like ATF) added into the oil to thin it out, and that helps clean the crap off the cylinder walls....idle it with some detergent or mineral oil at operating temperature for a few minutes, put a thin motor oil in(non synthetic, break in oil preferred), the drive it like heck, and sometimes rings can re-seat themselves(if that is the problem).

 

honestly, until you figure out if it is coolant, oil, or fuel making its way into the combustion chamber, you are taking a shot in the dark.

 

Ummm... I'm going to have to graciously disagree with you on that one, Spades. Fuel does not make blue smoke~ only oil. Fuel smoke can either be white (grossly excessive fuel flow) or black (mild/moderate excessive flow that's seen enough heat to partially carbonize, but not fully burn). I get your gist~ but break is the wrong word. Bio/chemical reactions occur~ depending on the environment succepted to.

 

As Spade says, put your hand in the tailpipe stream, then smell it~ it will tell you volumes: oil, gas, and coolant will be individually obvious. If it smells/feels humid, but not like any one of the above in particular~ you're running relatively clean-n-clear. Flushing with dedicated products, ATF, or diesel will dissolve petrolium-based buildups, but to do so excessively to "reset the rings" is nothing more than rinsing out all lubricants to the point of gross wear in the name of "scrubbing the cylinders" as the old guys would put it. That will make the ring faces reseat in a very loose definition, but the dramatic conclusion is the ring end gaps have increased as well~ negating any benefit.

 

I do not mean to condemn/dissuade any of these measures~ I have utilized them in the past with good, but focused and limited success. ATF, #2 diesel, WD40, paint thinner, and a proprietary penetrating oil are all in my fave's of non-sealant chemicals in my automotive arsenal.

 

I'm gettin tired here, and I'm sure I'm forgetting something~ but I can count on my buds here to pipe in and "wake me up" so to speak...

 

Scott

[flatcat19]

It's an L16.

Do a compression test if ya can.

Keep an eye on your oil and coolant.

If you gain zero conclusions from that, replace valve seals.

[jon521]

i do not believe its coolant or water, its not white smoke, its more kind of a blue smoke. i do not believe it is fuel either, my oil does not smell like fuel nor is the level going up. my oil level is actually going down, but i have a small oil leak. I am not sure what the exhaust out put smells like, i will have to check next time, and i will keep track of what the smoke looks and smells like more and will update. i will look into doing a compression test. Thank you all for your advice, defenetly will help!

[flatcat19]

Valve seals homey.

[king bee66]

i had the same symptoms when my pcv valve busted open

[jon521]

i had the same symptoms when my pcv valve busted open

 

 

may be a stupid question but.....where is my pcv valve?

[jon521]

Valve seals homey.

 

 

i thought if my valve seals were bad, it would only smoke on start up?

[flatcat19]

i thought if my valve seals were bad, it would only smoke on start up?

 

Mine used to smoke really bad, during spirited driving.

Replaced valve seals. None no more.

 

Have you done a compression test?

Do you have access to a leak-down tester?

[king bee66]

may be a stupid question but.....where is my pcv valve?

 

pcv = positive crankcase ventilation, it relieves crankcase pressure. the valve is located on your intake mani and has a hose that runs to the back of the block. it is suppose to seal when you hit the throttle but when its broken open- like on my car, it spits oil into the intake manifold and can billow smoke out the tailpipe.

[jon521]

Mine used to smoke really bad, during spirited driving.

Replaced valve seals. None no more.

 

Have you done a compression test?

Do you have access to a leak-down tester?

 

i will defenetly look into doing valve seals. i have not done the compression test yet, not sure if i have the stuff to do it, my brother might. and i do not have access to a leak-down tester.

[jon521]

pcv = positive crankcase ventilation, it relieves crankcase pressure. the valve is located on your intake mani and has a hose that runs to the back of the block. it is suppose to seal when you hit the throttle but when its broken open- like on my car, it spits oil into the intake manifold and can billow smoke out the tailpipe.

 

 

i do not believe i have a pcv valve.....or is this it?

Edited June 28, 2011 by jon521

[Spades]

Ummm... I'm going to have to graciously disagree with you on that one, Spades. Fuel does not make blue smoke~ only oil. Fuel smoke can either be white (grossly excessive fuel flow) or black (mild/moderate excessive flow that's seen enough heat to partially carbonize, but not fully burn). I get your gist~ but break is the wrong word. Bio/chemical reactions occur~ depending on the environment succepted to.

Scott

 

sorry, did not get a ton of sleep last night...you are correct. black, not blue. it takes a ton of fuel to create white smoke, like a stuck float on a carb, or an open injector/stuck FPR on a fuel injected motor.

 

You would smell the fuel if it was running rich, but blue smoke is most likely oil.

 

one of the symptoms people were asking you about is if the oil level was going up...that happens if the mechanical fuel pump diaphragm goes bad, and oil and fuel meet. You would see oil level go up and it would smell like gas, which is not one of your symptoms.

 

As far as chemical agents, I am not a fan of the mechanic in a bottle fixes...if there is oil making its way past something, that problem needs fixed...sure you can put additives in the gas or oil, but you will need plenty of luck, and as Scott mentioned, the "flushes" can cause more harm than good...I have seen some people do it with some success, but how much harm will be done, well, that remains to be seen. Most of the old timers I have met that swear by kerosene, mineral oils, or ATF to help fix ring issues are from the days when motors needed rebuilt every 50k miles or less.

 

I do not know the L-series well enough to know if it has a PCV valve, look around the engine block for hoses going to the air intake area.

 

Like I said earlier, if it smokes after it has been parked for a while but seems to smoke less or stop smoking after you have had it at RPM's above idle, that is the sign of valve guide seals. Valve guide seals keep oil from leaking into the combustion chamber from around the valves, so as the motor sits(parked not running), oil will slip past the seals. When you run the motor above idle, it burns off the excess oil in the chambers, and unless it is a very bad valve guide seal leak, the smoke should be much less when driving than it is sitting at idle or on start up.

 

A compression test will help you tell if there is a ring or valve issue, but may not tell you if the valve guide seals are leaking slightly. When you do the compression test, if your dry compression numbers are low do a wet test as well...that will help you determine rings from valve issues.

[datzenmike]

PCV valves were in use around '62 in N America. I think it very likely they are still being used to reduce crankcase emissions escaping into the environment.

[jon521]

Like I said earlier, if it smokes after it has been parked for a while but seems to smoke less or stop smoking after you have had it at RPM's above idle, that is the sign of valve guide seals. Valve guide seals keep oil from leaking into the combustion chamber from around the valves, so as the motor sits(parked not running), oil will slip past the seals. When you run the motor above idle, it burns off the excess oil in the chambers, and unless it is a very bad valve guide seal leak, the smoke should be much less when driving than it is sitting at idle or on start up.

 

i get more smoke when i bring the rpms up and hardly any at idle, i do not believe it is a valve guide seal

[Elkie]

The burning of crankcase vapors is a necessary evil as the pcv requires vacuum to function properly. Think of your crankcase as a paint booth, you can use it without any airflow, but if its already got a ventilation system installed why not use it?

 

+1 on valve seals, if its been sitting they can get dry and they crack, letting oil through. If oils getting past the rings I think you would be having other problems as well.

[jon521]

I see. My valve cover vent is running to the clean side of my air filter, but my case breather, is plugged. Your saying it would be better to open it up? I no longer have a pcv valve.