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Honda Civic EH 95
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Discussion Starter #1 (Edited)
Smoke from oil dipstick hole

Today, after some aggressive driving, I pulled the engine oil dipstick and lots of smoke came out of it. It stopped after a few seconds.

Is it normal on turbocharged D16 engines, or I have to worry about it?
 

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cracked ringland
uhh.. no.

if he had cracked ringlands then it would be smoking like hell out of the exhaust. for it to be smoking slightly out of the dipstick tube it is more than likely excessive crankcase pressure, especially if it is a stock motor. you have to remember that every motor is built with a certain amount of blow by factory to releave crankcase pressure... as you go up in power, especially turbocharged, your ring gaps need to be larger to be able to release the pressure more effeciently. if it is not released properly it is likely that you will blow out your ring lands.

think about when you take off your 710 cap (oil for those of you that dont get the joke), after you get done driving the car... small amount of smoke comes out.. no big deal.

if you are really worried about it, do a compression test and make sure that you have a way other than factory to releave crankcase pressure. if nothing else, just pull off your PCV valve off your "black box" and plug up the hole on your IM.
 

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Classic Man
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if the motor was really hot, the oil could be "smoking a little" from the heat in the block

if its chuffing smoke out your breather and your dip stick tube then id say u should be worried but a little smoke and vapour is no problem
 

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ej8
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uhh.. no.

if he had cracked ringlands then it would be smoking like hell out of the exhaust. for it to be smoking slightly out of the dipstick tube it is more than likely excessive crankcase pressure, especially if it is a stock motor. you have to remember that every motor is built with a certain amount of blow by factory to releave crankcase pressure... as you go up in power, especially turbocharged, your ring gaps need to be larger to be able to release the pressure more effeciently. if it is not released properly it is likely that you will blow out your ring lands.

think about when you take off your 710 cap (oil for those of you that dont get the joke), after you get done driving the car... small amount of smoke comes out.. no big deal.

if you are really worried about it, do a compression test and make sure that you have a way other than factory to releave crankcase pressure. if nothing else, just pull off your PCV valve off your "black box" and plug up the hole on your IM.
You took the 710 cap joke from me lol. But.its a true.story.

And yea oil burns from heat as along as itd not smoking like a train or blowing smoke out the muffler your fine.
 

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the ring gaps are NOT larger to relieve pressure. it is to allow for heat expansion, which is increased with additional power

actual required gap will differ with brand and material
 

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Discussion Starter #12
The PCV hose and valve cover are vented to atmosphere, so I don't think it's a crankcase pressure issue.
I also don't think it's a worn ringlands, cause there is no smoke comes out the exhaust, and the car runs really well and smooth.

So it leaves us with a oil overheating issue? Is it fine like "xile6" said?
 

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The PCV hose and valve cover are vented to atmosphere, so I don't think it's a crankcase pressure issue.
wrong. when you vent the PCV hose to the atmosphere you have gases collecting in the crankcase until the pressure builds up to greater than atmospheric and the gas then escapes out through the path of least resistance. when you take your dipstick out, the hole becomes that path. try putting the dipstick back and disconnecting the breather hose on the valve cover and if I am not mistaken you will see it smoke like a chimney when the engine is idling.

when you connect the PCV hose to the intake, the vacuum in the manifold sucks out gases without letting pressure in the crankcase build up. when boosting this becomes useless because your manifold has the opposite of vacuum in it.
 

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Discussion Starter #14
Isn't removing PCV valve and keeping the hose open, venting the crankcase?

What do you think is the problem, and how to fix it?
 

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like I said, venting to atmosphere is not the same as venting to a source of vacuum. first diagnose the problem accurately before settling on a solution.

1. do a compression / leakdown test and verify that your rings are fine.
2. once you do that, put the dipstick back and check if your valve cover breather smokes when the engine is idling.
3. if it smokes, connect the PCV hose to the intake and see if the smoking from the VC breather stops.
4. if it does, look into the possibility of running an electrical / mechanical vacuum pump to evacuate the oil sump. I remember reading somewhere that you can use the turbo itself as a vacuum pump.
 

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you said you noticed it after a little "aggressive" driving.

I have the Go-autoworks catch can, with the two big hoses off the valve cover, and a big drain back hose going to where the stock black box was.

Had the hood open when it was on the dyno. The amount of "smoke" coming out of that breather can scared me when it was boosting. It was really blowing out of there, I don't mean smoke was coming out, I mean it was blowing with some force. (I did set up my piston/wall, and ring gap loose enough for 300hp)

The guys at the shop didn't give it a second look. They weren't worried, so neither am I. (my compression is good across all the cylinders)

Sometimes I also notice a little smoke after I pull up to a stoplight, or stop sign, and I can sometimes smell fumes driving down the road. (the other day the sun was just right-I pulled up to a stop light, and there was smoke in the passenger footwell area-I thought I had a electrical fire. Frantic search revealed I needed to seal up a hole in my firewall I had overlooked.)

I wouldn't worry about it, unless you also have other signs, like one cylinders compression is different than all the others.
 

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it isn't just harmless smoking. that blow by hanging around in the crankcase has the potential to contaminate the engine oil necessitating early oil changes. it *can* also blow oil past seals and develop leaks. not to mention increasing windage losses and providing sub optimal ring sealing.

Matt The Acid Beaver had told me that the ideal environment in the crankcase was a slight vacuum and would provide for best ring sealing.
 

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ej8
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it isn't just harmless smoking. that blow by hanging around in the crankcase has the potential to contaminate the engine oil necessitating early oil changes. it *can* also blow oil past seals and develop leaks. not to mention increasing windage losses and providing sub optimal ring sealing.

Matt The Acid Beaver had told me that the ideal environment in the crankcase was a slight vacuum and would provide for best ring sealing.
So we come back to whats the best catchcan/ crank case venting system.
 

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So we come back to whats the best catchcan/ crank case venting system.
heh. true. not to sidetrack the topic but I will be replacing the stock baffle box and check valve with this:

and connecting a belt driven vacuum pump [the stuff that comes with diesel alternators] to it.
http://www.che.iitb.ac.in/online/labfacility/cyclone-separator

I don't want engine vacuum to have anything to do with venting the crankcase but don't want to be dirtying the oil and blowing seals either. personal experience and it was not pleasant watching the VC breather smoke away and the oil pump seal leak.
 

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Matt The Acid Beaver had told me that the ideal environment in the crankcase was a slight vacuum and would provide for best ring sealing.
I totally agree with that. Problem is "easily" getting the vacuum source...

I'm willing to pay the price of my oil contaminating earlier, etc, and just changing it, for the ease of not hooking up a proper vacuum source.
 
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