Smoke from PCV breather

CCM

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Any of you guys with PCV breathers instead of the lines returning the ventilated air to the intake tube ever see smoke coming out of them? I just bought an 03 coupe with a 5.0L MMR stroker and after about 10 minutes of idling I get a steady stream of smoke from the driver's side one.
 

Avispa

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You have the PCV valve hooked up on the driver's side valve cover? The factory line to the intake tube is where air goes IN to the crankcase, not out. The PCV valve has metered vacuum on it and draws air through the crankcase to clear out water vapor and any other blow by gases. Until the new block is run in and the rings are fully seated you may have a little bit of blow by.
 

CCM

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What color is the smoke?
could possibly be blow-by.
I guess I would call it white, here's a video of it:

http://www.youtube.com/watch?v=5I9-q0U-oFU&feature=youtu.be

You have the PCV valve hooked up on the driver's side valve cover? The factory line to the intake tube is where air goes IN to the crankcase, not out. The PCV valve has metered vacuum on it and draws air through the crankcase to clear out water vapor and any other blow by gases. Until the new block is run in and the rings are fully seated you may have a little bit of blow by.

There's no valve, just the breather. The engine supposedly already has around 1000 miles on it. I'm thinking of doing a compression test tomorrow since I would imagine the rings should have been seated after that many miles.
 
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Stanger00

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I get white smoke coming out of my breather tank with my Aluminator. I have both valve covers routed to the tank. Told it's normal for a little bit of smoke.

Use YouTube or photo bucket I'm not downloading a file.
 

CCM

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I get white smoke coming out of my breather tank with my Aluminator. I have both valve covers routed to the tank. Told it's normal for a little bit of smoke.

Use YouTube or photo bucket I'm not downloading a file.

How does your amount of smoke compare to the smoke in the video? I uploaded it to YouTube. Also, have you ever checked to see which side the smoke is coming from?
 

itSSlow98

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I had that same amount of smoke out of mine and it was due to bad rings. Shortly after it started i broke a couple ringlands on the drivers side.
 

gabe1530

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I had that same amount of smoke out of mine and it was due to bad rings. Shortly after it started i broke a couple ringlands on the drivers side.

this.
mine started smoking the same exact way but worse. mine was billowing white smoke out of the breathers.
 

Riddick

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I would guess its blow by (oil getting past your rings). Back in my turbo honda days I had the same thing happening and I had cracked all 4 ring lands..... LEAN is MEAN, lol. Did you buy the car with this motor already installed? Whats your set up and who did the tuning on the car? A compression test should get you in the right direction. If it comes in low and you add a little oil to the cylinder and the compression comes up chances are it a ring issue. Goodluck

Also, do you have breathers on both valve covers? If you only have one breather this will cause issues as well.
 
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Brutal Metal

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Why isn't anybody asking him if he has smoke coming out the exhaust? everyone is saying rings are shot... I get some smoke out of mine
 

CCM

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I would guess its blow by (oil getting past your rings). Back in my turbo honda days I had the same thing happening and I had cracked all 4 ring lands..... LEAN is MEAN, lol. Did you buy the car with this motor already installed? Whats your set up and who did the tuning on the car? A compression test should get you in the right direction. If it comes in low and you add a little oil to the cylinder and the compression comes up chances are it a ring issue. Goodluck

Also, do you have breathers on both valve covers? If you only have one breather this will cause issues as well.

Yes, I bought the car like this which makes it even worse. The set up is a 5.0L MMR900 stroker with a 3.4 Whipple running E85. The motor is supposed to only have a thousand or so miles on it. It doesn't start smoking visibly like in the video until it's been idling for about 10 minutes.

I'm told it was originally tuned by RET in California, and then again by the previous owner somewhere in Iowa.

Aside from running lean, what else could cause ring failure with so few miles?


Why isn't anybody asking him if he has smoke coming out the exhaust? everyone is saying rings are shot... I get some smoke out of mine

I'm not getting any smoke of the same color or smell out of the exhaust.
 

Riddick

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Dont get bummed out just yet. We are just telling you what it possibly could be. Compression test and leak down will tell you everything you need to know. Make sure to post your results on here.
 

Avispa

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Dont get bummed out just yet. We are just telling you what it possibly could be. Compression test and leak down will tell you everything you need to know. Make sure to post your results on here.

+1

Hook that PCV valve back up, too, even if you want to keep a breather on one valve cover. Your blower will thank you for it.
 

CCM

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Thanks for the advice guys, I will do a compression test when I get back home. If it is the rings, is it doing damage to the cylinder walls to have the engine running?

And just out of curiosity, do non factory built engines in general tend have a shorter life span ones directly from Ford?
 

Brutal Metal

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Thanks for the advice guys, I will do a compression test when I get back home. If it is the rings, is it doing damage to the cylinder walls to have the engine running?

And just out of curiosity, do non factory built engines in general tend have a shorter life span ones directly from Ford?
I'd simply do a cylinder leakdown test that will tell you if it's the rings, if I was a betting man the outcome is gonna turn out OK in this regard.. I don't think that's the problem...
 

BMR Tech

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Every engine I have ever had, has a little "smoke" coming out of the breathers. My current engine does it worse than the others, but, it makes good power - so I'll run her until she quits. My last N/A engine even did it, and it was an awesome engine! (346 rwhp with stock Mach engine and Cobra Intake Cams)
 

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