Smoking out of valve cover breather. Update: Compression Sux

[Marty van den Bosch]

For the past week, steady smoke has been coming out of my little filter on the valve cover (no catch can setup) fairly steady - this is a new thing.
Oil is also coming out of the oil filler cap and out of the little filter - this is new in the amount that now comes out (filter always leaked a minute amount).

What I have done since the problem appeared.
Replaced PCV (it was fine however)
Replaced oil and filter (oil was black but clean)
Did my winter rad fluid change.
Checked plugs  they looked great.
No smoke out of the exhaust
Car idles rough but ok (as it has for a long time - not new).

I was thinking maybe rings but smoke does not come out of the exhaust - just the crankcase.

Oil pressure on the lame-o oem gauge is higher than usual but it is well within the "normal" range.

No oil/coolant cross contamination seen when fluid was changed.

The car does not seem as powerful - but the boost is back down to 17, all my stereo equipment is back in (3000 w/ driver now) and I have new tires/ wheels - so this is hard to judge if this is indicative.

At this stage I have no idea.

Perhaps oil is not easily draining back to the pan?
Perhaps MCC time?
Perhaps a compression test?

Anyone have suggestions?

[Chris Andrews]

I'd do a compression test/leakdown test.

[Kimyee Lai]

Sounds like you're pressurizing your crank case...I'd definately start with a compression/leak down test, as suggested.

[Marty van den Bosch]

Thanks guys

[Mike Schmid]

I third that notion.  Really when we're tuning these cars up and looking for all the power we can get out of them we really should be doing comp/leakdowns on a regular basis, at least with every oil change anyways.  That way you'd have a good documentation of the life and times of you motor and a good early indication of its eventual downward trend so you could prepare for its demise.

I have to buy a leakdown tester one of these days...  :roll:

[Kevin Standeven]

yeah mike, I'm still waiting for you to buy one so I can come over and use it  
I won't deny my cheap-bastardness.

Let me know where you went/how much it cost if you get a leakdown test Marty, I could use one too.

[Marty van den Bosch]

And the results are in....


120.135.90.135  :banana


Leakdown was actually not bad however....

None the less - Winter project time  :wink:

[Matt Feist]

What would cause those numbers?

[Martin Raska]

Or more to the point, what did the leakdown tell you as far as where the leaks were?

[Marty van den Bosch]

Many things can cause low compression.

-A 1G Turbo should be 155~165ish with no more than 12psi variance and should be serviced if at 120 or lower

The symptoms tied to the low compression and the location of lost compression (leak down) help to give a better idea.
I did it at lunch with Jordan - never really checked where.

Last time I did a comp/leakdown at LR last December I was 130/140/125/140 and leaking out the exhuast on the leakdown - I am sure it is the same - just alot worse - especially on #3  :wink:

Smoke came out of the valve cover when doing #3 (go figure)

Whatever it is however, opening it up is my next step. It will help narrow it down.

Likely new pistons (landings), rings and a hone will take care of whatever it is.

Next question is what to do - fix ($1500) upgrade/fix ($2000), stroke ($3000), do it right ($6000)

[Jeremy Clarke]

Could smoke out the cover due to a leaky valve seal and a badly cracked guide?

[Mike Schmid]

What do ya mean you didn't listen to where it was leaking?  :roll:  :laugh:  The whole point of the leakdown is to determine what's wrong with the cylinder.  Did you do a dry and wet or just dry compression test?

If you've got 90 psi in the one hole you've got problems anyways.  Possible burnt valves or valve seals if you're leaking out the exhaust and the rings and ring lands are probably beat up pretty bad.  Like you said though the only way to really know for sure is to pull it apart.

Could be worse though, out in Alberta I got to see a 12 cylinder ~7400 cid motor that someone forgot to tighten a crankshaft counter weight on.  The $80,000 bed (oil pan and support structure for the stationary motor) had a big chunk missing and there was a hole in the $180,000 engine block the size of a steering wheel.   :shock:

[Jordan Gladman]

I would put my money on the pistons.

When we performed the compression test on the #3 cylinder, puffs of smoke shot from the valve cover breather every revolution.

If it was intake or exhaust valves, the lost compression would be leaking into the intake or exhaust manifolds. Its compressing the crankcase quickly and with lots of air.. im predicting a cracked piston... 29psi can do some pretty hardcore damage to a cast aluminum piston.  :twisted:

If it was my car, id throw in a JDM and be done with it. I definately wouldnt dump another 6 grand into a FWD that already runs 12.0's ... thats just me  :wink:

[Mike Schmid]

Oops, missed that, ya in that case you've got some piston problems.

[Aaron Moore]

"Do it right..."

Buy an AWD and start swapping :wink: