Smoke coming from breather

[540slant6]

Ok guys, some history. My stock internals 318 blew a head gasket at Mason Dixon show in MD back in June. Still ran but dumped a bunch of milky oil into the motor.

Last month I drained the oil and put on a set of decked 360 heads on it. No other changes to the setup. Put a fresh filter and new 10w30 non synthetic in it. The motor runs great, good temperature and oil pressure.

Only issue is that smoke or steam appears to be coming out of the breather. Not terrible but noticeable. I'm thinking some of the milky oil with the water in it is burning off and exiting through the breather. Any thoughts?

I was going to let the car get warm and change the oil again to see if anything changes. I'm familiar with the open versus closed breather debate but there was no smoke before the head gasket blew.

Any help is much appreciated, thanks fellars.

 

[TrailBeast]

It's probably either rings blowby from the water in the oil, or steam from water pockets settled in the motor.

Only time will tell unless you have compression test to compare from before the head gasket.

 

[540slant6]

Makes sense, I'm going to change the oil today and hope for the best.

 

[Inertia]

Were you to take the V/Covers off when cold,, you'd find them coated with condensation..

This likely would be residual from the head gskt,, and should quit after a few long runs,, and an oil change,,

hopefully you have a PCV,, if not,, condensation will continue,..

cheers

 

[nm9stheham]

Have you examined the smoke to see if it is steam? Hold a cold glass or mirror or glass bottle in the smoke and see if it condenses into water on the glass object.

Hopefully the smoke/steam is residual water and not a crack. BTDT..... you need to do several oil changes in quick succession; warm it up, drive it a mile at most, go back and change oil and filter again. I'd do this at least 3-4 times with cheapo oil, and then finally put in good stuff, and keep changing it a lot for a while. That water is in every passage and only oil flow and time will pull it out.

You certainly have a lot of rust in there, with all that time sitting, so it is hard to say if the cam, cam bearings and lifters and main/rod bearings will survive OK. It is a crapshoot at this point, IMO; I would have torn it all down.

 

[Inertia]

Steam dissappears in a few feet,, smoke lingers and forms a "cloud" or trail..

It's one of the first things taught ticket agents receiving vehicles at the ticket booths,,, ..

saves a lotta frantic/false - "car on fire at Booth 6" calls...

cheers

 

[540slant6]

Good input fellas, the "steam" disapates in less than 12" from the breather. I drained the old oil out tonight and will change with some cheap 30w tomorrow. I'll make the third oil change the good stuff. Thanks guys!

 

[RustyRatRod]

Breather as in valve cover breather or air cleaner as in air cleaner? Either way it might be slap normal.

 

[540slant6]

Sorry, it's the breather in the valve cover.

 

[RustyRatRod]

I call that 100% normal. I guess you don't have the stock breather that attaches to the air cleaner? That's the reason you see smoke, because it is vented right to the atmosphere.

 

[540slant6]

That's correct, I'm only noticing the condition because it wasn't present before. BTW, the bump in compression sounds nasty now!

 

[AJ/FormS]

Why is the PCV not taking care of business? It should be routing those vapors back into the plenum and sending it out the exhaust. That's it's job,and why it was invented.

 

[greenswinger]

A wisp of vapor is normal without a PCV.....I run a PCV just so I don't smell it haha

 

[540slant6]

So I'm revisiting my Duster 318 issue. ...

 

[540slant6]

So I'm dusting off this thread because I definitely have some pressure in the crankcase. My first question is, are my valves fully closing with my decked heads? I.e., should I have used shorter pushrods because I now have decked heads? I have hydraulic valve gear so there is no adjustments to the rocker/push rod relationship. The motor runs really strong but there is pressure in the crankcase. Enough to push tiny spurts of oil out the dipstick tube with the breather plugged. I used .028 head gaskets.

Anyone encounter a push rod length issue with decked heads and hydraulic gear? I.e., valves not fully closing?

 

[nm9stheham]

If the valves were being hung open, then the motor would not run strong as you say, not would it run evenly. The amount that the pistons in the lifters are being compressed (lifter preload) is greater but it sound like they are not bottoming in the lifter bodies. And I can't see where it has anything to do with the pressure in the crankcase; sounds like rings or block or head warpage. No PCV or air cleaner vent?

 

[GeorgeH]

Compression test it or leakdown

 

[540slant6]

Yep, compression test in near future. Worse case scenario, over bore and new KB pistons....

 

[gtsdude]

Do you have a pcv valve? My 340 has a pcv and breather that vents into the air and I get a small amount of blow by but no oil out the dipstick, but I run a deep pan and keep it 1 quart low to keep oil off the crank. A little blow by is normal.

 

[540slant6]

So my PCV is routed to my Eddy 600 CFM. However, I run an open crank breather system,

 

[nm9stheham]

Sounds very much like your PCV is not working at all...... or you have HUGE amounts of blowby. The open breather should be an inlet for air at idle and the PCV should be partly opened to pull the crankcase vapors into the intake. Check to see if the PCV works (or just replace), and that the PCV hose is not blocked to the carb base by hardened oil crud, and that it is hooked to one of the large ports leading under the carb base.

 

[540slant6]

So an easy test would be to check for vacuum pulling from the PCV during idle? Any idea how much vacuum it should pull at idle?

 

[gtsdude]

Depends on your cam and how much initial timing you have,
But a stock 318 should have around 15-20 inches of vacum, give or take, when tuned right.

 

[540slant6]

Great, my 318 has a stock cam so I'll check the vacuum later this week. Thanks gtsdude!

 

[plumkrazee70]

I think there is another piece to this puzzle. It seems your pcv is working, but the breather is open to the atmosphere and not hooked up to the air cleaner, like it should be. See picture.