Just put a new head on my 225 - still getting some smoke out of the valve cover breather - It does increase a bit under accell - I would think worn rings perhaps but the exhaust is absolutely clear even under load/throttle.
Wouldn't worn rings give me some smoke out of the exhaust??
PCV valve etc is new - anything else to check??

thanks

Mike

A clogged port or an incorrect gasket blocking the port are the most common reasons I've seen for poor PCV operation. Make sure that the port is pulling a vacuum. My port doesn't work at all due to an incorrect carb mounting gasket.

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1980 Aspen 225 super six

You got it, your compression rings are probably shot. If the oil control rings are still basically working, you will not see smoke. A compression test will verify this diagnosis.

D/W

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If it ain't broke, fix it!

Thanks for the replies - could worn rings show up suddenly? It was more less OK until I tried to drive it home from work one day and had smoke flowing out of the valve breather and a real loss in power - ever since I've had much more smoke than normal -

thanks

Mike

More than likely you had some worn (thin) compression rings that broke. I'm freshening the 383 in my '69 Newport right this very moment for the same reason. With a bazillion miles, upon disassembly, it revealed itself to have 5 out of 8 top rings broken (many for a long time, judging by the cylinder wear and carbon build-up), and one second ring broken (recent), which is when it really got bad. I've seen this quite often in high-mile engines. They exhibit all of the symptoms you have described. Like I said, test it using a compression guage, and you will know "fer sure"...

D/W

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If it ain't broke, fix it!

I am having a similar problem with my Duster. I just had a new cylinder head put on it. Valve guides were shot. It only smokes through the breather when the air conditioner is on and idling. You can take the cap off of the valve cover and smoke comes wafting out. It does'nt burn a drop of oil though.

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82 D150-225/727
02 Dakota-3.9/5 speed
87 GMC C7000-8.2 Detroit Diesel/5+2

...oil rings control oil, compression rings create compression. One can be bad, and the other still good (or better, at least).

D/W

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If it ain't broke, fix it!

when I disassembled my slant this summer for a rebuild job, (I was getting too much blowby, as you are) I noticed that I had no compression rings at all (not a single one in decent shape on all 6 cyls) and 4 outta 6 oil rings where dead... and the damn thing wouldn't smoke thru the ex pipe... as I posted on another topic, if your car has auto tranny, they ain't likely to ex pipe smoking. You should do the comp test, but if you really wanna see smoke thru the ex pipe, accelerate on neutral to ~2500 rpm and drop suddenly the gas pedal...

Juan

How come my car only smokes when the air conditioner is on and in gear idling. Is it dropping the idle speed too low? It only smokes through the exhaust pipe when you let it idle for a while and then suddenly hit the gas. If you let it sit for a while switched off for a while and then crank it back up, it will breath out a light cloud of smoke for a few seconds.

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82 D150-225/727
02 Dakota-3.9/5 speed
87 GMC C7000-8.2 Detroit Diesel/5+2

maybe your valvle stem seals are shot, then the ammount of oil ain't that much, but at idle it won't burn as quick as when you're @ part throttle... so when you idle then accelerate the oil burns and you notice smoke.

maybe it gets worse when the A/C is on cuz the extra load causes the engine to drop rpm even more than usual

The cylinder head on my car is 2 months old and has all new components. Does it take a while for the seals to "break in?"

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82 D150-225/727
02 Dakota-3.9/5 speed
87 GMC C7000-8.2 Detroit Diesel/5+2

negative

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If it ain't broke, fix it!

I dunno if rebuilding only the head on a high mileage engine is recommendable. Like 5 months before I rebuilt my engine, I decided to go cheap and did only the head, shaved it off, ported a li'l (all by myslef) and replaced valvle guides, seals, springs, put some hardened seats, new valvles, etc etc. And I know positively that by the time I had no surface scratch on my cyls. So... when the new head was installed over the old block, my guess is that the increase of compression ratio killed the weak rings and messed up everything. In fact, I had less blowby before rebuilding the head, even with my head gasket blown, then after 10k miles after the head work (I was [-] this close to write head job

jeb, how many miles has your block on it? if it's starting to smoke after working on the head, I tell you, I'll be yanking the whole thing appart and checkin on the rings, etc etc. You may get away with gaskets, main bearings, rings, etc etc. I had to rebore 0.20, threw in new pistons, rods, etc etc etc etc

It's the etc etc etc etc that kills ya...

D/W

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If it ain't broke, fix it!

I have no idea how many miles my block has on it. All I know is that the last head was on long enough to wear the valve guides completely out(two dead cylinders) . The head on it has not been shaved or anything like that. I just went down to NAPA and ordered a head that had been completely rebuilt. The bores looked really good, not a scratch in them. There was just ton of carbon on top of the pistons. I probably lost some compression by cleaning it all off (yep, it was that thick.)

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82 D150-225/727
02 Dakota-3.9/5 speed
87 GMC C7000-8.2 Detroit Diesel/5+2