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1982 Oil in vacuum lines

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Old Sep 9, 2022 | 05:27 PM
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Default 1982 Oil in vacuum lines

So i found oily gunk in my lines to headlights while swapping vacuum filter. One guy on Facebook said it had to be worn piston rings, nothing else.

But i wonder if all the smog n emissions equipment on my 1982 could return oily exhaust back into the air intake?

I Want to try cheaper stuff before rebuilding the engine. Thats planned a couple of years into the future.

So im 99% certain i have leaky valve stem seals. Engine puffs alot of smoke out the back while cold, then clean as a whistle after it warms up a bit. Spark plugs where also oily when i changed them. Every single one. New seals and gaskets have already arrived, now waiting on the spring tool to get in stock.

I have asked my shop about a new PCV valve as well. Heard changing it could and should be a part of preventive maintenance.

The air filters where oily too. Not sure when they where changed last.

Intake oil leak seems visible on the outside. It could be from somewhere else. Valve cover gaskets leak.
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Old Sep 9, 2022 | 07:33 PM
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Two checks I would do. The PVC test is easy. Shake it to hear of the check ball rattles. If it doesn't rattle it's bad. Yes, replacing the PVC is a maintenance item. Used to be part of a typical "tune-up". Next thing to do is a compression check. If a cylinder is low try it again with a shot of oil in the cylinder. If the compression goes up it's the rings, if not it's the valves.

Other possibilities are a leak in the intake manifold gasket or a blocked oil passage.
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Old Sep 10, 2022 | 07:04 AM
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oil in the airfilter is definitely a sign of excessive blow by.
Not at all good.
Agree, run compression test dry. then with a squirt of oil in the cylinder. A fair change in compression would indeed indicate worn cylinders/rings.
Oily plugs, oil in the airfilter, oil in vacuum lines.
I think you should reconsider putting off this engine work for a few years.
Really sounds like the time is now.
Or, park the car until you can afford to repair it correctly.
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Old Sep 10, 2022 | 07:42 AM
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take off oil filler cap while engine is running. a little blow by is normal. if it looks like the exhaust pipe, rings are done. a bunch of engines got ring jobs with cheap cast iron rings that last about 10k miles. i re-ringed a mustang and sold it. 40 years ago when u could buy a 69 for 500 bucks and make money selling it for 1800. he came back a year later with huge blow by. he brought a used engine and i put in for him. but a vette done this way in the 70's or 80's may take 30 years to get a years worth of daily driver miles.
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Old Sep 10, 2022 | 07:46 AM
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The vacuum lines should also have a filter for keeping oils/gas fumes out

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Old Sep 10, 2022 | 08:33 AM
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Clakz,

Never heard of oil in the Vac lines going to the headlights.
Engine vacuum pulls air from the distributor, P.B, auto trans, HVAC, PCV, etc, etc, etc.
The engine also pulls, and that's the key word here, "pulls" vacuum from the headlights. I don't see how oil could migrate forward, against the vacuum.
Doesn't make sense. I have never found oil in the distributor. I have never found oil in the trans modulator, nor any oil under the dash (HVAC). All of those accessories are under vacuum just like the headlights and connected to the engine vacuum.

I think what you found in the lines is from something else. Some other source.
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Old Sep 10, 2022 | 10:08 AM
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one possibility. vacuum tank pulls back when engine s shut off if one way valve is bad. if vacuum is connected to intake in an oily place, like teed to PCV valve it could happen.
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Old Sep 11, 2022 | 01:32 AM
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Have to admit, oil in the vacuum lines does signal sime other troubles.
But oil in the air filter. BIG red flag.
This car is 40 years old. And other than that and the little the OP described. We don't know much.
But certainly sounds like some serious work is indeed needed. Not sounding like a bandaid fix.
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Old Sep 11, 2022 | 04:26 AM
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Originally Posted by derekderek
one possibility. vacuum tank pulls back when engine s shut off if one way valve is bad. if vacuum is connected to intake in an oily place, like teed to PCV valve it could happen.
Yes it was bad. I just replaced the one way splitter for headlight vacuum.
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Old Sep 11, 2022 | 04:35 AM
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Originally Posted by 4-vettes
Have to admit, oil in the vacuum lines does signal sime other troubles.
But oil in the air filter. BIG red flag.
This car is 40 years old. And other than that and the little the OP described. We don't know much.
But certainly sounds like some serious work is indeed needed. Not sounding like a bandaid fix.
EGR reroutes exhaust to air filters as far as i can tell from the manual. The car puffs alot of smoke during startup, then clears up in a couple of minutes. Telltale sign of valve stem seals at minimum.

Shop manual says oily air filters is PCV valve swap as first step.
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Old Sep 11, 2022 | 04:39 AM
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Originally Posted by HeadsU.P.
The engine also pulls, and that's the key word here, "pulls" vacuum from the headlights. I don't see how oil could migrate forward, against the vacuum.
.
The check valve in the vacuum was bad. So air would flow from the intake into the lines going to the vacuum tank and towards the headlights on shut down. Often one of my headlights would rise, and i had to restart the engine to try and suck it down again. Not fun to park with a lazy eye.
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Old Sep 11, 2022 | 04:41 AM
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Originally Posted by Richard454
The vacuum lines should also have a filter for keeping oils/gas fumes out
I swapped them both.

The old filter was so oiled up the spongy filter was just collaped down allowing free flow.
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Old Sep 11, 2022 | 04:49 AM
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Originally Posted by derekderek
take off oil filler cap while engine is running. a little blow by is normal. if it looks like the exhaust pipe, rings are done. a bunch of engines got ring jobs with cheap cast iron rings that last about 10k miles. i re-ringed a mustang and sold it. 40 years ago when u could buy a 69 for 500 bucks and make money selling it for 1800. he came back a year later with huge blow by. he brought a used engine and i put in for him. but a vette done this way in the 70's or 80's may take 30 years to get a years worth of daily driver miles.
But why would the engine need new rings during the 80s?

From what i can tell from Carfax, its a one owner car during its lifespan in the US. Not sure if new owners are registered over there? All new owners in Norway shows up.

The car has been sitting alot, and only has 49k miles. Carfax shows it was kept on the road however, and driven 300 miles a year for almost 10 years 99-07, but still kept emissions checks and tags on. I guess the cold starts where oil jas returnere to the pan does give excessive engine wear.

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Old Sep 11, 2022 | 04:52 AM
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Originally Posted by 4-vettes
I think you should reconsider putting off this engine work for a few years.
Really sounds like the time is now.
Or, park the car until you can afford to repair it correctly.
Its parked for now while waiting on new trailing arms.

Im going to check into it during winter and see if i discover issues.
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Old Sep 11, 2022 | 06:51 AM
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So i started it up now, expecting smoke. Nothing.

There is also no pressure coming from the oil fill cap or the dipstick tube. Literally nothing. No smoke, no air, nothing.

There was also no smoke coming from the exhaust. Started up clean, clear exhaust. After a minute it had a brief foggy exhaust and condensation dripping from each pipe, then clear again.

This might be because last time i used it, i only moved it slightly. Less oil to be burnt in the cylinders perhaps?

It idles at 600rpm, a little rough, but this could be vacuum loss in the TBIs, or emissions equipment. Rock hard gaskets so ive gotten a gasket rebuild kit already.

Im still going to swap out the valve stem seals, already bought them and adjusting valves is not bad to do when you dont know how long ago it was last done.
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Old Sep 11, 2022 | 01:21 PM
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Originally Posted by Clakz
So i started it up now, expecting smoke. Nothing.
This might be because last time i used it, i only moved it slightly. Less oil to be burnt in the cylinders perhaps?
When the valve seals were going bad on my '85 It would take it sitting for a few days before I saw the puff of smoke on startup.

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Old Sep 11, 2022 | 02:52 PM
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Originally Posted by brushmor
When the valve seals were going bad on my '85 It would take it sitting for a few days before I saw the puff of smoke on startup.
Its sat for a week almost now. But ive definetly seen the startup puff so im expecting it to happen again later.
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