Spitting oil through tailpipes.

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Are you sure the header evacs are 100% disconnected?

If they are disconnected, then why not expect this as normal? You have no crankcase evacuation at all anymore, and the crankcase pressure is going to push oil somewhere. If it was OK for oil consumption with the evacs in place, then disconnecting them is like disconnecting a a PCV.

As for oiling restrictions helping, I would not be surprised. It's gotta be pushing a lot of oil into the exhaust for it to not be all burned and for the plugs to look so clean, so pooling, with the crankcase pressure resulting from no evacuation, seems likely. Or a restricted drain back to the pan. Pulling a header would be next on my list, as suggested by others; if it is excess oil pooling in the heads, then I would expect to see more oil residue in the back header tubes.
 
First of all if you are seeing oil drip out of your tailpipes , it is most definitely CONSUMING oil. Your oil level will definitely be dropping, it just depends on you and how vigilant you are in checking it. Even if it's just the exhaust seals (this makes no sense on an inline wedge head) it will still BURN on the way out of the port and through the system. What kind of seals are they? What kind of rings? What gaps? Low tension oil rings? If the exhaust seals are submerged aren't the intakes? I think you need to get somebody with really sharp eyesight to follow you around and watch for smoke 'cuz it will be there. J.Rob
 
My first thoughts are it's common to find oil droplets on the rear of the car. More common if the engine is a performance engine and you don't let it warm up before you back it out of the garage. Strokers may use more oil especially if the rings are narrow and the pistons short. Plus you don't have any evac system and it's a street car. The gist of this all is:
You're over-thinking this and it's fine. Keep an eye on the oil level. Get a functional PCV system on it. Let it warm up fully before you drive it. Not a big deal.
 
Hey Mike. Sorry to see a post of woe. But glad to see you here. I’m with Ramm & moper on this.
Have you kept an eye on the dip sticks oil level consistently?

The only place I can see oil getting out is the exhaust valve seal. But it would have to be a super heavy leak. If everything else is sealed well, that’s the only exit. I’d start with removing the header first to see if it is bathed in oil. Can you remove a spring on the head installed in the car?

I hate mysteries like this. Drives me nuts.
 
There is Venturi vacuum at the exhaust valve,
If the valve is awash with oil, and the valve seal is less than it should be, some exhaust seals seem less than they could be, then oil can suck down the guides.
For whatever stupid reason I didn't use exhaust seals on one race engine, it smoked after a number of miles.
I'd do as mentioned, if there's no oil on the plug, it's gotta be coming in the guide., Pull the header away, and you should see oil. jmo
 
The usual blue viton seals.I plan to check inside collector today.

Thanks guys! Will update tonite.
 
why no PCV? you dont need to run it under the carb plate. And whats the issue with the oil drain back out of the heads? If your exhaust valves are not submerged in oil then there is less chance of them pulling solid oil down past the seals. Umbrella style wont help in that scenario. I see now that there is no drainback under the valve guides on those heads...
 
Yeah - honestly the oil to the top end could be controlled better. But it's nothing I'd worry about.
 
This is weird. Had a buddy follow me around yesterday. Said he did notice a little bit of smoke at my shifts and none he could see at WOT.

We took a nice half hour ride and made a couple passes at the local "spot".

I attached a couple pics of my bumper and a plug pic. That one of the tailpipe extension was damn near dripping. Maybe hard to see but the damn bumper was pretty much a mess. It's not from backing up either. Must be some "vortex" thing going on back there.
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Also, pulled a pipe off today and inside the header collector was DRY. The inlet side of my muffler was a wee bit oily, but not what I'd expect.

Oil level down 1/2 quart.
 
Ironmike said:
The usual blue viton seals.I plan to check inside collector today.

Thanks guys! Will update tonite.
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do you mean the umbrella style stem seals? maybe you need more positive sealing seals, like the ones that attach to the guides. They used to have spring-tensioned teflon stem seals, don't know if they still have them. Have you ever put a vacuum on the ports to see how well they are sealed?
Are you running a windage tray? Do you know, for a fact, how much oil is in the engine? Is it a stock pan?
 
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Collector is dry...............Plug is dry.
How does oil get to the bumper and not leave a trail. I'm gonna go out on a limb and say the oil was in the muffler from the earlier engine, or, maybe it ain't oil. That trail on the bottom of the pipe tip looks awful much like soot, to me.
But you would know cuz I cant feel it between my finger and thumb from here,lol.

As to the Eddies holding oil, I found that out too, and cut some drainage channels in 'em with a die grinder.But I never reinstalled the E-vacs. The PCV was doing a good job. I just have a little 367.
Hey just curious, for your trap speed, what was it at the 1/8th, if I may ask?
 
I wonder if those mufflers were only behind the engine he has now, or if they have been behind another engine before
 
you get all kinds of crap on the bumper as its a low pressure area and can draw in alot of stuff. You need these machine to fit "positive seal" valve seals.....and I see where AJ could cut the drainage ditches now....
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Put a 5W20 Castrol Edge oil in it and see if the issue is gone....
If your already using the positive seal around the valves and the guides are in good shape? the issue will be the oil rings are set loose..
Just my 2 cents
:)
 
If the other side of the engine is the same, dry in the header pipes.... then this oil MUST becoming from else where like a leak at the rear main, valve cover, etc...
 
Well, if you only have breathers on the engine now, the crankcase pressure is going to push oil vapors out and they'll go under the car and out the back. Probably explains the oil on the bumpers. Disconnecting the evacs probably caused that to show up. Yes, the whole back area is a low pressure area.... drive down a dry dirt road and see where the dust collects.

As for the tailpipe, those tips do that all the time! They are forming a low spot where any small amounts of exhaust oil will tend to collect/condense, then drain out along with water vapor and soot from the normal combustion process that naturally collects/condenses there too. If this is your drip out of the tailpipe, then that seems easily explained.

The smoke at the shifts might be from the intake... seals or intake leak: a classic symptom... or is just an over-rich mixture that is 100% normal when any carb is suddenly closed. If it's oil, such small amounts would immediately burn off in the cylinders. No smoke under load should indicate that the rings are sealing well.
 
Looking at the pictures - that's nothing. Run a PCV, or monitor the oil level and wash the car. A lot of that is carbon, BTW.
 
I have had a positive seal look like it was fine but was actually riding the valve up and down. Make sure they are REALLY attached to the guide and just not pretending to. A quick look and you might miss that its up a bit.
 
furrystump said:
I have had a positive seal look like it was fine but was actually riding the valve up and down. Make sure they are REALLY attached to the guide and just not pretending to. A quick look and you might miss that its up a bit.
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Thanks. Will check.
 
The carbon is the soot. The oil is the slick and slimy. Your tailpipes are full of soot. So the condensate warming up, and oil vapor in the gasses pull it up and carry it out. The airflow around the rear of the car at speed sticks it all over the back end.
 
Im with the op though, there has to be oil mixed in with the soot. every once in a while when i crank my car up after its been sitting for 3 weeks or more there is a slight mist of black carbon on the work bench that sits behind my car, and some tiny little drops get on the bumper but not while driving just on start up, deff doesnt look anything like his bumper after driving it regardless on how hard or easy i am on it. Everytime ive had carbon mix with wator vapor it doesnt feel like oil, its slick feeling but doesnt feel like motor oil.

I have some carbon build up around the tip connections and a few other smaller places

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Where it covers the work bench on start up, also realize this build up on the bench is from 5 years worth of starting my car 3ft or less from it.

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The carbon is the soot. The oil is the slick and slimy. Your tailpipes are full of soot. So the condensate warming up, and oil vapor in the gasses pull it up and carry it out. The airflow around the rear of the car at speed sticks it all over the back end.
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Seen that very thing in motorcycles, snomobiles ,quads and many other types of equipment.
 
moper said:
Looking at the pictures - that's nothing. Run a PCV, or monitor the oil level and wash the car. A lot of that is carbon, BTW.
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moper said:
The carbon is the soot. The oil is the slick and slimy. Your tailpipes are full of soot. So the condensate warming up, and oil vapor in the gasses pull it up and carry it out. The airflow around the rear of the car at speed sticks it all over the back end.
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I think Moper nailed it.
At the threads start, it seemed funny. But the insistence it is only oil had me wondering.
My exhaust can produce the same pictures and I know there is no oil leak.
 
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