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Discussion Starter #1
I pulled my #1 plug out tonight and I was doing some preliminary checking of fuel adjustment and saw the mess below. This is with a Holley 4160 (vacuum seconday 750).

I'm seeing tons of oil here and the stink of fuel. I know I'm running rich, but I'm not sure where that problem actually lies. The float setting is good, and may even be a bit on the low side. Adjusting the idle mixture doesn't affect vacuum unless I give the idle mixture screws full turns and then I only get fluctuations of less than 1".

I don't know if it means much, other than more proof that I'm running rich, but idle jumps about 250rpm when I pull the vacuum secondary line off.

At least my timing is set properly. The "mark" is exactly where the plug readers say it should be. :D

I'm worried about both the oil control symptom and the fuel issue. Any ideas?? Help. :confused:

 

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Overfueling

I had this once. I didn't insure my car one year, took it out after two years, kept fouling one hole. Spent about two days, figured it out to be a warped body. Draw filed it and ....tada ran fine. Pull your metering block and bowl and check your body with a straight edge. An idea........:)
P.s. Same carb as me.(This is also assuming that all mechanicals are OK, comp.,etc)
 

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The oil burning needs to be addressed before tuning adjustments. Oil in the mixture will screw up the burn rate. Pull all the plugs and see if the rest are like that. while they are out do a compression and leak down test. Might be valve guides which won't show up on either test.
 

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Discussion Starter #5
Ron Slabaugh said:
I agree with Paul. Control the oil first.

Do you have a good baffle in the valve cover where your PCV valve connects?
That's the part that worries me the most. I feel a tear-down a comin'. I'll see what I can dig up for a pressure tester.

I'm using a set of OEM valve covers on the motor. I'll double check my PCV connection to see that I have it on the right port in the valve cover.

Thanks.
 

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this is a brand new engine, isn't it ??? how many miles are on it ??? or maybe hours ???

if it's really really low... have the rings seated ???
 

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Discussion Starter #8
Seattle_Mike said:
"right port on the valve cover"? How many do you have?
I'm using the port on the passenger valve cover. There are two ports on the driver's side. One with a vent on it, the other with a oil filler cap. The passenger side port is the only one I can use easily. If I use the driver's side port(s), the PCV hose interferes with the throttle linkage.




the Flyer said:
this is a brand new engine, isn't it ??? how many miles are on it ??? or maybe hours ???

if it's really really low... have the rings seated ???
This is a newly rebuilt engine, yes. I've probably got 300miles on it by now; 8-12 hours of runtime. Should unseated rings allow this much oil into the combustion chamber? It doesn't smoke when running. The exhaust is pillowy white when running, but a bit on the stinky-rich side.
 

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on the factory vortecs the pcv valve goes in the drivers side valve cover, dont know if the baffleing is different between the two valve covers but would be a place to start looking
 

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Discussion Starter #10
kceb10 said:
on the factory vortecs the pcv valve goes in the drivers side valve cover, dont know if the baffleing is different between the two valve covers but would be a place to start looking
If that turns out to be the case, I'll feel both stupid and relieved. :rolleyes: :) I'll check that when I get home tonight.

Then I'll just have to worry about the fuel system.

Thanks!

Brent
 

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The PCV is a likely culprit. I'd still look at all the plugs and see if it's affecting all of them or just some of them.

I'd like to think your rings are seated by now. what's the story on the engine? Crate, engine shop or home built? Rings? Bore and cross hatch?
 

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Discussion Starter #12
Paul Wright said:
The PCV is a likely culprit. I'd still look at all the plugs and see if it's affecting all of them or just some of them.

I'd like to think your rings are seated by now. what's the story on the engine? Crate, engine shop or home built? Rings? Bore and cross hatch?
Here's the story on the engine. I bought it from a local guy who has a good relationship with a local machine shop who reported having great success from this guy's builds on previous occasions. Not a professional, so there was no guarantee. :rolleyes: I'd like to think my rings are seated by now too.


THIS IS A CHEVY ROLLER 350, 638 4 BOLT MAIN BLOCK, BORED 30 OVER,DECKED .008 TO INSURE PROPER SEALING, FITTED WITH SPEEDPRO FORGED L2256 PISTONS, MOLY RINGS,RESIZED RODS,ZZ4 MODEL ROLLER CAM,474-510 LIFT,208-221 DURA. 112 LOBE CENTERS,CRANE ROLLER LIFTERS,CRANK IS GROUND AND POLISHED 20-20,NEW PUSHRODS,OIL PUMP,SCREEN,KING BEARINGS,DOUBLE ROLLER TIMING SET, ROL GASKET SET,BRASS PLUGS,THE HEADS ARE CASTING # 906 VORTEC 194-150 FRESH 3 ANGLE VALVE JOB AND ANY THING ELSE THEY NEEDED,NEW 600 LIFT SPRINGS ,RETAINERS,LOCKS.
 

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Discussion Starter #13 (Edited)
Well, I checked the valve covers tonight and I found that BOTH valve covers are baffled, so reversing them isn't going to help at all. I knew that solution was going to be too easy; I never get that lucky. :rolleyes:

As Paul indicated, this means I either have a valve guide problem, the oil control rings aren't working properly, or some other mysterios PCV issue.

I'm going to start pulling plugs and see what I see and check the PCV valve while I'm at it.

**Edit

Plug #1 - Oil fouled, fuel soaked
Plug #2 - Not oil soaked, Rich/Sooty but not fuel wet
 

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Discussion Starter #15
DriveWFO said:
You guys have a particular part# for a PCV valve? I just bought one that fits my grommet.
I just used the one from GM, part#11161745, the part that is used in the truck the motor originally came out of.
 

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NovatoriusRex said:
Plug #1 - Oil fouled, fuel soaked
Plug #2 - Not oil soaked, Rich/Sooty but not fuel wet
could you possibly have an internal intake gasket leak on the #1 cylinder that is allowing oil from the lifter valley to be sucked in to that cylinder????:)
 

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NovatoriusRex said:
The exhaust is pillowy white when running, but a bit on the stinky-rich side.

hmmm...this has sorta got me thinking....I know you had an over heating issue in the past...could you possibly have a head gasket issue now? Possibly that is where the oil and the white smoke are coming from....just a thought...I'm just trying to think of places the oil could be coming from...If we assume the rings and guides are good(due to the freshness of your motor), and you already determined the PCV is good them that really only leaves two places the oil could be coming from...the intake gasket or the head gasket...unless I'm missing something:)
 

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There are other oil consumption possibilities for a single cylinder:

  1. Valve seal(s) not installed, not correctly installed, or damaged during installation.
  2. One or more compression rings installed upside-down or broken during assembly.
  3. Gaps in rings lined up
Head gasket is not likely.

Intake gaskets are possible, but typically affect more than one cylinder.

That is why it is necessary to pull/review all the plugs before making any decisions.
 

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Discussion Starter #19 (Edited)
Oh, I've done some more testing...which was rather fun BTW. :D

I ran checked the plugs and ran compression tests on all 8 cylinders this morning. Here are the results:

#1 - 180psi - black, sooty plug, oily :rolleyes: :(
#2 - 190psi - black, sooty plug, no oil :rolleyes: :)
#3 - 190psi - black, sooty plug, no oil :rolleyes: :)
#4 - 175psi - black, sooty plug, no oil :rolleyes: :)
#5 - 180psi - black, sooty plug, no oil :rolleyes: :)
#6 - 180psi - black, sooty plug, no oil :rolleyes: :)
#7 - 180psi - black, sooty plug, no oil :rolleyes: :)
#8 - 180psi - black, sooty plug, no oil :rolleyes: :)

I'm encouraged by how the other plugs look(that they're not oily, not the fact that they're black) and I'm practically giddy that all cylinders have good compression. This leads me to believe that I have a bad valve seal/guide or two on the #1 valves in the head causing oil leakage into the combustion chamber.

I think my next task(s) is to see about having new valve seals/guides installed and find the cause of the carb richness.

What are likely causes of richness not affected by idle mixture adjustments??
  • Vacuum leaks?? Do they cause richness?
  • Bad/blown/leaky power valve?
  • Floats too high (already checked this)
  • ???
Thanks for the help so far. We're almost there. :D

**Edit - One more note, I'm not worried about head gasket or intake gasket leaks due to the fact that cylinder pressures are good and the cooling system holds pressure very well.
 

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Interesting. Pull the drivers side valve cover and look at the seal. It may have popped up.
It's possible to replace the seal without removing the heads.

I wouldn't preclude the possiblity the intake gasket is leaking along the valley edge. That would cause a vacuum leak and oil sucking into 1 cylinder. The coolant port may not be leaking until it gets hot and expands. That would explain the white smoke.
 
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