oil on plugs

nawlins-tim

nawlins-tim

Member
I have a fresh build that is showing oil on the plugs. Its a 400 sbc new pistons and rings. New profiler 195 heads.Right after cam break in ( flat tappet ) I checked a couple plugs and all showed heavy black oil. But I chalked it up to rings not seated. Made my first trip out. Ran it up to 4500 a few times and a couple to 5500. It ran cool and no leaks. Drove to the parts store one day and came home , with hood up I noticed what looked like steam or light smoke from both breathers. At that point I figured I needed a proper PCV system. Checked the oil and looked good .NO WATER. But plugs still oilly. This time I figured the rings needed a hard run in. Ran the snot out of it shifting at 6000 through all gears. Checked oil was down a half a quart.
Leak down shows under 5 percent across all but the one cylinder that I could not reach due to the headers. Still showing light smoke from unpluged pcv and oil on plugs but didnt add oil in at least 100 miles of driving.
Gonna pull the carb to look down the runners for possible leaking intake. Not sure where to go next. Thought I covered the bases on this motor. Had a pro build the bottom end. Hope a re-ring isn't in my future.
What would you do ???
 
As a first few things too check, Id suggest checking the ignition timing and verify TDC, on the timing tab and damper, are marked correctly, and the carbs not running overly rich, thus the float levels need to be checked and set and the fuel pressure should not exceed about 5.5 psi or it may cause the carb to flood and run rich. as an engines plugs will look oil soaked if the timing is retarded or the fuel/air ratios excessively rich,and theres not enough heat to burn off excess oil,
and if it was my car the first thing Id suggest is to drain the current oil and take apart the oil filter and closely examine it for traces of metallic trash,just to get a bit more info on the engines condition.
viewtopic.php?f=54&t=10380&p=42904&hilit=filter+inspection#p42904
then refill the engine with a new oil filter and new 10 w30 oil making darn sure that its not over filled, as it may be serious like a busted ring, but it also could be something vary simple like the oil level was too high.
oil entering the combustion chambers generally enters from loose valve guides with valve stem seals that are not functioning as designed, or loose or improperly sized intake gaskets or from excessive piston too cylinder wall clearance.
since you stated that the short block was PROFESSIONALLY BUILT Id think the overly excessive piston to bore issue is unlikely especially since its leak down test was good.
this tends to make me think the intake gaskets allowing oil from the lifter gallery to enter the intake ports or the heads need to be rebuilt,the next step would be to pull the intake and closely inspect the heads and intake for visual indications of the oils source.
once you've pulled the intake manifold try too take and post a few well lighted detailed pictures of the lifter gallery, intake ports and runners, and clear pictures of the spark plugs,labeled as to cylinder, it should prove useful in diagnosing the oil source
 
Thanks for getting back quickly. I was going to pull the carb then manifold for inspection soon. And actually the first day I took the car out later realized I had 7 lbs of fuel pressure at idle. But since installed a fuel regulator and dialed it down a bit. Which did clean the plugs some. You would have to see it but with the pcv unplugged , the fumes come out with a pulsation to the cylinders fireing. Id like to find a misaligned intake gaSket but I wouldn't expect to have pressure in the valve covers. . And keep in mind the heads are Brand New box stock except for steam holes drilled by a shop. Ill get back soon
.
 
if your seeing a pressure pulse or a significant pressure,in the valve cover theres a very good chance that you have a damaged piston, maybe detonation damage, or a valve hit and busted a piston, or possiably a cracked head or blown head gasket, can you post ALL the cylinders compression test, or even better a leak down test on all cylinders, results?

viewtopic.php?f=87&t=332&p=406#p406
 
What type of oil is the engine now ?
What brand ?
Did you use an oil additive with the flat tappet cam ?

Vavoline VR-1 20W50 Race oil a good choice.
 
are you sure its oil? if the car is running really rich the wet fuel and soot can look somewhat like oil on the plugs when infact its fuel... ive had more than one person come to me with that problem only to find out the combination was pegging the bottom end (10.0) of the wideband when we hooked it up
 
are you getting blue smoke out of the exhaust? if it is oil perhaps the wrong valve stem seals are installed or the right ones were installed incorrectly? i would try to peek down into an intake runner and look for signs of drip down.
 
I will do a thorough compression test this weekend. Or is a leakdown test any better?
As far as the plugs being fuel soaked is a possibility. I haven't hooked up the wide band because I thought I would get a bad reading with excessive oil. I have to figure how to use the innovative motorsport lc-1 and see what thea/f ratio is. But the carb is new and throttle response is fine. No fuel dripping down the carb that I can see. As far as the exhaust. I see a faint light color smoke when I rev hard in idle.
And the type of oil .. I only used Joe Gibbs HR.
 
nawlins-tim said:
I will do a thorough compression test this weekend. Or is a leakdown test any better?
As far as the plugs being fuel soaked is a possibility. I haven't hooked up the wide band because I thought I would get a bad reading with excessive oil. I have to figure how to use the innovative motorsport lc-1 and see what thea/f ratio is. But the carb is new and throttle response is fine. No fuel dripping down the carb that I can see. As far as the exhaust. I see a faint light color smoke when I rev hard in idle.
And the type of oil .. I only used Joe Gibbs HR.
Click to expand...
Leak down is better, you can also listen/see where the air is escaping(intake/exhaust valve, rings/pistons, head gasket/coolant) when there is a problem with that cylinder.
Without the a/f gauge you can set the idle mixture for maximum vacuum.

Is the JoeGibbs HR your using synthetic oil?(i think the hr-3 and hr-4 are) thats bad for the break-in, rings willl not seat/seal with synthetic. Should use dyno oil for break-in if thats not the case.
 
infrared thermometers are a very useful tool to track down issues with tuning, or mal functioning sensors
T504-4254_product.jpg

viewtopic.php?f=50&t=138&p=168&hilit=infrared#p168
viewtopic.php?f=55&t=109


A quick VALVE ADJUSTMENT IF DONE CORRECTLY HAS THE POTENTIAL TO CLEAR MANY ISSUES RELATED TO IMPROPERLY ADJUSTED VALVES AND WHILE IT MAY NOT BE YOUR ISSUE ITS A FAIRLY COMMON SCREW-UP RELATED TO TUNING ISSUES, and If it was my engine Id be verifying clearances, but then if it was my engine I'd have done that several times during the assembly process. and would not have farmed out the assembly, mostly because I rarely trust machine shops to do what they say they will without verifying the work carefully.
A visual inspection tool that easily fits thru a spark plug thread hole is valuable at times
PV618.jpg

GOOGLE PV-618 and PV-636
READ thru BOTH THESE RELATED THREAD's, ON FINDING TDC and related info

viewtopic.php?f=70&t=1015&p=1864&hilit=tabs#p1864

viewtopic.php?f=52&t=966&p=13811#p13811

viewtopic.php?f=87&t=332&p=406#p406
chevfireor.gif


TUNING SKILLS MAY BE VERY USEFUL
viewtopic.php?f=55&t=109&p=44341&hilit=+reading+plugs#p44341

viewtopic.php?f=50&t=383&p=470&hilit=vacuum+gauge#p470

a leak down tester is always a good test tool to have access too
viewtopic.php?f=50&t=41&p=49&hilit=+leak+gauge#p49

SUM-900010-TL.jpg

http://garage.grumpysperformance.com/index.php?threads/no-computer-now-what.13973/#post-71209

http://www.harborfreight.com/cpi/ctaf/d ... mber=93547



vgauge.gif


BTW remember those cheap crappy fuel filters I told you to never use
glassfilter.jpg

well heres where they come in handy, you plug them into the rubber fuel line between the vacuum gauge and the intake plenum where they act like a pulse dampers making the vacuum needle stay a bit more steady and easier to read

http://www.cylinderheadsupply.com/valve-guide-tools-guide-top-cutters.html

http://garage.grumpysperformance.com/index.php?threads/leak-down-test.332/#post-14272

http://garage.grumpysperformance.com/index.php?threads/oil-on-plugs.11044/#post-49058





A MULTI METER AND TIMING LIGHT WILL BE USEFUL
image_12926.jpg

http://www.harborfreight.com/5-in-1-dig ... 98674.html

http://www.summitracing.com/parts/MSD-8991/
timinglite6.jpg
 
Last edited by a moderator:
I am not sold on JG Oils.

Break in with conventional Dino oil.
Vavoline VR-1.
Castrol GTX 10W30 . Use a zinc additive.
Then after 500-1000 miles switch to Castrol Edge Synthetic 10w30.
Titanium fortified.
My plan.
 
mathd said:
nawlins-tim said:
I will do a thorough compression test this weekend. Or is a leakdown test any better?
As far as the plugs being fuel soaked is a possibility. I haven't hooked up the wide band because I thought I would get a bad reading with excessive oil. I have to figure how to use the innovative motorsport lc-1 and see what thea/f ratio is. But the carb is new and throttle response is fine. No fuel dripping down the carb that I can see. As far as the exhaust. I see a faint light color smoke when I rev hard in idle.
And the type of oil .. I only used Joe Gibbs HR.
Click to expand...
Leak down is better, you can also listen/see where the air is escaping(intake/exhaust valve, rings/pistons, head gasket/coolant) when there is a problem with that cylinder.
Without the a/f gauge you can set the idle mixture for maximum vacuum.

Is the JoeGibbs HR your using synthetic oil?(i think the hr-3 and hr-4 are) thats bad for the break-in, rings willl not seat/seal with synthetic. Should use dyno oil for break-in if thats not the case.
Click to expand...
Used "Joe Gibbs" break in first. Broke in the cam and drained it. Before the first outing I put in Joe Gibbs HR 10w30. The HR is not synthetic.
I'm thinking I have more than One issue here giving me trouble. I still didn't bring this up to my machinist yet. I need to bring the plugs to him to look at too. And I'll take a couple pics for Grumpy's crowd also.
And I may be wrong here but I Really dont' think by useing Mr Gibbs oil has anything to do with my blow bye issues. And Guys don't take that in a negative way. I am Only here because i respect Grumpy and his followers .Thanks.
PS I am one phone call away from ordering up a new Long Block from L & L racing engines( but I'll start another thread with engine builder options )
 
Many oils won't allow proper piston ring seating.
I have seen it.
Experienced 1st Hand myself.
 
Ok guys. My intentions were to get a good picture of the my spark plugs' condition but since I hadn't ran the car much when i first started my posting here so I went another route.
First I rented a couple tools from the parts store to help in diagnosing my problems. I got a cooling system pressure tester( looks like a mini bicycle pump ) and a gizmo that detects combustion gasses in the coolant. I know initially I was looking for the reason why I had excessive blow by and oil on my plugs. My mind was going in all directions thus these two tests were easy.
Anyway NO COMBUSTION IN THE COOLANT. And the other test showed a small amount of leak-down In the cooling system. I dont know how much pressure loss is OK but , but within 3-5 mins I saw my pressure drop 2 lbs.
So I figured I would pull my intake and replace it with a Performer RPM that I had collecting dust. ( wasn't the COOL air-gap design but whatever ) First thing I noticed upon first start up was that the carb idle was way under what I had I at before. I needed the idle much higher. Which seems like If I cured a vacuum leak this would have been a likely result.
Forgot to say that I put a little hotter thermostat in also, along with one step hotter spark plug. I started out with a 7 NGK race plug. Just what Profiler suggested. Well I got the idle and timing right but ran out of daylight and wont be able to go for a test run till this coming weekend. see ya soon.
 
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