What is the best spark plug for carbon fouling?

OK guys, lazy me here. After years, I finally got around to using my cheap borescope (bought it for my house drains). I don't see anything that jumps out at me, but I don't have any experience reading these type of pictures. Maybe carbon or is that oil in the second pic? Engine has about 155,000 miles on it. The cheap camera is too long to bend and look around, but I think I got some good pics?

Also I narrowed the gap on my old plug to .028 yesterday just to see what it would do. Took it out on a 20 mile trip. When I checked it, it already had tiny carbon deposits clogging the gap. Maybe the old Bosch was just a bad spark plug? I put the NKG in there today gapped at about .038 since I now have electronic ignition with a low ohm coil.

Thanks for the help guys!

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I saw it, but then forgot about it, sorry. Thanks for posting. How do I find if my valley pan is leaking?
The reality as I know it is . . . it's probably NOT leaking. There is no pressure there to make it leak, provided the pcv system is working and blowby is normal. Any oil that gets to the bottom of the valley pan is from splash which can get past the camshaft, which should be minimal.

The metal can erode, or eve crack in the middle from harmonic flexing, but still, no real pressure there to push the oil droplets out. Surely, they can coat the bottom of the metal and seep out probably.

There is always the concern that it a failed valley pan can pull oil into the intake ports if it erodes there. To me, the reality is that it would take a LOT of moisture to start the rust initially and more moisture to keep it progressing between the two pieces of clamped metal (intake manifold and cyl head). When such might happen, IF it happened on the bottom of the port, a vacuum leak on that cylinder would happen. Being on the bottom, might not show up with normal sprays of water or carb cleaner, which are applied from the top side.

If you put an aluminum intake against the metal valley pan gasket, with time, the bead in the metal gasket can wear away the aluminum on the manifold, resulting in a compromised sealing area. As the aluminum is softer than the metal. THAT can caused a leak which can be found from the topside of things. Which is why the one year the 440 6bbl intakes were aluminum, that Chrysler and later FelPro had an additional item in those particular gasket kits (I think FelPro put in all of their B/RB kits?) which amounted to the two paper gaskets for contact with the intake manifold side of the valley pan to prevent/greatly lessen such erosion of the aluminum by the metal valley pan gasket. An interface to let things move as the different expansion characteristics of the two metals happened with each hot/cold cycle.

So, IF you perceive you have a valley pan gasket leak, first thing to do is to check the torque for all of the intake manifold bolts. Not a lot of reason for them to get loose or back-off from the initial torque readings, but always check that FIRST.

When torqued, the clamping force is supposed to slightly flatten the beads on the gasket for a good seal, as the metal is softer than the cast iron it is sealing against. That seal is good enough to apparently please the Chrysler engineers as it has been that way since they introduced the RB/B engine in 1958.

I realize that almost every diagnostic tree for oi consumption lists the integrity of the valley pan gasket as a possible cause. Key word, to me, "possible", not "probable", normally.

For "valve jobs" and cyl head surfacing to cause a problem in this area, the heads would have had bo have been sut a good bit or even angle-milled. There are formulas of how much to cut the intake manifold mating surface to compensate for these things. Not normally in the realy of a normal valve job, I suspect.

If an engine builder decides to put a cast aluminum valley pan cover on, then soft intake-only gaskets would be needed. That can put a different dynamic on things, possibly.

I will say that these are what I have observed in my DFW/North Texas region and others in other parts of the world might have seen some different things happen. BTAIM

IF you suspect an intake leak, then get the FelPro gasket set and proceed with changing it. That way, you'll know all is well in that area. Any evidence of oil in the intake ports, near the gasket area, should be obvious, too.

Enjoy!
CBODY67
 
OK guys, lazy me here. After years, I finally got around to using my cheap borescope (bought it for my house drains). I don't see anything that jumps out at me, but I don't have any experience reading these type of pictures. Maybe carbon or is that oil in the second pic? Engine has about 155,000 miles on it. The cheap camera is too long to bend and look around, but I think I got some good pics?

Also I narrowed the gap on my old plug to .028 yesterday just to see what it would do. Took it out on a 20 mile trip. When I checked it, it already had tiny carbon deposits clogging the gap. Maybe the old Bosch was just a bad spark plug? I put the NKG in there today gapped at about .038 since I now have electronic ignition with a low ohm coil.

Thanks for the help guys!

View attachment 664186View attachment 664187
The first place I saw borescopes being used to look inside combustion chambers was on the YouTube channel of "ChrisFix" when he was gauging the effectiveness of combustion chamber "cleaners". Using a borescope as you have. You might check out some of his videos to get an idea of what piston crowns look like, for general reference.

Back in the 1972-74 timeframe, when I was making 290 mile trips (one way) from college to home to college on weekends, I noticed that with each round trip, the '66 Chrysler 383 ran just a bit better at the end than it did at the start. That led me to the conclusion that a really good way to de-carbon an engine was a 300+ mile trip. At that time, the popular and good fuel system cleaner was a quart of Berryman's B-12 cleaner in the gas tank. Some people would put a gallon of diesel to do the same thing. Of course, all of the gas tanks back then were 20-25 gallon capacity. 50:1 two-stroke motor oil, 1oz/5gallons mix rate, might be an alternative?

That "bumpy stuff" on the valve heads and head surfaces is carbon. That's where the items you found on the spark plug were coming from. Going to need MUCH more than a 20 mile run or a treatment with some magic cleaner to get them cooked-out. What's on the piston top looks to be more normal, but probably a little more than normal.

I have run .038"-.040" plug gaps with the stock Chrysler parts on my cars. No problems, even for the occasional WOT use. With .035" gaps, the ignition oscilloscope traces at idle were 8-9KV in height, for example, on the '66 Newport 383 2bbl.

Please keep us posted on how the new NGK plug acts.

CBODY67
 
It was years ago, so I don't remember the specifics, but essentially the bottom of one of hte ports on the valley pan wasn't sealing completely.
Checking for a vacuum leak around hte carb and intake manifold as we'd normally do gave null results.
But one cylinder's port was sucking a little air from the cam valley area, and apparently pulled some oil in with it.

I do not know if that would be obvious upon disassembly inspection.
Or maybe the intake port will be wet with oil?
 
The first place I saw borescopes being used to look inside combustion chambers was on the YouTube channel of "ChrisFix" when he was gauging the effectiveness of combustion chamber "cleaners". Using a borescope as you have. You might check out some of his videos to get an idea of what piston crowns look like, for general reference.

Back in the 1972-74 timeframe, when I was making 290 mile trips (one way) from college to home to college on weekends, I noticed that with each round trip, the '66 Chrysler 383 ran just a bit better at the end than it did at the start. That led me to the conclusion that a really good way to de-carbon an engine was a 300+ mile trip. At that time, the popular and good fuel system cleaner was a quart of Berryman's B-12 cleaner in the gas tank. Some people would put a gallon of diesel to do the same thing. Of course, all of the gas tanks back then were 20-25 gallon capacity. 50:1 two-stroke motor oil, 1oz/5gallons mix rate, might be an alternative?

That "bumpy stuff" on the valve heads and head surfaces is carbon. That's where the items you found on the spark plug were coming from. Going to need MUCH more than a 20 mile run or a treatment with some magic cleaner to get them cooked-out. What's on the piston top looks to be more normal, but probably a little more than normal.

I have run .038"-.040" plug gaps with the stock Chrysler parts on my cars. No problems, even for the occasional WOT use. With .035" gaps, the ignition oscilloscope traces at idle were 8-9KV in height, for example, on the '66 Newport 383 2bbl.

Please keep us posted on how the new NGK plug acts.

CBODY67
Hey man, you're great. I really appreciate everyone replying. 90% of my travels are short under 20 mile round trips, almost none highway, so that probably has something to do with it, but wouldn't all cylinders look like this? The other cylinders look cleaner, not great, but for a 50yr old engine, looks better than #6. So do you think it was a bad spark plug or is there any proof in the pic that there's a bad ring, valve? I did compression gauge, but that was over a decade ago. Compression was not perfect. It was down on most cylinders but still in the OK range. Maybe I'll test it again. Maybe compression changed.
 
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It was years ago, so I don't remember the specifics, but essentially the bottom of one of hte ports on the valley pan wasn't sealing completely.
Checking for a vacuum leak around hte carb and intake manifold as we'd normally do gave null results.
But one cylinder's port was sucking a little air from the cam valley area, and apparently pulled some oil in with it.

I do not know if that would be obvious upon disassembly inspection.
Or maybe the intake port will be wet with oil?
Thanks for the reply! When I get a chance, I'll check it out.
 
I've had good luck with Autolite 86, which is 1 heat range hotter (85 is 'normal').

You could also have a leaking intake/valley pan gasket, and the offending cylinder is sucking oil in.
I've never experienced that, but a buddy has.
What do you disagree with @Bill ?
 
90% of my travels are short under 20 mile round trips, almost none highway, so that probably has something to do with it, but wouldn't all cylinders look l
Italian tune-up:

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Italian Tune Up Explained - Removing Harmful Carbon Deposits

An Italian tune-up is a driving technique that involves driving a car at high speeds and loads to improve engine performance. The term originated in the 1950s when Italian mechanics used this method to remove carbon deposits from sports cars' spark plugs.
 
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