Help please, plug reading wizards!

-
halfafish

halfafish

Damn those rabbits, and their holes!
FABO Gold Member
Joined
Aug 14, 2016
Messages
4,005
Reaction score
4,529
Location
SW Washington
I'm trying to solve several mysteries with the engine in my truck. It's a standard bottom end .030 over slant in an 82 D150. Originally it was a hydraulic cam motor but I changed it to solid lifters. It has a OCG 2106R cam, pocket ported head, oversize valves (1.70/1.45) a Clifford 4-bbl intake, Clifford shorty headers, and an Edelbrock AVS2 500 carb. I set the carb idle mixture per the instructions but clearly something isn't right. Sadly, I am the goon that assembled this engine and it was my first motor rebuild. Surprisingly, it started right up and runs pretty well. I did have to fiddle with the carb and timing a lot but it runs well and has good power for a small motor in a heavy truck. I have about 700 miles on it so far.

That's the good news. The bad news is, I have a strong ticking noise I will address in another thread.

For today, I'm wondering WTF is going on with my plugs. I changed the oil and all the filters/fluids and wanted to check the plugs. Ick. They look a mess, and I have no idea why. It sure looks like it's running pig rich. The plugs are all heavily sooty and black. There are more issues, though. The #1 plug is an odd color - a really grey instead of the normal shiny chrome color on the metal body. The #4 and #6 plugs are horribly fouled. #4 has what looks like oil all over it, and #6 has what looks like oily buildup all over the threads. The rest of the plugs are less crappy looking, but none of them look good. #4&6 have a clear brown ring about 1/4" up into the ceramic part of the body.

For a truck that runs well, what the hell is going on? I know I need to figure out the ticking/rattling, and figure out why my plugs are a disaster. All thoughts and ideas are welcome here.

DSCN1252.JPG


DSCN1251.JPG


And a closeup of #4 and #6

DSCN1250.JPG
 
Well Zach, what are we readin here? Idling in the driveway? What? You cannot just yank plugs and get a good read on them any time. There is a procedure. Which procedure did you use?
 
The same engine in my Duster, when I pulled it outta my Sat, had nice looking plugs, changed over, only difference was, electronic ig, new plugs, and a " buddy " adjusted the idle air.. doubt this is applicable info. But, the only similarities is the fact, after rebuildn the front end, and battling distributor issues, had a Lot of " driveway" time. Personally, I'd listen to RustyRatRod....
 
Time to step back and relax a bit.

#1 plug body discoloring is nothing more than the plating not being on that plug. Have cleaned plugs in Mirotic Acid and it will eat the zinc plating off like that. Want to take a temp gun and make sure that cylinder is not running hot for some reason.

On first start up with your fresh engine, performance cam, timing could have been off and too rich of carb jetting, not to mention the assembly lubes you have to burn out of it.

Doing lots of carb adjustments and jetting at first to get the fuel air mixture right at idle speeds is a good way to foul the plugs right off the bat with your performance cam.

Most people put too big of cam in their builds, so that creates a lot of valve overlap at idle. Both valves open at the same time not burning fuel air properly.

Need to get them up over 2000 rpm so the cam and valve timing comes into it's performance operating rpm range. This is where the plugs will start burning cleaner.

Now that you have it broke in, things adjusted and some miles on it. Good time to put in a fresh set of plugs, take it out and run it up over 2000 rpm for at least a half hour.

Bring it back in, shut down right away without sitting there idling. Take a read on your plugs. I am sure you will see a big improvement.

Now this is the point where you go back over the fine tuning. Considering if your ignition and coil is up to task for hotter spark, advance ignition timing . . where is it set 12° - 20° ???

Reset your mechanical valve train valve lash adjustment.

Run non Ethanol fuel.

Compression, Fuel, Ignition
The 3 things that make them run nice.

Process of Elimination. I like to swap on a different carb, borrow from a friend. See if that makes it better or worse.

1406 Edelbrock is a good all around carb that works well for a variety of engines right out of the box. Might be a little much for your 6, but good for a test. Might work well on it's own, never know till you try.

Good Luck

Screenshot_20210709-203633_Gallery.jpg
 
#1 looks to me like it is over-heating. Since in the beginning there is some inconsistencies in the readings ,I would try another brand of plug and see if that continues.
 
Zach, I was lazy earlier. Big surprise. But here's how "I" read plugs.

Get the engine warmed up fully. Go drive it around some and get some heat soak in it. Now, do this as close to your drive way parking spot as possible.

Give a wide open blast into high gear. Back out of the gas and kill the ignition at the same time. Be careful not to lock the steering wheel if it's a column ignition. lol

Coast into your driveway parking spot and THEN read the plugs. Otherwise, all you're doing is reading "what the car did last", which might be idling in the driveway and you'll always get a rich reading like that.

That's my method and it's worked well for me. I'm sure others will be along to blast me and disagree.
 
Blast,.Blast.... yeah right.. .I don't know much, but I have read, that's how you do it. At the end of a WOT run, off the gas, ignition killed.
 
I would think the UR4 heat range is a little hot (well, a lot really judging by the glazing) for starters. I'd swap in something compatible in the 5 series and then do the plug reading procedure presented by rusty.
 
A little more info, to start. To break in the engine I did the initial on a run stand at a friend's house. Once it was in the truck I got it running and drove it politely for the first 100 miles or so, at varying speeds. After that I did the occasional harder acceleration as I got more miles on it. It hasn't been driven super hard but it's not been babied for the current 700 miles.

The ignition is the HEI conversion, I forgot to mention that earlier. The distributor is a Super Six with a fresh rebuild.

RustyRatRod said:
Well Zach, what are we readin here? Idling in the driveway? What? You cannot just yank plugs and get a good read on them any time. There is a procedure. Which procedure did you use?
Click to expand...

I'm such a newb at diagnosis, I had no procedure at all. I parked the truck from its last grocery store run and pulled the plugs a week later. I saw your process in your later post, I'll give that a try.

George Jets said:
Want to take a temp gun and make sure that cylinder is not running hot for some reason.
Click to expand...

I have a temp gun and will give this a shot.

George Jets said:
On first start up with your fresh engine, performance cam, timing could have been off and too rich of carb jetting, not to mention the assembly lubes you have to burn out of it.
Click to expand...

Yes, timing was all over the place while I fiddled with it. It doesn't help that my two best local resources, both very experienced slanters, disagree on ported or manifold vacuum. I tried them both but I don't know which was better. I currently have it on manifold vacuum and set at about 18* initial. I do not get any pinging under heavy load.

George Jets said:
Most people put too big of cam in their builds, so that creates a lot of valve overlap at idle.
Click to expand...

The cam isn't all that much bigger than stock, it's more of an RV cam for better low end grunt.

George Jets said:
Good time to put in a fresh set of plugs, take it out and run it up over 2000 rpm for at least a half hour.
Click to expand...

I can do this, as you and RRR suggest.

One other complicating factor that I was going to address in another thread, is I have a ticking/clicking noise to deal with and I can't find it. My hearing is poor and I can't tell where sound comes from as I only have one ear that works and that one is mediocre at best. I've had a half dozen knowledgeable car guys try to help locate it but so far no luck. I did re-lash the valves last week but I'm going to double check that. I'm hesitant to keep running the truck until I find the noise in case it's something No Good inside the engine. However, the noise has been going on for a while and it's not getting worse so I'll deal with that after I go through the suggestions above. We are in the middle of a very intense and extended rainstorm so it will likely be a few days until I can check things out.
 
halfafish said:
A little more info, to start. To break in the engine I did the initial on a run stand at a friend's house. Once it was in the truck I got it running and drove it politely for the first 100 miles or so, at varying speeds. After that I did the occasional harder acceleration as I got more miles on it. It hasn't been driven super hard but it's not been babied for the current 700 miles.

The ignition is the HEI conversion, I forgot to mention that earlier. The distributor is a Super Six with a fresh rebuild.



I'm such a newb at diagnosis, I had no procedure at all. I parked the truck from its last grocery store run and pulled the plugs a week later. I saw your process in your later post, I'll give that a try.



I have a temp gun and will give this a shot.



Yes, timing was all over the place while I fiddled with it. It doesn't help that my two best local resources, both very experienced slanters, disagree on ported or manifold vacuum. I tried them both but I don't know which was better. I currently have it on manifold vacuum and set at about 18* initial. I do not get any pinging under heavy load.



The cam isn't all that much bigger than stock, it's more of an RV cam for better low end grunt.



I can do this, as you and RRR suggest.

One other complicating factor that I was going to address in another thread, is I have a ticking/clicking noise to deal with and I can't find it. My hearing is poor and I can't tell where sound comes from as I only have one ear that works and that one is mediocre at best. I've had a half dozen knowledgeable car guys try to help locate it but so far no luck. I did re-lash the valves last week but I'm going to double check that. I'm hesitant to keep running the truck until I find the noise in case it's something No Good inside the engine. However, the noise has been going on for a while and it's not getting worse so I'll deal with that after I go through the suggestions above. We are in the middle of a very intense and extended rainstorm so it will likely be a few days until I can check things out.
Click to expand...

If you only "get it above 2K" that's fine and will work, but do know, you'll not be tuning "for the rest" of the RPM band. And that's ok, if that's how you want to do it, you can. There'll be a big part of the power circuit left out of the equation though, as at 2K, you're barely into the power circuit. That's why I've always embraced the "blast" method. You don't have to go to 5K of course, although some do......and I did with mine, but mine is more of a performance oriented build, while yours is a truck engine. Big difference. I would go to 4K pulling hard in high gear though. That's not hard on it and will likely be at the very top of the RPM band you'll take that truck engine, unless you get frisky. lol

Lastly, I think you said something about a tick? Are you going to start a thread on that so we can all argue about that too? I'll be lookin for it. lol
 
OK you just said you have the HEI conversion.

Now you need a straight wired e-coil to go with that to give you the hot spark. HEI needs the e-coil, not the old style tower coil like comes stock.

Wired with straight 12 volt, no ballast resistor. Full 12 volts.

Just like these '95 Ford F150 e-coils, they have nice flat spades and clearly marked + and - for easy wiring. They work well with HEI conversions, hot spark.
Local pick and pull for cheep too.
Screenshot_20210709-203610_Gallery.jpg


Screenshot_20210725-074319_Gallery.jpg

Screenshot_20210816-205931_Gallery.jpg
 
RustyRatRod said:
Lastly, I think you said something about a tick? Are you going to start a thread on that so we can all argue about that too? I'll be lookin for it. lol
Click to expand...

Yup. TIck/Click thread will get going when I get done working today.

George Jets said:
OK you just said you have the HEI conversion.

Now you need a straight wired e-coil to go with that to give you the hot spark. HEI needs the e-coil, not the old style tower coil like comes stock.

Wired with straight 12 volt, no ballast resistor. Full 12 volts.
Click to expand...

I did direct wire the coil, bypassing the ballast resistor. The coil is a MSD Blaster 2.


I picked up some fresh AC Delco plugs last night, I'll be installing them and report back on my findings.
 
Listening to all this internet overthinking guru crap is what got this problem started... Almost zero k.i.s.s..... this is supposed to be a grocery getter go to the dump get a load of wood simple truck and now we've went DEFCON 5.. rebuilt motor pocket ported heads custom cam four barrel intake headers fancy ignition this is nowhere in the k.i.s.s. range anymore...
Personally I'm more interested in the rod knock and waiting for that thread to start and see where that goes...
 
Good info one thing I see are four plugs that are a little rich but two that are very rich. You may consider that the carburetor is continuing to drip into the manifold after shutdown and causing the heavy carbon deposits on those two plugs. Depending on the manifold layout if that even makes sense, I have experienced a similar situation with my six pack.
 
halfafish said:
I picked up some fresh AC Delco plugs last night, I'll be installing them and report back on my findings.
Click to expand...
You'll be sorry. Every time I have ever attempted to run AC plugs in a Mopar engine whether resistor or non resistor, I have been greeted with an unbearable high pitched whine in my speakers whenever I had the radio on. Champion or autolite and stay with the basic cheap copper plugs, these engines don't really like the expensive iridium, double platinum, etc waste of money there.
 
K.O. SWINGER said:
Good info one thing I see are four plugs that are a little rich but two that are very rich. You may consider that the carburetor is continuing to drip into the manifold after shutdown and causing the heavy carbon deposits on those two plugs. Depending on the manifold layout if that even makes sense, I have experienced a similar situation with my six pack.
Click to expand...

On the right track here ^^^^^.
Now let's take a look at the orientation of the 4 bbl on the 6 cyl intake manifold. the 2 main Run Barrels are on the front half and the secondaries are on the back half.

In a perfect world if rotated 90 degrees to the right then the 2 main Run Barrels are lined up even to flow to all 6 cylinders, same with the secondaries. Check your float levels so it is not dripping in fuel after you shut it down.

Get us a picture of how your carb is sitting there on your engine, maybe we can spot something.
 
volaredon said:
Every time I have ever attempted to run AC plugs in a Mopar engine whether resistor or non resistor, I have been greeted with an unbearable high pitched whine in my speakers/QUOTE]

Good to know. In this case I'm going to run them, as the truck is super loud (no floor or other sound absorbing stuff). I can't hear the radio at all :eek:.

George Jets said:
In a perfect world if rotated 90 degrees to the right then the 2 main Run Barrels are lined up even to flow to all 6 cylinders, same with the secondaries.
Click to expand...

Here's a photo. The carb was installed with the primaries facing away from the head from the start.

DSCN1254.JPG


I broke one of the plugs doing the swap so had to get another, it's in place. I'm going to double check the valve lash in the morning, then give this the RRR plug test.
Click to expand...
 
#4 and #6 are being fouled by oil intrusion in the cylinder. Likely due to valve guide seals. Pull your cover and inspect the seals.

RGAZ
 
Shouldn't be, it's a very freshly rebuilt engine, right?
 
RGAZ said:
#4 and #6 are being fouled by oil intrusion in the cylinder. Likely due to valve guide seals. Pull your cover and inspect the seals.
Click to expand...

RGAZ said:
He stated: "Sadly, I am the goon that assembled this engine and it was my first motor rebuild."

So I am taking a shot that it was not done correctly.
Click to expand...

Good idea, I'll check that out. The head was done by the machine shop and it's a good one so (hopefully) that's not an issue.
 
The base ring reflects what the chamber looks like.
As mentioned oil is being sucked in, whether it seal or bad guide or cracked ring...maybe that's your tick/chick chick sound probably heard at deceleration?
Dont use iridium plugs, just use the v power NGK.
Tune primary for crisp off line and snap, without going wot. 'Stay under half throttle 'Then tune for wot by getting up to a 25 mph cruise and stomping on it. That's the easy way.. 2nd to just reading the tune instructions from edelbrock. The plugs in the end should be grey/tan, ceramic color tan brown ring at bottom and clean up to the top..tang should show 2 marks, 1 right at the bend near the end for initial and the 2nd the total just at or below the bend in the tang near the base ring.

The pocket porting part with big valves scares me. I've seen reversion so bad fuel was spit back out. Mostly bowl blending does little for a slant. The airflow is found in the floor and the bowl isn't capable of being enlarged much at all..as is the roof.
Oil, yes...5 and 6.
The all over the place fuel distribution?
The port work or the intake manifold...
Remove one from the equation and you'll have your answer.
 
You must log in or register to reply here.
-

Back
Top