reading the slant six plugs color

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64longroof

64longroof

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This picture is of the plugs of my slant, freshly rebuilt, 1800 miles of break in.
It has a calculated 9:1 compression, split exhaust, Carter 1 bbl, running 10 deg advanced.
I noticed it sometimes runs on 2-4 chugs after turning off. Maybe once every ten turn offs.
I use 89 octane.
Anyone have an idea if this is within a normal range for recent rebuild? I just think there is
an awful lot of variance in the plugs color, oil dampening in middle.
All are 12 Y. THanks.

IMG_20190704_175851346_HDR.jpg
 
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Gas fouled plugs, timing not correct. What year model /6 are you working on? Timing varies depending on early model non smogger, or late smogger motor.
 
That's quite a variance. I'm no expert but looks gas fouled.

Is your ignition in good shape? I used ignition parts recommended by SSD including NGK extended plugs. You might try those or go to a hotter plug.

I should really check my plugs, about 8000 miles on 100% rebuild. Maybe I'm whistling past the graveyard but it runs so good I just drive it.
 
If you have the early slant head with that removable cup that the spark plug goes in, make sure to torque it to spec. Also what kind of camshaft do you have? And have you recurved the distributor, I believe your running on (dieseling) is due to too much curb idle and not enough initial timing. Being able to give it More initial timing will allow you to lower your curb idle. This is an issue that happened when you up the compression and don’t recurve your distributor. I would order the fbo limiter plate and set it at 18 degrees and take out the have spring and replace it with a mr. Gasket light spring, that should put you in the ball park.
 
What are we lookin at? 15 minutes at idle? You cannot just "take plugs out" and read them. There is a procedure.
 
Thanks all for looking, even heat miser!
Itis the old slant with the plug tubes.
Cam is the late slant six cam for Volare. Pretty mild.
Dist. is a rebuilt, with one of those dark blue springs. Can't recall the other spring. I tried to get as loose a one as could find among a few dists.

"This is an issue that happened when you up the compression and don’t recurve your distributor. I would order the fbo limiter plate and set it at 18 degrees"

this works with points type dist?

" and take out the have spring"

Half spring?

Are you saying, I can't advance timing with a light, becasue I will just get more dieseling, that
I need to get the advance via the weaker springs?
 
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Heat miser is correct. I only said the engine had 1800 miles break in. Easy to assume that means 1800 on plugs.
I did write on the cardboard in the picture, 1800 miles. That IS how many miles are on
those formerly brand new plugs. "He's too much!"
 
64longroof said:
"This is an issue that happened when you up the compression and don’t recurve your distributor. I would order the fbo limiter plate and set it at 18 degrees"

" and take out the have spring"

Half spring?
Click to expand...

He meant to say there are 2 springs in the distributor, remove the HEAVY spring and replace it with a lighter Mr. Gasket spring. Keep the original lighter spring that is there.
 
Thank you Kosmic..............is it visually obvious which is lighter or do you have to tug on them
to tell? more or less loops in one vs other?
And if I look in there and see two identical looking springs because I made the error of putting in identical springs , can you tell me the location of the heavier one ? Like is it closer to the points? Dfferent mounting tag?
 
I just thought of something that may or may not have anything to do with this.
I'm putting a G3 Hemi in my 68 and last fall I sold my 318 and 904 kind of suddenly. That left me with a gas tank 3/4 full of 93 octane. I siphoned it out and quickly filled a 5 gallon gas can. I put some in the Jeep Comanche, some in the Subaru and some in my John Deere lawnmower.

I started cutting the grass and within a few passes the OHV Kawasaki engine in the mower started sputtering, smoking and lost fire. I drained the gas, cleaned the plug and filled the tank with my usual alcohol-free gas. Fixed! It was the damnedest thing. That low compression banger just did not like high octane. Maybe a low compression slanty is similar. I run 87 octane in my rebuilt 225 and never have a problem.
 
64longroof said:
Thank you Kosmic..............is it visually obvious which is lighter or do you have to tug on them
to tell? more or less loops in one vs other?
And if I look in there and see two identical looking springs because I made the error of putting in identical springs , can you tell me the location of the heavier one ? Like is it closer to the points? Dfferent mounting tag?
Click to expand...
I don't think it matters which spring goes where. They control the rpm where the advance weights move away from the center due to centrifugal force thereby advancing the breaker plate. It is visually obvious which spring is heavier as the wire diameter is larger with fewer coils.
Pictures from 1964 Valiant factory service manual.
I really don't think you have to get into this yet. Verify the basic tuneup first and make sure you have good quality ignition parts. Maybe recheck things and try it again. A good rebuild on a slant should run good right out of the box without much variation from stock specs.

20210312_143807.jpg


20210312_143840.jpg
 
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64longroof said:
Thank you Kosmic..............is it visually obvious which is lighter or do you have to tug on them
to tell? more or less loops in one vs other?
And if I look in there and see two identical looking springs because I made the error of putting in identical springs , can you tell me the location of the heavier one ? Like is it closer to the points? Dfferent mounting tag?
Click to expand...

Yes get the fbo plate and take timing out of your distributor set it at 18 limit slot put in the mr gasket light spring leave in the original lighter spring that came with the dizzy. Add more initial timing and lower your curb idle adjust mixture and go. Your problem is higher compression with late timing equals a lot of curb idle which equals to run on aka dieseling. You will feel a hell of a difference.
 
Mine looked similar when I got it. One of the many problems I found was the float on the "rebuilt" carb set incorrectly (Holley 1920).
 
Kosmic, if I have another spring thats the same gauge as the lighter one in the Figure,
could I just try that one in replacement of the heavy one, or is the Mr. Gasket preferred for some reason?
Yeah, a tank of regular gas would probably be an interesting test before digging into the distributor. I think one of the point contacts has some pitting. But I kept the set, as it is
from Standard. I sanded them best I could. The dwell is 46, which if I recall , is in spec.
But that may be irrelevant with the higher compression.

Thank you all for taking the time to read and think. This was the car when I got it from Kenny and Brian. I drove this from Atlanta area to Lex Ky. Ignition relay stopped me at a gas station, but I jiggled it and made it home. There ARE guardian angels.

2 wagons99.jpg
 
64longroof said:
Kosmic, if I have another spring thats the same gauge as the lighter one in the Figure,
could I just try that one in replacement of the heavy one, or is the Mr. Gasket preferred for some reason?
View attachment 1715706485
Click to expand...

I think that's what I did with mine, used 2 of the factory lighter springs. That will increase the advance rate a little, just not as much as the super light spring. I'll defer to @Slantsix64 as I just don't have his experience.
Regardless, you should probably put new plugs in, I used the extended tip NGKs that Slant Six Dan recommended. They are the smaller plugs with 5/8" hex but you still remove the washers. He says they are the best for a slanty. www.forabodiesonly.com/mopar/threads/spark-plugs-for-slant-six.130467/#post-1972971916

P.S. a GOOD condenser reduces point pitting. I still have points in mine too and checked the dwell before driving to Carlisle last July (320 miles each way on one tank) and it was in spec.
********
I actually have the FBO limiter plate and lighter springs in my stash but I wanted to experience the "pure" slant six excitement before I started changing things. My parents had 61, 63, 67 and 73 slants but this is my first. I've been collecting parts and have split exhaust manifolds and a 2 barrel intake with carb to go on but first....swapping in a 4 speed that I'm in the middle of rebuilding. I tried "racing" my 64 Val with the 3 on the tree and it was not too good. Managed a best of 18.51 but I'm curious what it'll do with a trans I can actually shift quicker.
 
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KosmicKuda said:
I think that's what I did with mine, used 2 of the factory lighter springs. That will increase the advance rate a little, just not as much as the super light spring. I'll defer to @Slantsix64 as I just don't have his experience.
Regardless, you should probably put new plugs in, I used the extended tip NGKs that Slant Six Dan recommended. They are the smaller plugs with 5/8" hex but you still remove the washers. He says they are the best for a slanty. www.forabodiesonly.com/mopar/threads/spark-plugs-for-slant-six.130467/#post-1972971916

P.S. a GOOD condenser reduces point pitting. I still have points in mine too and checked the dwell before driving to Carlisle last July (320 miles each way on one tank) and it was in spec.
********
I actually have the FBO limiter plate and lighter springs in my stash but I wanted to experience the "pure" slant six excitement before I started changing things. My parents had 61, 63, 67 and 73 slants but this is my first. I've been collecting parts and have split exhaust manifolds and a 2 barrel intake with carb to go on but first....swapping in a 4 speed that I'm in the middle of rebuilding. I tried "racing" my 64 Val with the 3 on the tree and it was not too good. Managed a best of 18.51 but I'm curious what it'll do with a trans I can actually shift quicker.
Click to expand...

Komickuda, you are correct using the two lighter springs from the factory will make a decent curve. Using the Mr.Gasket spring with the factory spring will bring it all in by 2400 heres a good article on all this
More Power For Your Leaning Tower: Add 14-Horsepower To Your Slant 6 - Mopar Connection Magazine | A comprehensive daily resource for Mopar enthusiast news, features and the latest Mopar tech
 
Slantsix64 said:
If you have the early slant head with that removable cup that the spark plug goes in, make sure to torque it to spec. Also what kind of camshaft do you have? And have you recurved the distributor, I believe your running on (dieseling) is due to too much curb idle and not enough initial timing. Being able to give it More initial timing will allow you to lower your curb idle. This is an issue that happened when you up the compression and don’t recurve your distributor. I would order the fbo limiter plate and set it at 18 degrees and take out the have spring and replace it with a mr. Gasket light spring, that should put you in the ball park.
Click to expand...
What is a fbo limiter plate ? Thanks
 
KosmicKuda said:
I just thought of something that may or may not have anything to do with this.
I'm putting a G3 Hemi in my 68 and last fall I sold my 318 and 904 kind of suddenly. That left me with a gas tank 3/4 full of 93 octane. I siphoned it out and quickly filled a 5 gallon gas can. I put some in the Jeep Comanche, some in the Subaru and some in my John Deere lawnmower.

I started cutting the grass and within a few passes the OHV Kawasaki engine in the mower started sputtering, smoking and lost fire. I drained the gas, cleaned the plug and filled the tank with my usual alcohol-free gas. Fixed! It was the damnedest thing. That low compression banger just did not like high octane. Maybe a low compression slanty is similar. I run 87 octane in my rebuilt 225 and never have a problem.
Click to expand...

Interesting , I run 93 non ethanol in 2 john deere lawn tractors, chainsaw, leaf blower , and my 505'' barracuda , no problems w/ any of them .
 
famous bob said:
Interesting , I run 93 non ethanol in 2 john deere lawn tractors, chainsaw, leaf blower , and my 505'' barracuda , no problems w/ any of them .
Click to expand...

I should mention that the 93 octane I drained from the 68 was fresh but had ethanol in it.
I remember talking to the guy in a lawn mower repair shop about 20 years ago when I was buying a carb rebuild kit. He said to use non-ethanol and fuel stabilizer in my yard equipment so that's what I've been doing. It took me a while to find non-ethanol and the octane is not marked on the pump but I'll have to ask this week when I get some more. It's a couple bucks more than regular so part of that may be due to the higher octane.
 
KosmicKuda said:
I should mention that the 93 octane I drained from the 68 was fresh but had ethanol in it.
I remember talking to the guy in a lawn mower repair shop about 20 years ago when I was buying a carb rebuild kit. He said to use non-ethanol and fuel stabilizer in my yard equipment so that's what I've been doing. It took me a while to find non-ethanol and the octane is not marked on the pump but I'll have to ask this week when I get some more. It's a couple bucks more than regular so part of that may be due to the higher octane.
Click to expand...

Usually about 80 cents a gallon higher here .
 
Has someone in the past run the wrong plugs or plugs with washers and carbon fouled up the threads? preventing those plugs from sitting at the correct depth? Thats a wild difference from plug to plug?
 
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