Would this cause a black plug? Dannymax and others

[93max]

Well my son was/is having issues with one cylinder breaking up. IE really fat/black sooty plug?
Could this be the issue?
I would think so but what do I know.
That's why I'm asking people who do!
What's different/missing from one of the carbs?

 

[Fire-medic]

Looks like the needle seat has backed-out of the hole it rides-in. Can you get any-more clear pics?

 

[93max]

Looks like the needle seat has backed-out of the hole it rides-in. Can you get any-more clear pics?

Winner! :clapping:
There's nothing there!

 

[93max]

He ordered a new needle jet.

 

[93max]

It goes up from the bottom.

 

[dannymax]

Did you pull the float chamber cover? There's no emulsion tube (needle jet) at all?

 

[93max]

Did you pull the float chamber cover? There's no emulsion tube (needle jet) at all?

Yes he did.
He didn't notice it when he cleaned them.
He said the rest of the emulsion/main jet it there.
Just the top portion (needle jet) is/was missing.

 

[dannymax]

I'm not sure if gas could be pulled up from the main with the tube and brass bolt/washer missing....seems like it would just pull air down thru the vent elbow.

Guess just see how it runs with the new tube in...do you have the brass bolt & washer that holds the tube in the jet block?

 

[93max]

Unless I'm thinking of it wrong, wouldn't the fuel always be pulled up through the main past the needle even at idle when the pc in the picture is missing?
There is nothing to stop the signal as there is clearance all around the needle subjected to vacuum.

 

[dannymax]

Are we talking about a VMax carb?

 

[93max]

Are we talking about a VMax carb?

No. I'M sorry! I pm'ed you about my sons 79 CB 750 remember! LOL! :biglaugh:
Sorry to everyone else too. I guess I figured it was a cv style carb so it would be similar.

 

[93max]

Yeah the cv part is where it stops. His is vertical and ours is horizontal.

DUH! :bang head:

 

[dannymax]

Yeah the cv part is where it stops. His is vertical and ours is horizontal.

DUH! :bang head:

Haha....no problem. Let us know how it turns out.

 

[93max]

Haha....no problem. Let us know how it turns out.

Will do!
Fingers crossed!

 

[93max]

Well that was it!
Runs like a 1979 CB 750 now!
Finally!

 

[dannymax]

Cool!! :clapping:

 

[93max]

Cool!! :clapping:

Yeah, my neighbors are heal happy too! :biglaugh:
I give my son a lot of credit.
I would have rolled it into the Hudson 2 months ago!
He must have went through the ignition 4 times and the carbs 4 times...but he finally found it!
I'm proud of him!
The weird thing is he just started in the last couple of years getting into working on stuff.
I've had my Nova for 17 of his 22 years and he never wanted to work on it with me.
That's ok too. Not everyone is like me.
His little brother tho was always curious and wanting to learn about engines and working on cars.
I guess it's ok, he graduated out of NJIT as a Civil Engineer this May and got a great job with the construction company he interned with.
So I guess it was better then him slacking on school and working on stuff.
I'll stop bragging on my son now. LOL!