Cylinder has spark but not firing..

[duey_roc]

so you ordered another Intake manfold before taking the old one off to confirm it has a crack....

I think the head is cracked...and it is not the one on the engine....lol

We already know this lol. Ya i bought it used from someone on this site a while ago. Still waiting for it to be shipped :wack: I kind of wanted a new intake anyways because this one has some stripped threads and looks pretty tired. Plus, the intake runners and ports on the performer match up a little better than an LD4B on a 360.

 

[Cudafever]

ok duey Vary nice on the volt ohm pic!!!

So did you do it again on 20m? you don't need to post up pic just jot down the numbers.

 

[teringer]

the ld4b manifold is square base/ for holly/afb design. the performer that I have use TQ or QJ do you have a different carb or adapter to use?

 

[duey_roc]

ok duey Vary nice on the volt ohm pic!!!

So did you do it again on 20m? you don't need to post up pic just jot down the numbers.

No i havent gotten to do it yet.I will definitely do it when i get off of work tonight.

the ld4b manifold is square base/ for holly/afb design. the performer that I have use TQ or QJ do you have a different carb or adapter to use?

The one i bought is an Edelbrock Performer 318/360. I had one a while back and it fit my holley square bore. This one looks like the same style.

 

[duey_roc]

the ld4b manifold is square base/ for holly/afb design. the performer that I have use TQ or QJ do you have a different carb or adapter to use?

This is the one i bought.

 

[RustyRatRod]

What carburetor do you have on it? If it is not a spread bore, it requires a thin metal plate to seal off the wider secondary side. If you do not have that, you have a vacuum leak.

 

[duey_roc]

What carburetor do you have on it? If it is not a spread bore, it requires a thin metal plate to seal off the wider secondary side. If you do not have that, you have a vacuum leak.

I have a Holley 790 on it. It's a dual feed. Non double pumper. Wouldn't the rpm rise when I sprayed carb cleaner around the carburetor base if I had a vacuum leak? I tried that around the base and the entire intake and nothing happened

 

[RustyRatRod]

A 790? Never heard of that one. I don't know. I don't use carburetor cleaner. I use water. I'm smart enough not to literally pour gas on the fire.

All I know is, if you have a square bore carburetor, you need the metal plate I described.

This:

http://www.summitracing.com/parts/sum-g1420/overview/

 

[duey_roc]

Interesting. I'll have to invest in one of those. What will happen if you use water? Same rise in rpm?

 

[gliderider06]

Since you are dead set on changing the intake because it is your problem, I will be interested in buying it from you, for the right price. post a picture of it and I just may purchase it from you.
I think you are just opening up another can of worms by swapping manifolds before verifying that is/was your issue. Let me know when you sell that intake.

 

[duey_roc]

Since you are dead set on changing the intake because it is your problem, I will be interested in buying it from you, for the right price. post a picture of it and I just may purchase it from you.
I think you are just opening up another can of worms by swapping manifolds before verifying that is/was your issue. Let me know when you sell that intake.

Well I had already made it set in my mind I wanted a new intake anyways. And I'm hoping this is the issue but we will see. You never know until you try

 

[duey_roc]

Sounds pretty simple.
1. Spark but not running on those cyl
2. Oil fouled plugs

Intake leak, or multiple wild shots from a tennis player resulting in the ball getting stuck in your intake runners while you had it apart last time.

Pick one that seems most reasonable.

Haha! Dude that's it! I remember this guy walked past my car when I came back from inside the house. He was holding a tennis racket :happy6:

 

[duey_roc]

Alright so i completely went through this entire thread one more time and wrote down all the recommendations and tests that people want me to do. Here they are...

#1 Compression check, DONE
#2 Leak down test, NOT done
#3 Check for valves opening and closing, DONE
#4 Check for cracks or carbon buildup under distributor cap, DONE
#5 New plugs or rotate them around, DONE
#6 Squirt water around intake and carb base, DONE
#7 Check for straight pushrods, DONE
#8 Check for wiped camshaft, DONE
#9 Check ohms between wires, DONE but retrying
#10 Check for intake alignment pins left in, DONE (i remember theyre not in)
#11 Lay straight edge across valves, NOT done
#12 Vacuum check, NOT done
#13 Loosen rockers back 1/2 turn, DONE but retrying.
#14 Left rags, towels etc inside motor? DONE and no i didnt lol.
#15 Cover crankcase breathers and vacuum test oil level tube, NOT done

Everything that i have not tried im trying on saturday and sunday. Sorry if im on edge guys. Ive had this car for 6 months and im stressed cuz i want it running already. Ive NEVER had this much issue with an engine. So bear with me! Thank you very much for the ideas and things to try.

 

[duey_roc]

I decided i would go out and retry the resistance reading right now on the 20k setting. Heres what i got.

#2 is 9.35
#4 is 8.88
#6 is 7.76
#8 is 8.05
Coil is .01
#1 is 8.15
#3 is 8.07
#5 is 7.20
#7 is 8.38

Does this look right? If it's ok, what would an example of bad resistance be?

Also, here is my #2 and #8 cylinder plugs. Now that i look at them, they dont look oily, but you guys give me your input. Much appreciated! :happy1:

 

[RustyRatRod]

BWAHAHAH! Really dude? If this thread, is "pissing" you or anyone else off, you need to find a different thread to post in. Dude is asking for help, if you don't want to offer help, then move along. Stop treating this guy like hes a child, with your own childish behavior. And to "67Dart273" it was cute you said bye!

Well you told him to go buy a new car, hippiecrit. lol

 

[peedee]

#8 Check for wiped camshaft, DONE

How can this be with the intake still in place or has a dial indicator been used to measure valve lift.
I think it would need to be down to near base circle diameter to really evaluate by eye for this poster,
I use a 2inch accessory style vacuum gauge the type that summit sell for $15.72 http://www.summitracing.com/int/parts/sww-122261/overview/ then iam sure someone has a chart that will let you use the gauge readings for a diagnosis, i was going to link you to a site but when i went to it the data was gone (the site was hacked a couple of months ago and i do not think anyone has missed the data yet)
I have just got back and re-read all of the posts,not meaning to be mean but you seem to be a fiddler with minimal knowledge of what you are doing

 

[RustyRatRod]

My money says he's shootin in the dark and hasn't done half what he says on the list. I smell a troll. Jes sayin. This is quite entertaining.

 

[duey_roc]

not meaning to be mean but you seem to be a fiddler with minimal knowledge of what you are doing

Yes we ALL know that I should hang up my wrenches and never touch a car again. Stated multiple times by numerous ppl. Thanks for adding to the number.

I checked the cam before installing it. I didn't put a gauge or dial on it but none of the lobes looked rounded off. To have a misfire in a cylinder, I would think the cam would have to be pretty rounded off, not just slightly wore. My dart sport had a rounded out camshaft completely. It sounded like a rod knock. I assumed that's what it was so I pulled the motor to find out it was the rear camshaft lobe. It was rounded off completely.

What I'm saying is there's no knocking or banging or clanking. Plus, like I said, I wouldn't have put a camshaft in that looked bad or even lightly wore down. They're cheap enough that I would replace it at that point

 

[duey_roc]

My money says he's shootin in the dark and hasn't done half what he says on the list. I smell a troll. Jes sayin. This is quite entertaining.

I'm done. I'll figure it out on my own. I've never seen so much negativity come from ONE person before. Instead of trying to be helpful you're "money" is that I'm shooting in the dark and not doing what I said I've done. Go get a life dude instead of posting on this website and pissing off people that want to learn more. That's the WHOLE reason I started this thread.

 

[moparlover]

it's probably a plug wire with a worn spot grounding out.

when he removes the plug from the cylinder and checks for spark (cranking with plug wire on the plug) the wire is moved and not grounding on a header or whatever...

 

[gliderider06]

Just because a cam WAS good when you put it in does not mean that it will not wipe out after it is installed. A flat tappet cam will wipe out MUCH faster with today's low zinc oils especially if you do not use an additive, break in oil, proper break in procedure, used/mismatched lifters.
Are you sure your carb is good? Jetted properly? Power valvegood? tuned right? A 750/790 as you say you have, is way too large for a stock 360. The pictures of your plugs, to me, show a rich condition. A points dist will not give a good strong spark like an electronic/HEI/MSD type ign.
You should take all your plugs out in the order that they are in the engine and take a picture of them, so we can read them. the reason I say this, I just had an engine with plugs that looked like yours on 4 cyls. #1,7,4,6. I pulled the carb apart and found the jet was larger on one side of the carb, which was giving the 4 cyls an overly rich cond.
You never mentioned anything about your carb tune. Fuel, air, spark

 

[75dartsport]

The picture of the plugs above are two different heat range plugs? Why are all the plugs not the same?

 

[teringer]

that's the first thing I noticed also ? n14y/n9y?

 

[gliderider06]

Hey, He said they were new not that they were the correct plugs. Goes to show a picture is worth a thousand words. In this case, several thousand words! I wonder how many more don't match? I would suspect that is a good bit of the problem

 

[magnumdart]

Spark plugs far worse can still work. If he swapped the plugs around and the same cylinders miss-fired (or didn't fire at all) probably not a plug issue. The gap looks a little off though, but hard to see thousandths of an inch on a 'putor screen.