Cylinder has spark but not firing..

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That's a start. I don't want to pull the cam out and find out it was something else. Ill check when i get off work and make sure that all the valves are moving up and down. Then I'll make sure that were pointing to #1 cylinder. It sounds like everyone thinks that the cam has a bad lobe or 2 on it.
 
"Pointing to #1 cylinder."

I keep trying to tell you this is NOT repeat NOT a timing issue. Cam or ignition timing WILL NOT affect only one or two cylinders
 
67Dart273 said:
"Pointing to #1 cylinder."

I keep trying to tell you this is NOT repeat NOT a timing issue. Cam or ignition timing WILL NOT affect only one or two cylinders
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Ok so then lets take this out of the equation. I somewhat agree because if it were a timing/ cam issue, i don't think the car would even start. Ill check the valves after work and make sure they're all opening and closing.
 
Well that's not quite right, either. Any mechanic has seen numerous 60s/ 70's cars which had worn out "slipped" nylon timing sprockets drive (poorly) into the shop, coughing and gagging.

An engine WILL run under certain conditions with the cam or ignition out of time, and while running poorly, you won't be able to pin it down to "just one" or two cylinders

If this were me, I'd do this............

Carefully rotate the engine, watching for proper valve opening / closing on each cylinder

MAKE CERTAIN ignition is OK. You can swap plugs and wires from one cylinder to another and see if the problem moves.

Do NOT "pull" plug wires. Instead, SHORT them to ground with a clip lead and screwdriver, or other grounded probe. On older cars with conventional distributors, I usually do one of two things..........

Either pull up the dist. boots and insert small brads / nails down beside each wire, so you can go 'round and ground one at a time.

or........

Pull one wire out one at a time and at the same time, slide your ground probe into the dist. cap

Listen as each cylinder is dropped, use a tach or vacuum gauge. Each cylinder should drop the same

Once you ID the one, the two, or whatever "bad" ones, MOVE those plugs, or replace them and retest.

Then move the plug wires to other cylinders and retest.

If the two cylinders are adjacent, suspect a leak between cylinders. This should show up with a pressure test, but may not

Buy or make yourself a leakdown tester. Google it.....they are easy to make.

Inject air into each cylinder at TDC and listen for leaks........at the carb, at the tail pipes, and in the radiator cap, and look for bubbles in the coolant.
 
The first thing I would do is a cylinder leakage test on a cold motor. anything over 10% is a fail.start there. And as any tech can tell you just because the parts are new or rebuilt doesn't mean there right.:happy1:
 
Good GAWD. One step at a time. Compression seems fine. Do you have a volt ohm meter? Measure the resistance of the two wires on the skipping cylinders and see how they compare to the rest. They will be different because of the difference in length, but if they are stupid different then you have plug wire issues. Lets rule the simple stuff out first.
 
Not as long as they are in good shape and adjusted correctly.
 
How much more info do you plan on leaving out?
 
As Rob said........if you have points ignition...........!!!?!?!??!??!?!??!?!?!???????????

It IS possible that if the points are worn to the point of bbbbbaaaaarrrreeeelllleeeeeeeeeeeeee

opening, or if the dist. shaft has a little "wobble" that two adjacent cylinders might not open the points.

Didn't you say you have spark?

But this is why you short plugs one at a time, and actually check stuff. I guess I've done this so many times it's all inbred. "While" you are shorting out individual cylinders, this gives you a chance .......with your shorting probe...... to see how good or bad the spark IS
 
RustyRatRod said:
How much more info do you plan on leaving out?
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Nope that's pretty much it man lol. I got the motor from a 78 Cordoba. The previous owner of the barracuda put a new points style distributor in it with new points cap and rotor. I'm converting to electronic tomorrow to see what happens. I planned on doing it anyways I guess now would be a good time
 
duey_roc said:
So ive had this 360 torn apart 3 times now and im going to scream since ill most likely be doing it again. Heres whats going on...
What does everyone think? angry9:
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1. Make sure you're getting fuel into the carb. If you move the throttle back, does the accelrator pump shoot gas into the venturis?
2. Get a cheap spark tester - plugs into between the plug wire and the spark plug. Test at least #1 plug. It should light readily every 2 crank cycles.

If the above 2 are good, it should at least be spitting or backfiring. If your getting "no action", in my experience it will be one of those 2. Occam's razor.
 
And yes I've had this motor apart in 3 different situations. It's been kind of an experiment just to see out of curiosity. For example I wanted to know what would happen if you ran a solid cam on a hydraulic lifter. It actually worked but decided to switch to a stock cam. I've had the heads redone so I pulled the old heads and put the j heads on. I've had to take the intake off twice alone because of vacuum leaks. Then i tried running the motor with the stock 318 torque converter. That doesn't work because the 360 is externally balanced and I didn't have weights on the converter. So now I'm at this and I'm still learning. I've just never had this problem before. Gonna try converting to electronic ignition tomorrow and see what happens
 
You did not happen to leave rags or paper towels in the ports when putting it back together?
 
Had this same kinda thing happen before but on 2, 4 cylinders. It had a miss in those two, sold the truck and the guy brought it back to show me the problem. It was a crack on the bottom side of the intake.
 
68'barracuda said:
Had this same kinda thing happen before but on 2, 4 cylinders. It had a miss in those two, sold the truck and the guy brought it back to show me the problem. It was a crack on the bottom side of the intake.
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Interesting. I can see how that's a possibility. The intake is an old edelbrock ld4b intake
 
68'barracuda said:
Had this same kinda thing happen before but on 2, 4 cylinders. It had a miss in those two, sold the truck and the guy brought it back to show me the problem. It was a crack on the bottom side of the intake.
Click to expand...

So I did a huge amount of tests on the motor today. The only thing I can think of is that it has a crack on the bottom side of the intake. This would explain why I can't adjust the air mixture screw on my carburetor and why the exhaust smells and looks bad. I'm gonna try a new intake manifold and see what happens
 
duey_roc said:
So I did a huge amount of tests ................. I'm gonna try a new intake manifold and see what happens
Click to expand...

You are shootin' in the dark with no moon and using outdated ammo. You are using an unsafe firearm, and you are liable to hit or miss just about anything. You are just about out of ammo and don't have a ride home. There are no gas stations for a hundred miles.

What I mean by this, is that there is very very little chance that you have a cracked intake. I'm sure it can and does happen.

I would bet you need to sit down (not drink beer) and think carefully about what you have done, what you have tried, and what the results are.

You say you did a bunch of tests.

What EXACTLY did you do and what are the results.

EXACTLY which cylinder(s) don't fire?

How did you determine this?
 
just to be sure, is your spark orange or blue? and im gonna agree with 67 dart. this is not a timing issue. its a fuel/air issue, and ive had 318s that will run 180 out but they dont run well
 
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