1971 318 wonbt idle Dual points

"My '71 Chrysler 318 with

"My '71 Chrysler 318 with a Carter 4 bbl and Accel dual point distributer has suddenly developed a new problem. The engine will not idle. The rpms must be kept at 1200 or higher or it will die. This is a new and sudden development.

The boat has a new fuel tank, new fuel, new fuel filter. It has a 70's vintage Accel distributer. I found that it is not firing on all 8 by pulling out the spark plug wires one at a time and replacing. Sometimes a difference in engine sound was noticeable, sometimes not. I am suspect of of the dual points as pair appear like new and the other appears tired. The cap looks like it could use a replacement too.

Its sudden onset of symptoms has me perplexed.
Any other ideas?"

"Have you checked the timing?

"Have you checked the timing? At higher RPM the effect of the loss of one plug is less noticable. Even so, like you I suspect it's a carb problem. Possibly your idle port is plugged? Assuming you have good pressure from the fuel pump it may be a stuck float or needle? All new fuel parts may have kicked loose some debris into the carb?"

It is possible. There is a 10

It is possible. There is a 10 micron inline filter between the tank and the fuel pump. The old tank had a ton of rust in floating in the fuel. It ran better with the old tank and dirty fuel!

How do you clean an idle port?

"Turn the idle mixture screws

"Turn the idle mixture screws al the way in and see if themotor dies or runs differently.

..."There is a 10 micron inline filter between the tank and the fuel pump"

Not good! Use 30 or coarser before, and 10 micron after.

Jeff"

"Yes, the idle does improve or

"Yes, the idle does improve or degrade depenging on the mixture setting.

I didn't know a 30 micron filter was available... I thought they were all 10.

I just took the boat out for a spin, it started, it idled, after a 1/2 drive I came home and she stalled while trying to dock. It was apparent as I accelerated slowly, she's not hitting on all 8."

"I have continualy found that

"I have continualy found that the most difficult troubleshooting is when multiple problems are the root cause. Sometimes you do something and it helps but it's not the primary cause. Keep an open mind when diagnosing as there often exist multiple symptoms that are each minor but as an effect upon the whole engine manifest confusing behavior. At that point, go simple, it's got to be fuel or spark, very rarely mechanical.

Pull the coil to distributor wire, then loosen the fuel pump line to the carb and put it in a can. Turn the engine over and you should get hugh squirts of fuel.

At your reliable higher RPM try pulling each spark plug lead, slip the boot back or insert an insulated screwdriver and see if you get a healthy spark to the manifold, (safety: wear insulated gloves or use insulated channel pliers and make sure there are no fuel vapors about). Did you check the timing mark with a strobe? Does it advance when the throttle increases? Is the distributor base clamp loose?

If either of these detect no problem then I'd say it's the carb. If you are not sure of the carb and how to tune it, get a manual or get a mechanic to help!

Note; the 30 micron filter filters out larger particles than the 10m and should be between the 10 micron and the fuel pump. My Sabre 26' has a large cannister water separator/filter mounted above the pump and then a small inline filter right next to the carb, also a sponge metal filter in a carb cavity at the fuel inlet."

"Ok, can do.

How do you k

"Ok, can do.

How do you know what your points are shot? What are the symptoms? I understand a distributer with a single set of points, and even how to replace them. However, dual points, are a mystery. How do I figure out the gap? Is it the same as if it were a single point distributers just times two?

I did pull my spark plugs and they actually look great;not wet, not foul, not oily, just like all the picture on the net show how healthy plugs should look."

"I still think the carb is sic

"I still think the carb is sick. I got some gunk in the fine passages of mine that required drilling them out to get rid of. Ran great above idle, but awful below that.

Jeff"

"DUAL POINTS ARE EASY,
Lets a

"DUAL POINTS ARE EASY,
Lets assume that the the distributor has 8 lobes.

The points are mounted on the plate, 10 degrees offset from each other.

Dwell is the same (28 - 32) for each set of points.

.. stick a piece of cardboard from an ing. component between the contacts of a set of points, while you check the other set.

Combined d=well should be about (38 - 42) I forget the exact spec, but that is in the ballpark.

THE LAST SET of points to open will determine your ing. timing. IF that is your failing set, your timing will be off, or jumping back & forth, erratically.

Make sure that you have done FastJeff's "play with your Rotor a million times, while listing to your favorite tune " trick.

Fred 156-M"

"Tomorrow my mechanic will ins

"Tomorrow my mechanic will install a "new used" Chrysler distributer and the ACCEL distributer will be trashed. He will also install a Prestolite Electronic Ignition system, new cap,rotor, plugs, wires, and a new ignition/key switch. The latter because if you wiggle the key while she's runnning the engine will shut down! Anyone want to guess at the cost of this changeover and ignition update? Hmmmm at 90.00 an hour plus parts......."