Breaker Plate stuck/Vacuum advance/Quick help please

[Big_John]

Had to test this
-69 383 distributor. Can easily move advance with sucking.
Next had to find my Autometer boost/vacuum gauge, 41 cmHg. its around 16inHg

Well... OK... as I said, I really don't know how much negative pressure or vacuum you can generate. It surprises me that you can...

 

[GG-1]

Push it in manually and put your finger over the nipple. It should stay in. If it returns, the diaphragm is shot.

Yup. It is undeniably shot. It feels as if I'm pushing the metal arm against the heavy spring inside.. with no diaphragm present at all, and it just snaps right back out, no matter what I put over the nipple hole.

 

[Turboomni]

Does it hold a vacuum without bleeding down?

So what you figuring on doing?

 

[GG-1]

I'm scouring the interwebs looking for a good working canister replacement. I'm looking at NOS units mostly. I don't want a poorly made chinese built unit that's gonna fail in a month.. I'd rather buy an inexpensive, used, quality, functioning unit!

I'm a bit overwhelmed with all the technical information I'm getting regarding the order in which to do diagnostics/troubleshooting, tuning, timing, etc..

My plan is to:

-replace the vacuum advance
-check spark plugs and wires
-vacuum check entire system for leaks
-compression test
-check/set timing
-get & set new points and condenser
-check/set dwell
-replace ignition coil
-replace ballast resistor
-adjust carburetor once timing is intially and totally set
-drive car
-tune carburetor & ignition more
-drive car
-continue to tune & adjust timing with carburetor until she drives smooth as silk and with good power at any rpm.
-learn how to do all of the above.

I've still got to buy the following tools to accomplish it all:

-a dwell meter
-a timing light/gun
-a set of good feeler gauges
-a vacuum gauge(mityvac hand pump?)
-patience

-or just find a good mechanic locally and roll the car to their garage.

 

[GG-1]

Does it hold a vacuum without bleeding down?

So what you figuring on doing?

It is undeniably shot. It feels as if I'm pushing the metal arm against the heavy spring inside.. with no diaphragm present at all, and it just snaps right back out, no matter what I put over the nipple hole.

 

[Turboomni]

but does it hold a vacuum without leaking down?

 

[GG-1]

but does it hold a vacuum without leaking down?

No.. What I'm saying is there is no vacuum to hold. There is only spring tension. Imagine the canister without a diaphragm inside. Only a very strong spring.
As I apply an enormous amount of pressure, the metal arm is just hitting, clicking and pushing on the metal spring inside and snapping back when I release the pressure, whether I suck on a tube.. cover the hole, or not.

 

[Turboomni]

I am sorry but what I would like to know is if you put a rubber line on it like the vid you posted and apply vacuum with your mouth will it hold even though the arm is not moving for any length of time?.


The reason I ask is if it does hold a vacuum without bleeding down the diaphram is good and something else is holding it up. There is a hex bolt inside the vacuum nipple it self that might have been adjusted so there would be no advance. If it does bleed down the diaphram is toast and there is no hope for the unit.

 

[GG-1]

I am sorry but what I would like to know is if you put a rubber line on it like the vid you posted and apply vacuum with your mouth will it hold even though the arm is not moving for any length of time?.


The reason I ask is if it does hold a vacuum without bleeding down the diaphram is good and something else is holding it up. There is a hex bolt inside the vacuum nipple it self that might have been adjusted so there would be no advance. If it does bleed down the diaphram is toast and there is no hope for the unit.

My unit is not the adjustable type. The adjustable units have hexagonal shaped canister bodies like below:

 

[Turboomni]

Ok didn't know that.

 

[GG-1]

Ok didn't know that.

Yeah, last night I was reading a good little article about adjustable vacuum and vacuum in general.. worth checking out for anyone really:
Tuning in a Vacuum - Power & Performance News

So knowing all that, it may be beneficial to use an adjustable vacuum advance to gain stability and performance on our street cars.

 

[Turboomni]

Well good luck to you finding one and if you do have any info to share of other ones lurking about for sale any where let us know.

 

[70bigblockdodge]

Car will run fine without the vacuum advance. You have other problems namely points, wires, plugs. The car will cruise better, get better mileage, and live longer with a vacuum advance but the piss poor performance problem you are describing is elsewhere.

 

[Turboomni]

Now that you mention that 70bigblock when my 440's vacuum canister was bad the general area I noticed poor performance was at idle because of the vacuum leak. When it was cruising around I didn't notice it but I generally don't hammer the thing often. After the canister fix I had a much better idle and it was abit more peppy off idle.

 

[70bigblockdodge]

Now that you mention that 70bigblock when my 440's vacuum canister was bad the general area I noticed poor performance was at idle because of the vacuum leak. When it was cruising around I didn't notice it but I generally don't hammer the thing often. After the canister fix I had a much better idle and it was abit more peppy off idle.

Yes he has more/other ignition issues. Most dedicated drag cars don't even bother to hook it up and they run fine. It only comes into play at part throttle cruise to ignite the flame front earlier because of the further apart fuel molecules along with the less available oxygen molecules.

 

[Ripinator]

I'm scouring the interwebs looking for a good working canister replacement. I'm looking at NOS units mostly. I don't want a poorly made chinese built unit that's gonna fail in a month.. I'd rather buy an inexpensive, used, quality, functioning unit!

I'm a bit overwhelmed with all the technical information I'm getting regarding the order in which to do diagnostics/troubleshooting, tuning, timing, etc..

My plan is to:

-replace the vacuum advance
-check spark plugs and wires
-vacuum check entire system for leaks
-compression test
-check/set timing
-get & set new points and condenser
-check/set dwell
-replace ignition coil
-replace ballast resistor
-adjust carburetor once timing is intially and totally set
-drive car
-tune carburetor & ignition more
-drive car
-continue to tune & adjust timing with carburetor until she drives smooth as silk and with good power at any rpm.
-learn how to do all of the above.

I've still got to buy the following tools to accomplish it all:

-a dwell meter
-a timing light/gun
-a set of good feeler gauges
-a vacuum gauge(mityvac hand pump?)
-patience

-or just find a good mechanic locally and roll the car to their garage.

Your to-do list is rather comprehensive and all, but if I were you, I would just start with replacing the points and condenser, the rotor and cap, the plug wires and replace the plugs (I use AutoLite P85s). I just finished a similar tuneup on my '66 440, and the car now runs very well - no stumbling or missing, etc.

 

[GG-1]

Don't know about non metallic etc. There is no electricity going anywhere when I set the points.
There are alot of vids on you tube about it and dwell meters. Don't be alarmed,,guys have been doing this for one hundred years.

Sorry, I meant non-magnetic!

 

[Big_John]

Food for thought:

By the time you buy a new vacuum advance, points, condenser, cap, rotor and a dwell meter, you could buy one of these and be done with it.

MOPAR: 440 Hi-Rev Electronic Ignition Conversion Kit OEM Specs Charger Plymouth+

I can't remember if this was a 383 or 440. Just stay away from the Proform crap.

 

[GG-1]

Your to-do list is rather comprehensive and all, but if I were you, I would just start with replacing the points and condenser, the rotor and cap, the plug wires and replace the plugs (I use AutoLite P85s). I just finished a similar tuneup on my '66 440, and the car now runs very well - no stumbling or missing, etc.

Thanks. I replaced all of those things within the last year.. maybe poor quality parts, incorrectly installed, gapped wrong, etc.. idk. And during that time she's only been driven about 1000 yards total because of the poor running condition. I've run her at idle each month for 30 minutes just to keep things flowing/coated.
I'm actually starting to think that the original cap, rotar, points, plugs, and plug wires were all perfectly fine when I first got her.. and that I hastily dumped all that good factory stuff just because I didn't know any better.. just because "it's what you do". It's a 14,000 mile car that drove to church every Sunday for a couple of years. That's it.
So moving forward, I'm willing to check replace the things you mention again first and go from there... which means checking timing and dwell too. There's always a possibility that the carburetor was not rebuilt correctly.. float set? accelerator pump issue? It hasn't run right since I got it back from the carb rebuilders, but then again it was not running right to begin with.

A vacuum issue is still a primary suspect. I just gotta plug away. There is a huge learning curve in running full diagnostics myself, and I'm willing. I'm very appreciative of all efforts put forth by you guys to help!

 

[GG-1]

Food for thought:

By the time you buy a new vacuum advance, points, condenser, cap, rotor and a dwell meter, you could buy one of these and be done with it.

MOPAR: 440 Hi-Rev Electronic Ignition Conversion Kit OEM Specs Charger Plymouth+

I can't remember if this was a 383 or 440. Just stay away from the Proform crap.

Thanks for the suggestion and link.. and warning about proform. I've definitely gotta look into all that more.
I've got a 383 Commando 4bbl
For now I'd like to keep her original 100% while I get things dialed in stock.. and then maybe think about modifications or "upgrades"