I found out today that the mechanical advance, on my 225 with electronic ignition, isn't working.
I was trying to set the timing and the vacuumadvance works like a charme, advancing the timing some 20-25 crankdegrees. When I disconnected the vacuum, the mechanical wasn't advancing at all, not even at 3500rpm.
I took out the distributor and partly dissassembled it. I could twist the mechanical advance by hand, but that took some effort. When releasing the shaft it turned back to its initial position.

What could be the problem, and how can I fix this?

At what rpm should the mechanical advance be totally in?

Thanks,

Antoon

_________________
suffering from severe moparitis

I set "street car" distributors so the light advance spring allows mechanical to start 3-400 RPMs above your curb idle setting. (1200-1400 RPM range)
Set a looped heavy spring to "catch" the weiights and slow down the advance rate, for the last 4 to 6 degrees.
Set the total at 30 degrees, at your typical "running fast" highway RPM. (2800 to 3000)
DD

Antoon

1970 Challenger, right? Got points or has it been up-graded to electronic ignition?

Have you gotten a copy of the “Factory Service Manualâ€￾ yet? This distributor service sequence is fully outlined in that publication for your viewing pleasure.

I’m assuming that it hasn’t yet arrived, so here is what you have to do to free up the governor’s weights so that they will do their job.

First make note as where the rotor button is pointing, mark it somehow, so when it is time to reinstall you can get it exactly where it was, and than remove the distributor from the engine.

You will have to disassemble the distributor by removing: points or electronic pick-up; breaker plate (the thing point or pick-up are bolted to); the little felt in center of shaft; Vacuum can; a “Câ€￾ shaped spring clip locking the cam & slotted guide onto the shaft under that felt (this clip can be extremely reluctant to give up its grip, but two small screw drivers & needle nosed pliers will win the day).

If electronic, remove reluctor (that six bladed thing on the shaft) by placing two large screw drivers under it and forcing the reluctor up the shaft until it comes off. This may or may not go easily depending how corroded things are. The reluctor is indexed by a small roll pin, don’t loose it. Than remove the "C" clip under the felt.

It is important to mark or index the slotted shaft so it is placed back in the same position as when you removed it from the shaft. If you don’t get this right, the engine will be 180 degrees out of time, and will not start.

Once the slotted bar is out, clean all moving parts of the weights & their pivot points so as to allow them to move easily, than lubricate all moving parts of the governor (weights), and reassemble all the parts. Also check the springs for damage, and replace if needed.

Apply a few drops of engine oil to the felt, and a light coating of grease, or Vaseline to the cam if you have points, and set the gap 0.017" to 0.023".

If you have electronic ignition, set the gap between the reluctor & pick-up at 0.007â€￾. Check all six gaps, and if needed, average them as close to 0.007-0.008â€￾ as possible, than hand spin the shaft to make sure nothing is hitting.

Generally speaking mechanical advance should be all in by 2800 rpm or so, within 3* of full in at around 2400 rpm or so. Your car may be set up differently depending on any performance modifications.

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Thanks for your elaborate advise.

It's for my 68 valiant 225 however (updated tp electronic ignition). I allready took the dizzy apart, and I could move the weights fairly easily, and they also returned in there resting position as well, nothing seems to be stuck.

I opened up another dizzy I've got lying around, which has more mechanical advance build into it, and serviced that to go in to the valiant tomorrow.

What could cause the mechanical advance not working, other than stuck weights?

Thanks,

Antoon

_________________
suffering from severe moparitis

Antoon,

Sometimes the old grease gets too hard and binds on the shafts or a little moisture over the years will cause rust on the shafts. I would use some emery cloth, scotch pad, etc....and really clean up the posts and clean out the weights. Use synthetic oil on reassembly. If they won't fling out rotating the shaft between your palms/hands, you need to do some more cleaning.........The weights should freely swing out with out binding.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Antoon:
[quote]What could cause the mechanical advance not working, other than stuck weights?[/quote]

The braker plate could be distorted causing a bind, vacuum can arm may be causing a bind, or as Ted said; “she ain’t shinny enough yetâ€￾.

Bill

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Ok thanks,

I'll take it out and give it a good cleaning.

Thanks for the tips

Antoon

_________________
suffering from severe moparitis

Ok,

Here it is.
I took the distributor apart and cleaned it. There was indeed some old grease which made it go not so smooth.
The advance-rate that was engraved in the plate was only 9 degrees. Isn't that a little low? The distributor had a casting date of 1978.
I had a spare distributor lying around with an advance rate of 15 degrees.
So I used that shaft, and and the rest of the distributor I started with, including a 7,5 degrees vacuum canister.

After cleaning, greasing and adjusting I installed it, set initial timing to 5 degrees before tdc, and fired her up.

She started up immediately. total timing, including vacuum was now around 40 degrees at 2500.
I would like to get it a little more, as I read in mopar action that a slant six likes it around 50 to get a good MPG.

Although the advance rate on the distributor shaft says 15 degrees, it doesn't make that amount, well actually it does get 15 crank degrees, but doesn't the 15 degrees on the shaft be cam degrees, so it makes 30 crank degrees?

A lot of questions, but I'd like to get it right with gas prices of around 8,5$ per gallon

Thanks,

Antoon

_________________
suffering from severe moparitis

The 9° governor which limits the mechanical advance is usually a good choice. It allows more initial advance without over advancing at high engine speeds. The 15° governor will give you 30° advance at the crank and is for smog engines which have the initial timing set at TDC. Total initial and mechanical advance should only be 28-30°. You can usually add whatever vacuum advance you can on top of that. The only caveat is if the dynamic compression ratio is too low you can end up with too much advance and suffer a power loss without ever getting into detonation (ping).

_________________
Joshua

with the 15 degree governor, at 2500 I'm getting about 25 degrees advance, with an initial timing of 5 advance, so I'm missing 10 degrees somewhere.

Antoon

_________________
suffering from severe moparitis

You must have a pretty stiff with a short loop secondary spring. A lighter set of springs will provide more unless there is some binding.

You don't really want a lot of mechanical like Josh mentioned. The reason being is that engine can go flat with too much timing.
The SL6 is spunkier and runs better with more initial advance. If you can run it at 10 degrees or more you will notice the sluggishness goes away. As an experiment, I have run as high as 20 degrees initial and only 10 degrees of mechanical and 22 degrees vacuum advance. I prefer to keep it under 16, most of the time it stays at 12 degrees initial and about 20 degrees mechanical for the weight of my car 3300 lbs running regular gas.
It is a balance between the three forms of advance to compliment the gear ratio, tire size, weight of the car or truck, drag, etc.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

I thought that the stock slant six should have around 2 degrees initial. At least the ones before 77, and that they later changed that to around 12 degrees advance?
I think I'll drive it as it is right now, and pay attention to detonation, and gas mileage.

By the way, I haven't changed the springs on the governor assembly, so they are the stock ones for that dizzy.

What would be a good total advance setting be? According to the E-booger, even 50 degrees is acceptable?

Thanks,

Antoon

_________________
suffering from severe moparitis

The term "total advance" is for the initial + mechanical advance... it does not include the vacuum advance. For a SL6, that should be 30 degrees, vacuum advance disconnected and the engine revved-up.
With vacuum advance connected, at light throttle, 45 to 55 degrees of advance is acceptable, as long as these is no detonation.
Note, when you apply throttle at speed, (manifold vacuum drops) the vacuum advance "comes-out" or goes to zero at full throttle.
DD

Ok Thanks,

It seems I'm at about 30 degrees right now @3000 rpm, so I think it's about right.

Thanks for all the help.

Antoon

_________________
suffering from severe moparitis