|
By PF Arcand - 16 Years Ago
|
Since distributors are the recent hot topic, here's my problem. It's a 57 or later NAPA (semi) rebuilt, installed 2 years or so ago, but much later I checked the dwell & found it under spec. Reset points, still well under the 26 degrees minimum specified. When I inquired here some time ago, was advised (by John "H" as I recall) that the Distributor cam is probably worn. Left it over the winter, did a recheck & discovered that if I accelerate the engine the dwell is also moving 2 or 3 degrees. Does that indicate that the advance plate is also defective? Are parts available for these distributors? I have a 55-56 distributor here, can I mic the 2 cams as a possible check, & also may have access to a 317 dist. to check. Are the cams the same? I'm sure some one is going to recommend an after market MSD or other unit, but, my car is licensed & insured (at a discount) on a stock collector plate. Obvious mods are not permitted, except safety items such as brakes & light improvements. I don't see any point in getting another NAPA (Canada) unit. What are my options? Any info appreciated, thanks
|
|
By Glen Henderson - 16 Years Ago
|
|
First of all, how does the engine run? Are you having specific problems? I have a dist machine and have ran several distributors on it and they all have variances. When I worked at dealerships back in the 60's/70's, we always set the points by dwell when doing a tuneup. If you are familier with the Delco dist of the day that had a window for external adjustment, they were adjusted with a dwell meter. If the engine is running and starting fine, I would not be overly concerned, just adjust the points to get the proper dwell.
|
|
By Hoosier Hurricane - 16 Years Ago
|
|
Paul: Distributors later than '58 have the point plate mounted on a stud and they pivot in an arc when the vacuum advance pulls them. This will obviously change the dwell since the points gap changes. The '57-'58 distributors have a ball bearing point plate that rotates about the center of the distributor shaft, so no change in gap. I know, Thunderboy has big problems with point gaps in his distributor, but that unit has a problem not yet found. I don't know if the cams are all the same dimension. An electronic conversion such as pertronix would not be sensitive to a worn cam.
|
|
By PF Arcand - 16 Years Ago
|
|
Glen & John: Thanks. The engine has an inconsistent idle, sometimes o.k. other times not, which made me suspicious. However, it could also be somewhat carb related I suppose, it's an older 2 barrel 2300, which has given me some grief in the past. (mostly dirt related) The dwell hovers around 19 or 20 unless the engine is accelerated, then it moves to about 22-23 degrees. Isn't that low a dwell likely to cause misfiring under higher RPM? I've also played with the idle screws several times, it will seem o.k for a short while, then the bad idle returns. Currently they are set at about 2 turns out (Any more than that & the exhaust will make my eyes water) Oh! and another possibly related question. The filter for the carb is a clear Fram.(less than a thousand miles old) When the engine is idling, the filter shows a low gas level, not full. A friend suggested that's not normal. Yes or no? However, I have not noticed any indication of fuel starvation in normal driving. And Glen, are you indicating it's o.k. to open the points a bit more than the max 16 thousandths in the book?
|
|
By rick55 - 16 Years Ago
|
Reading your last post, you say your dwell is 19-20 at idle and 20-23 when accelerated.
The factory dwell setting should be 26-28 1/2 which equates to .014 - .016". Your points are set far too wide and this will affect your idle and general performance. Try closing them up to get the factory setting and see what your engine behaves like then. With the point gap too wide the coil may struggle to provide the required spark. The important setting of the dwell is at idle as it may change slightly when revved on some distributors though it should never vary by more than 2 degrees. If it moves around at idle that would suggest wear on the contact cam face or worn bearings in the distributor.
A rule of thumb is low dwell reading- wide points and vice versa.
Hope this helps.
Regards
|
|
By Glen Henderson - 16 Years Ago
|
|
Paul, Rick explained my thoughts on the subject very well, so I want go through it again. I will say that is is very hard too set the points with a filler gauge if they have any pitting at all. As they open the spark transfers material from one side of the contact too the other. This is why they require filing or replacement on a regular basis. One other comment if you have a vaccume gauge, use it too adjust the idle screws. John made a good comment in that the later dist's have some built in slop.
|
|
By DANIEL TINDER - 16 Years Ago
|
[quote][b]Glen Henderson (8/13/2009)
I will say that is is very hard too set the points with a filler gauge if they have any pitting at all. As they open the spark transfers material from one side of the contact too the other. This is why they require filing or replacement on a regular basis.
Glen,
I learned recently that metal transfer is only significant when the condenser value is not absolutely perfect for your specific engine/ignition resistance (a rare occurrence). And then, only the peaks should be filed, as no advantage results from filing the pitted point. If the condenser value IS correct, and the points are not burned or oil-fouled, the irregular surfaces actually INCREASE electrical efficiency.
|
|
By Ol'ford nut - 16 Years Ago
|
THE LOAD-O-MATIC DISTRIBUTOR By Gerry Dubois |  | | | The Load-o-Matic distributor is essentially the same from the bowl up on all modern Ford units. Take a '57 or later distributor, remove the breaker plate and upper shaft assembly. Replace these with the beaker plate and upper shaft assembly from any '75 or later Ford V-8 distributor. Install a new stator and reluctor. You will have to notch the distributor housing to fit the stators wire harness. This is as simple as extending the existing hole up to the rim of the bowl. The old style cap can be retained for an old time look or the new style two-piece cap can be used with modern 8mm wires for best performance. You will also need a module and a Duraspark unique coil. You could fab up a harness on your own or purchase one from a Ford industrial dealer.(Part number D7JL-12A200-CA) This harness will plug directly into the distributor, module and coil. It has two wires to power it. Luckily the brown wire and the red wire that now go to the resistor and the positive side of the coil are the correct input for the job. Make the two connections and turn the key. You may have to disconnect the brown wire from the starter relay to avoid a feed back that will cause the starter to run on after you release the key. You will want to regap the plugs to about .045" to take advantage of the much stronger spark. You can also use an MSD 6AL type of module with the Ford distributor, if you wish. MSD offers a harness (#8869) that plugs into the Duraspark distributor plug while the other end plugs into their module. Follow the MSD instructions for the rest of the wiring requirements. If you decide to go this route, be sure to use one of the MSD Blaster coils. An upgraded vacuum advance could give even more power. The local auto parts store usually carries these. I've used the '85 Mustang 5.0 replacement to great success. These are adjustable for the amount of vacuum it takes to bring in full vacuum advance using an 1/8" Allen wrench through the vacuum port. This particular unit offers 20 degrees of advance at the crank. The arm is marked with a "10". The fuel economy improvement is enormous. |
I take no credit. Found this on the web.
|
|
By PF Arcand - 16 Years Ago
|
|
Thanks everyone. I'll start by re checking the point gap. Thought I had it close, but maybe not.
|