Points/Plugs mileage

J

jgusgann

Junior Member
Was wondering what a good rule of thumb was for changing Points/plugs/ oil?? I drive my A a lot- couple hundred miles a weekend often.


Also, are the contacts on the points "hardened" metal? And if so, if I file my points down to dress them up(filing off the burned/pitted areas), am I filing off the "hardness"??


Also, what is a good engine oil weight?
 
Points should be changes when pitted or burned, there is no set mileage.

I change out the spark plugs (regardless of vehicle) when the spark is visibly week (Yellow spark), damaged electrode or a damaged insulator. Be sure to check the coil spark, it should be Blue, if not your coil is likely on it's way out.

Oil, ... when it feels gritty, dark in color, contaminated with water, smells bad or looks like Grey metallic paint. The current oil is miles ahead of what these cars were designed for so it's not really an issue at all. Some say, 500 and some say 3000 miles and some strecth it well past that.

Regards
Bill
 
Points and spark plug replacement depend on to many variables.

I would not file points. I would clean and check gap on plugs every 1,500 miles or so. This again would depend on engine and driving conditions.

Oil! That is something you very well will see a lot of different views on.

We use 20-50 HD Walmart oil, change once a year or 500 miles. Also use a bottle of STP blue as that last 1/2 quart. MMO in gas.

I don’t mind spending $20.00 on our 89 year old car. We are all just care takers. Even if they go to our children or grandchildren. Why take a chance?

Our 29’s engine was rebuilt in the 40’s. Still running strong, no oil burn or smoke, compression in the mid 60’s all cylinders, no valve noise. I really try to take VERY GOOD care of her. Enjoy.
 
Point file or "spoon" file was used. Points will sometimes get a layer of skunge after a while and prevent good contact. A field expedient is to use a crisp banknote soaked in naptha or contact cleaner as a kind of very fine emery paper and draw it back and forth across closed point set.
 
When all cars on the road had points, the recommended tune-up mileage was 10,000. New points & plugs were installed at that time. Points are made of tungsten or platinum, very hard material. It doesn't hurt to file or sand them if you want. A lot depends on if the coil and condenser are matched to the system, after 85 years, who knows. Oil change also has variables, do you run a filter, etc. I run full-flow filters, 20-50 oil and change after 2-3,000 miles. If your engine was run many miles with non-detergent oil and you now use modern oil, change every 500 until the crud is cleaned out.
 
jgusgann said:
Was wondering what a good rule of thumb was for changing Points/plugs/ oil?? I drive my A a lot- couple hundred miles a weekend often.


Also, are the contacts on the points "hardened" metal? And if so, if I file my points down to dress them up(filing off the burned/pitted areas), am I filing off the "hardness"??


Also, what is a good engine oil weight?
Click to expand...



When you say 'change plugs', are you meaning to change plugs in use with NEW plugs ?


New plugs are expensive. Most don't drive a Model A , in good condition, enough to wear out/ruin a good set of plugs.
And, if one's engine is not so good condition and say, burns a little oil, the plugs can get 'dirty/carboned' up. But, IMO, that is not reason to buy new plugs every time...'changed'.


Most plugs are good for a VERY long time. If dirty with carbon/oil, clean them with a spark plug abrasion/air cleaner and BLOW THEM CLEAN OF CLEANER. They can then replace your currently used set when wanted. Clean an extra set to carry with in repair kit and trade them off when you like. I keep many sets of differing heat ranges and use what the engine indicates is best when tuning. CHEAP harbor freight plug cleaning kit can be had. That's what I've used forever....even from places like JC Witney, before HF ever existed. Back when my cars used more oil than gas, it seemed, plugs fouled out quickly/regularly...so extra clean sets carried with were important.


Another very important spark plug maintenance aspect, is to run engine with proper thermostat. An engine constantly run COLD will not like what you are doing to it..and its plugs !
When should plugs be changed / discarded ? When porcelain around center electrode is badly burned and/or cracked chiped, when electrode(s) are burned badly/broken; when top porcelain is cracked and when you have tooo much $ burning holes in pocket and/or see a new fangled dudad plug with six ground electrodes...I'm a sucker for these !!


If you do decide to FILE points, learn how to do it and have right file for job.
Otherwise maybe create more problem than solved.


Oil is off limits, eh (yellow face).
 
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If using modern points, you can get platinum or tungsten for longer life. Little more expensive but good.
 
Original points are tungsten, the owners instruction book says never file points, use oil stone, now we have cheap diamond "stones"that work wonderful

So Far I have over 40 years on the reproduction 3X plugs, same points that came with car, and over 25 years on the A&L condenser, I rotated the center core of the spark plug 1/3 a turn a while ago, I keep good mixture control, tested it with emissions machine under load to know best gav adjustment, use point lube on smooth original B dist cam,

I think many here change their points just about when the rubbing block is worn in to where the adjustment stays good a long time,
 
I've never replaced plugs as often as manufacturers recommend - no need to for obvious reasons. Points: rarely, when there is virtually no tungsten left on them and as for oil, Do you have a filter? Do you use detergent oil? If yes to both, I change at about 2,000 miles for short (under 200 miles at a time) running and for long trips, (over say, 1,000 miles) I watch my speedo, oil pressure (I run a pressurised middle main bearing) and temperature. When the oil is at the end of its life, the pressure starts to drop for a given speed and temp. With the cheapest of cheap oil, that happens at about 3,500-4,000 miles.
 
I ran the inexpensive Autolite plugs & as long as it runs GOOD, I never even LOOK at them. Driving with "GUSTO" helps keep them burning clean. LOOOOONG idling sessions crap them up!
Bill Runninglikeasewingmachine (SINGER!)
 
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