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Subject: Which up-dated spark plugs for my 8n?

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Jeff in Maine    Posted 10-03-2020 at 19:48:45 [URL] [DELETE]        [Reply] [Email]  
  • Which up-dated spark plugs for my 8n?
  • For my 1951 "Babe" I got a very late start this season. She sat idle for a full year. I reconnected the battery, charged it and after checking for spark (good)because she would not start I siphoned all the Sta-bilized gas out and replaced with fresh, non-ethanol gas and cleaned the richly carbonized plugs, and she did start and ran smoothly for a 15 minute test. Two hours later she wouldn't start. Went to local NAPA for new plugs as I have done every season, for the Champion H12's but they were out of stock. Asked for the Autolite 437's but NAPA didn't recognize that number (huh?). The clerk offered AL 216 which he said was compatible. Bought'em but checked on line, found that there are 3 AL plugs said to be compatible. The AL webpage says that the end number, 6 in this case, indicates heat range, and the higher the number the hotter the plug. I could not confirm if that is the same with the Champion H12--but if so, that's quite a jump from 2 to 6, which would be a step down from a 437? I have not installed the 216's yet, pending Forum replies.
    BRUCE, are you out there??

    Maybe the AL 216 copper plugs are a newer version of the 437's??
    P.S. Regrettably am relocating so will put Babe up for sale once I get her back to speed. (sigh)

    Jack - Iowa    Posted 10-05-2020 at 07:54:06 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Which up-dated spark plugs for my 8n?
  • This was copied from another source: Does a good job of explaining the difference.

    We recommend the HOTTER AutoLite 437s' gapped 0.025" for todays un-leaded fuel that FOUL the cooler H-10 or 216's. As you discovered, the 437's ceramic nose is LONGER, why? 'cuz the LONGER the thermal path to the cooler cylinder head the HOTTER the sparkie which then BURNS the oil and lead deposits from between the gap.

    Lynn Patrick    Posted 10-04-2020 at 07:51:14 [URL] [DELETE]        [Reply] [Email]  
  • Re: Which up-dated spark plugs for my 8n?
  • I prefer the NGKs.

    Bruce(VA)    Posted 10-04-2020 at 07:24:08 [URL] [DELETE]        [Reply] [Email]  
  • Re: Which up-dated spark plugs for my 8n?
  • Congratulations.

    You have confirmed that even when you give them a part number, many parts clerks are clueless as to the basic functioning of the part.

    You need a hotter heat range plug in the tractor because it is not used on a daily basis.

    That would be a Champion H-12 or Autolite 437.

    ANY plug in that heat range will work better than ANY plug in the colder heat range of the H-10 or........the 216.

    You can get the 437's at Advance.

    You can also use the NGK B4L plug.

    NGK 3112 (B-4L)




    Tim Daley(MI)    Posted 10-04-2020 at 06:28:52 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Which up-dated spark plugs for my 8n?
  • When it wouldn't start agin, did you test the battery static? If good, did you check for spark right after it wouldn't start up again? When you pull a plug, is it fouled or dry? Do a fuel flow test when engine is cold as well. Running for 15 minutes may have sloshed around some debris in which to plug up Sediment Bulb. Here's the skinny on spark plugs: OEM FORD TRACTOR specs plugs at 14mm CHAMPION H10. Years later they came out with the H12 style which was hotter plug. The AUTO-LITE 437 was released as well and was also a hotter plug. ALL 3 Plugs will work on your tractor. Now, 10/20 years ago the powers that be, in their infinite wisdom, decided to change up model numbers. The Champion H12 is also numbered as 512, and the AUTO-LITE 437 is now listed as 216 and they are all one and the same respectively. Also important: Did you simply apply a 'charge' to your old existing battery when first starting up after not running for a year or more? If so, chances are good it is a weak or dying battery and no amount of charging is going to fix that. Did you keep your battery on a float charger when it wasn't being used? A battery that sits idle for a few weeks, more than 30 days, will start to deplete electrolyte and lose the specific gravity and thus deteriorate the lead plates. This is the worse thing for battery life; the constant discharging and recharging. The cure for this is to invest in a Float Charger (NOT a trickle charger) to keep the battery connected at all times so it is fully charged and ready to go when needed. The DELTRAN Battery Tender Jr. is the 6V model and is well worth the $30 investment.`Also, FWIW & FYI, fuel additives like STABIL are nothing more than plain Mineral Spirits, the same stuff as charcoal lighter fluid and paint thinner, and will thin out the gas so it's up to you if you want to spend your $$$ on those products.

    You need a strong battery to:
    1. Spin the starter
    2. Engage the Bendix
    3. Provide voltage to the coil.

    The following is courtesy of Bruce(VA), tips on battery care and performance:
    As the battery gets weaker, the first thing to fail is your spark. The more current you use to spin the starter, the less you have for the ignition. If your starter pulls that battery down much below 5.2 volts (ref: 6-volt battery), the module in the EI will not fire. It doesn't really matter much if the battery is "fully charged" until you test it correctly. 4 Volts is an almost dead unit. Bench test under load and specific gravity must be tested. Your trusty local starter/alternator shop can bench test it on their special machine, usually at no charge –no pun intended. No matter what else you do, the battery must be fully charged first.

    A float charger is helpful; not a trickle charger, but a float charger, like the DELTRAN Battery Tender Jr. ® ™ , a popular brand, available at Walmart. A battery charger, even a "trickle" charger, left unattended will eventually boil out a battery. Use a float charger for two reasons: battery longevity and a sure start. Battery sulfation occurs at a specific rate at "X" temperature. Over time, sulfation reduces battery performance and eventually its effects are irreversible. Sulfation of batteries starts when specific gravity falls below 1.225 or voltage measures less than 12.4 for a 12v battery, or 6.2 for a 6 volt battery. Sulfation hardens on the battery plates reducing and eventually destroying the ability of the battery to generate current. Using a float charger significantly reduces sulfation. Your battery loses 33 percent of its power when the temperature dips below freezing, and over 50 percent of its power when the temperature falls below zero. A fully charged battery will not freeze until -76°F; however, a fully discharged battery can start to freeze at 32°F. So……keep the battery fully charged! If you have a digital volt meter, 6.03 volts on a 6 volt battery and 12.06 volts on a 12 volt battery is only a 25% charge!


    Tim Daley(MI)

    Jeff in Maine    Posted 10-04-2020 at 20:29:58 [URL] [DELETE]        [Reply] [Email]  
  • Re: Which up-dated spark plugs for my 8n?
  • I didn't get back to work on Babe today, will try tomorrow. Meanwhile, after charging I disconnected the charger and the the battery cranked the engine strongly. Yes, for a full year the battery was disconnected but not on any charge. I haven't yet looked at the electrolyte but will do. The sediment bulb remained clear after I drained the tank, and initially the flow was slight to nil but afterI put in approx. 2 gallons (which I recall reading by someone on the Forum (Bruce?)is the minimum to get a good flow to the carb, and that did work. Here in coastal Maine the winter temps may not get quite as low as in Michigan but below freezing is common and last winter was the coldest winter in 10 years. I'll pull the plugs again, and expect that as usual with Babe her plugs may will again be heavily "carbonated" from running rich, although she only ran 15 min. or so.(I never seem to have been able to counter act that.)
    Question: If 6.03v is only a 25% charge, what is the desired rating??

    BRUCE: TIM says the AL 216 is in fact the same as the 437. Agreed?

    Thanks all, I'll report back ASAP.

    Jeff in Maine    Posted 10-05-2020 at 12:18:00 [URL] [DELETE]        [Reply] [Email]  
  • Re: Which up-dated spark plugs for my 8n?
  • Update: as there was still some confusion at least in my mind about the AL 437'S being re-numbered or similar but perhaps not with identical heat range to the 216's, I went to the source and spoke with an AL tech. The short answer is the heat range is identical, the only difference is the length in height of the electrode "projection". And for those out there who like me could make little sense of the heat range pdf that Bruce sent (also available at autolite.com), the 216's on line 15 of that chart are "short" projection, the 437's on line 16 (meaning, BTW, heat range) are "mid". And the AL tech confirmed that both are cross-compatible with Champion H-12's.
    So, I will put the 216's in and hope Babe comes back to life!

    Jack - Iowa    Posted 10-05-2020 at 21:35:40 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Which up-dated spark plugs for my 8n?
  • I can tell you from experience on a International truck, if you've got an oil burner that electrode projection makes all of the difference!

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