Well Old was right

grandpa Love · Jun 29, 2019

Talked with Old last night and I mentioned that I put new spark plugs in my Allis B. Auto lite. Looked through the archives and got a number for hotter plugs. Anyway , tractor went from starting on 1st or 2nd pull on crank to 15+ pulls. Ran fine, but hard to start. Old said put old plugs back in. They were champion. It started on 1st pull! Guy at O'REILLY'S said to bring em back, probably bad plugs. He also said I could test with a multi meter. How? What do I set it on ?

SVcummins · Jun 29, 2019

Set it on ohms the one that looks like a horseshoe

guido · Jun 29, 2019

Hello grandpa love,

The short answer in you can not! Next time I get a perfectly tested ohms plug, i'll save it for show and tell. I tossed the las tone out that was Not shorted to ground, the right ohms readings, and dead as a door nail once installed in the engine. New plug and all was well!

Guido.

SkipperII · Jun 29, 2019

Many moons ago,I tuned up a Dodge digger/derrick, at the power company. The next morning, it wouldn't start for the crew. Got called in to check it, nope wouldn't start. Had to put the crew into a spare truck. Checked fuel flows, dwell, spark, timing, camshaft timing. Pulled the plugs, good blue spark. My boss came in, said, well; Grab another set of pts. cond, rotor, cap, wires, and start replacing them. Nothing worked, replaced the Champion plugs with Autolites, fired right up.

Jaden · Jun 29, 2019

Testing a spark plug with an ohmmeter will only find some problems. The ohmmeter only uses a 9 volt battery, which will not show problems with a several thousand volt spark from a good coil.

old · Jun 29, 2019

As I said find the cross over for NGK plugs and you will find you have easy starts

rustred · Jun 29, 2019

why don't you plug each one into one plug wire one at a time and run the tractor. you can watch the plug firing if it does and see how the spark is. perfect test. plus who said champions don't work. that's the only plug I buy.

Steve@Advance · Jun 29, 2019

Supposedly you can test then with an ohm meter.

You would set the meter on the 20k setting, a new plug would read around 1000 to 8000 ohms.

That's a wide range, but the high voltage should have no trouble making the jump.

To test, put one lead on the top terminal, reach in and touch the center electrode tip only with the other lead. That should give the 1000-8000 reading. Then set the meter to a low setting or continuity setting. Check from the top terminal to the base. Should get open, no conductivity.

Interesting theory on resistor plugs. I always though it was only for radio noise, but there is another reason. It gives a hotter, more definite spark. Check out the 5th topic about low resistance. I realize this is about aircraft shielded plugs, but still the same theory.
Plug Testing

rustyfarmall · Jun 30, 2019

Allis B with a hand crank most likely is equipped with a magneto. Magneto ignition requires NON-resistor type spark plugs. If the NGK plugs you bought were of the RESISTOR variety, that is where the hard starting comes from. The Champion D14, D16, D18, etc. are all non-resistor plugs.

grandpa Love · Jun 30, 2019

Archives recommend autolite 295. I
wasn't a fan of em! Lol.

Bret4207 · Jun 30, 2019

(quoted from post at 00:20:27 06/30/19) why don't you plug each one into one plug wire one at a time and run the tractor. you can watch the plug firing if it does and see how the spark is. perfect test. plus who said champions don't work. that's the only plug I buy.

I gave up on Champion years ago after buying 8 and finding 5 that were bad right out of the box. When the center electrode will slide down into the plug when held upside down, that's a bad plug.

Leroy · Jun 30, 2019

When you put in new Champion of model called for in morning, have to take out and clean at noon to keep on working, next morning start repeating for a week and you change to different brand, at that time it was TSC's own brand and did not have to touch them for 2 rears you believe that brand is bad never to buy again. And this was working under heavy load, not idling. And if you went back out in evening you had to clean those Champions again to get any work done.

sotxbill · Jun 30, 2019

I have several old AC sparkplug testers...
that test under compression...

And usually I find one out of four bad. They will not fire at the rated compression for the gap set.. which is about 120 lbs for .035 In my motorcycle collection this is critical as they run very high compression. On my lawn mowers, not so critical. On tractors, somewhat critical. NGKs almost always test perfect, even used. autolite, champion and ac, not so much.
Since most are now made in china, bad plugs are much more common. In the 1970s I had a high compression engine and using the same kind of tester for 160 lbs, ac plugs always tested perfect, motocraft-autolite next, and champion were last,, but again that was testing at 160 lbs with american made plugs.

However once you get a good set of plugs, they tend to mechanically stay good... clean 'em, check gap, and back in business. Yes they can oil foul, but a good cleaning puts them right back.

pete 23 · Jun 30, 2019

Now that is a truly defective champion plug.

Well Old was right

grandpa Love

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SVcummins

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guido

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SkipperII

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Jaden

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old

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rustred

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Steve@Advance

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rustyfarmall

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grandpa Love

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Bret4207

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Leroy

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sotxbill

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pete 23

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