Plugs for '47 H

[old popper]

Being a mostly 2 cyl John Deere man, I would like to know what brand, and what number spark plugs you fellas would recommend for my Farmall H. It burns a little oil, but not much. I started it today for the first time this spring, to change the oil and it was min firing on #2. The plugs that are in it have a pretty good coat of red paint, so I came to the experts. Thanks, in advance.

 

[Bob M]

I've had excellent luck with NGK #AB-6. In stock for about $3 apiece at most autoparts store.

 

[rustred]

put some champion 15y's in it. they are a longer reach and hotter plug.

 

[J Hamilton]

Autolite 3116 would be my choice

 

[rustyfarmall]

(quoted from post at 20:31:14 04/19/20) Autolite 3116 would be my choice

My choice also, but after sitting for awhile, the mis-firing MIGHT be due to a stuck valve.

 

[roy prins]

Hey old Popper-- I use D21 champions in just about everything except a plow tractor-- then they are a little to hot -- then I go down to a D18 -- Roy

 

[jhncp]

Disy's

 

[old popper]

Thanks to all who responded. I was in town this AM and picked up the autolite 3116 plugs. I keep my tractors at my brother's place, and my old dog and I went out and installed them a while ago, and it starts and runs like a top.
Thanks again for your help.

 

[DR. EVIL]

The "standard" plug for decades was a Champion D-16, so the D-15Y is actually slightly cooler than the original D-16, but the extended tip on the D-15Y puts the spark down further into the combustion chamber which makes it easier for it to ignite the fuel/air mixture. The D-15Y's in my Super H I installed back in the 1980's, it idles around all winter pushing snow, and idling with no load when I come in the house to warm up.
The D-21 is WAY too hot even for an H mowing hay with a sickle mower. Not a fan of Autolite plugs, they make Motorcraft plugs and one of the factory installed Motorcraft plugs in my '87 F-150 had a BIG chunk out of the porcelain insulator around the center electrode when I put new Champion plugs in it at 10,000 miles. It probably bounced around and broke up into tiny pieces before being blown out the exh valve. I'd use an NGK plug but NEVER an Autolite.

 

[rustred]

ya I see what your saying about slightly cooler. I know they were a recommended plug for these tractors. have them n my case dc4 also. I am not a fan of autolite either. they are a cheaper built plug and have seen more problems with them than champion. guess a rumor gets started and it keeps on going. I do know when the autolite threads get siezed the plug will twist off due to thinner metal. the champion has thicker metal at the threads. experienced that also.

 

[DR. EVIL]

Only problem I ever had with a Champion plug was my spark plug socket would stick in the recess in the head of the H/SH, and then if you wiggled the socket to get it loose you busted the top porcelain end of the plug off. I fished the rubber insert out of the socket and problem over.
Dad sold a rather new to him stage 1 Super M to a young farmer, wanted the SM as a chore tractor. Dad gave it a good tune-up, checked spark plug gap in the D-16 Champion plugs that were in it, set points gap, put his tach/dwell meter on it, checked timing, everything checked out. Ran like a sewing machine. Month or two later the guy calls, SM wouldn't start. Dad grabbed his Doctor's bag of tune-up tools, guy points to the machine shed the SM was in. ALL new AC plugs, cheap resistor core Farm & Fleet plug wires, cheap F&F distributor Cap& rotor. Dad goes into the IH dealer in town that just happened to be right next to F&F, buys all new tune-up parts to replace everything the young guy had replaced, installed them, Champion plugs, not AC, SM popped right off, Dad goes up to the house, bangs on the door, tells the guy, The parts to replace what YOU installed cost me this much to replace, I'll take cash or check, my labor is free first time ONLY. Dad had learned that lesson the hard way 4-5 years before, He bought AC plugs for his '51 M, it would start but run poorly. He needed to grind cattle feed. He hunted up an old set of Champion D-16's I'd put 250 hours on in my '39 H. Mouse nests, dirt, chaff in the coffee can, He cleaned them up good, M started ran good, Dad put another 250 hours on those used plugs.

When I started driving, running equipment, cars/trucks were supposed to run 10,000 miles on plugs and points. Now days the Iridium plugs used in spark engines are much more expensive, but last 100,000 miles. They sometimes seize in the cylinder heads. Not even any points & condensors to change, just a coil on the spark plug.

One thing I really regret is letting Dad's doctor bag of tune-up tools get away from me at his last auction in 2006. It probably sold for $5-$10, timing light, tach/ dwell meter, distributor wrenches, a flexible GM dwell adjusting allen wrench tool, feeler gauges, points rubbing block grease.