Greg Armstrong
Well-known member
I just put a set of AL 3116's in last night and it fired right up in the cold and ran great while plowing the lane. I had fouled NGK AB-6 plugs that were too cold.
D21 spark plug Help
- Thread starter Command52
- Start date
outdoors4evr
501 Club
I don't understand the Normal, Severe, Intermediate service types in the chart above.
The Manual shows D16 as Light, and D21 as Severe.
I'm guessing that mowing and pulling a breaking plow would be severe service?
I've run Autolite 3116, Champion D21, and am now running the NGK AB-6 (only a couple of months on these)
The Manual shows D16 as Light, and D21 as Severe.
I'm guessing that mowing and pulling a breaking plow would be severe service?
I've run Autolite 3116, Champion D21, and am now running the NGK AB-6 (only a couple of months on these)
Which manual are you looking at? This agrees with GSS-1356 Engine Tune-up Specifications (pages 6, 7).
Yeah, I was kind of waiting for somebody to call me out of that little "spark plug helper chart" I made. LOL.
I skimmed through a bunch of Cub service manuals that i found here from a full range of years ( 47-79 ). Of course some part numbers and descriptions about the "duty" you are running your Cub at never changed, other times it did. I took snippets/screen shots and compiled them on to one pic ( jpeg), but it was just too big to post. I tired going to the Champion web site, and Autolite, but sometimes it seems the plugs were listed because they "fit" the C-60 engine, and not because they were in the same "heat range". So I decide to use MS Excel and make a little helper chart so my old brain could read it. Well, I had to compromise on some lines, but it at least gave me an idea of the Autolite plug number that comes close to whatever Champion plug the old manuals called for back in those days.
I left out the info for Prestolite 18R52 and AC-87 (C87), and didn't try to add NGK at all.
Not perfect, but....there ya go.
RedCub
I skimmed through a bunch of Cub service manuals that i found here from a full range of years ( 47-79 ). Of course some part numbers and descriptions about the "duty" you are running your Cub at never changed, other times it did. I took snippets/screen shots and compiled them on to one pic ( jpeg), but it was just too big to post. I tired going to the Champion web site, and Autolite, but sometimes it seems the plugs were listed because they "fit" the C-60 engine, and not because they were in the same "heat range". So I decide to use MS Excel and make a little helper chart so my old brain could read it. Well, I had to compromise on some lines, but it at least gave me an idea of the Autolite plug number that comes close to whatever Champion plug the old manuals called for back in those days.
I left out the info for Prestolite 18R52 and AC-87 (C87), and didn't try to add NGK at all.
Not perfect, but....there ya go.
RedCub
Gary Dotson
501 Club
Hey, I like it, saved it to my desk-top.
Quite a few options and opinions here on the best plug to run in a Cub. I just picked up a 1952 Cub a couple weeks ago that had been sitting for quite awhile. Been greasing and changing fluids and working on 6V charging system. It fired right up after flushing old gas out and cleaning under dist. cap. Runs smooth on the old champion D-15Y plugs that are in it. LOL, they look like they are rusted in there, the whole plug is rust, so I was looking to find the correct replacement size. Been spraying around them with PB blaster hoping they come out ok.