sprk plugs

[Geer Pyron]

Does nyone know wht sprk plugs the ’37 fishermn uses?
nd source for the older style?
Mybe guide or reference chrt?
Certin key on my computer seems to be not working.
Thnks,
Geer

JMGP

[Buccaneer]

champion M6 according to the chart. I need to build myself a chart for
showing myself all the “replacement” plugs shown in these old charts.

Prepare to be boarded!

• This reply was modified 4 years ago by Mumbles.

[Buccaneer]

If Champion 6M is the same as M6, it looks like you could use the Champion D14

18mm spark plug heat range chart … Hottest on top, Coldest on bottom

Champion – – – AC – – – Autolite – Bosh – Motorcraft Prestolite
C7 (D23) – – – – – –
C15(D21) – – – C88 – – – – – – – – – – BT9
7 (D16) – – – C87 – – – – – – – – – – B8X
6M (D14) – – – C85 – – – 386
5M (D9) – – – C82 – – – 373 – – M8A – — – BT4 – – – 18-3
R7 (D6) – – – – – – 372 – – M7A
R1
R11
R11S Old racers using Alcohol
R2
R2S Using Nitromethane.

Prepare to be boarded!

[Mumbles]

The 1942 service manual says your motor uses a P/N 190724 Champion M6 plug gapped at .025″ but I think they meant 6M and not M6. A modern replacement would be a Champion D14.

https://www.sparkplug-crossreference.com/convert/CHAMP_PN/6M

https://aomci.org/forums/topic/champion-6-m-cross-reference-or-replacement/

• This reply was modified 4 years ago by Mumbles.

[labrador-guy]

Geer, I just picked these up at wallieworld! 18mm Autolight. Surprised to find them and a cheep price. Check.em out.

dale

$1.78 must be a mistake!

[Geer Pyron]

Ha!!!!
That’s what I got!
From The Wally-World too!
A friend says the ‘37 fisherman will take a Champion D14 too.
But it was black.
The auto lites are a nice brushed nickel.
Ha!!
Picky picky me.
But alas, spark plugs weren’t the problem.
Still not running after two mag plate rebuilds, two carb the aparts and put back together, new rings, and hours(?) of chin scratching.
It did pop and I think fired once. Made a popping sound.
I had to walk away from it today. Hard to do, but it’s the first time I’ve been really frustrated.
G

JMGP

[Geer Pyron]

I’m back at it today.
If any of you guys have any suggestions I’d love to hear them.
This what I’ve done.
Re built the mag plate with parts and help from a friend. Including ditching the two later style coil swap. New wires and plugs.
I have good snappy spark with both the battery test and when I rope it over with plugs out and grounded.
I’ve gone through the gearcase/lower unit. Fabricated 3 (or was it 2?) seals from nitrile rubber.
Cleaned out all the exhaust passages.
I’ve installed four new piston rings.
And I’ve cleaned the carb and fuel tank. New fuel lines w/inline filter. Don’t poo-poo me for that. It’s not permanent. I just don’t have any screen suitable for in tank filter.
Now, my concerns.
There is a cork that the popper valve in the carb hits. I replaced that cork.
Could that valve not be opening enough? It opens about 1/8” or lil’ less.
Could a .030 gap in plugs vs .025 keep it from starting?
I’ve been using 8:1 fuel mix.
Too much oil?
Is it possible that the plugs are not sparking once installed?
It really seems like they aren’t.
I’m lost.
G

JMGP

[Buccaneer]

Compression? Crankshaft bushings tight?

Prepare to be boarded!

[labrador-guy]

Geer you are not getting much help. I guess ya need to get back to the basics. Spark, compression, fuel. Sounds like your spark is ready to go. Compression needs to be above 50lbs. Higher is better but the motor should run with 50lbs. Did you check the end gap when you put the new rings in the motor? Sometimes when using fuel line filters on gravity feed systems fuel comes too slow. I found that out on my generator the last time the power went out. I blew on the gas tank when the motor started to die, the engine came right back to life. Took the filter off and she ran like a clock. Some people will blame no start problems on crankshaft seals or worn crankshaft bushings. Myself I have seen twocycles run with the crankshaft seals blown right out and dangling on the shaft. Motor did not run good but it ran. Idled about two thousand RPMs but it ran. Give it a break, take some time to think about it. You will have it going soon!

dale

[jcrigan]

The #386 spark plugs may be the resistor type. They may not work as well under compression.

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