How to test a coil in an antique outboard engine

[@kalleklp7291]

I just got two coils for my Johnson Seahorse 3 HP today. It's a 1964 but in mint condition, never repainted and the inside looks almost new. However, looking through the flywheel I immediately spotted the problem. The coils were rotten to the point the outer (Bakelite?) casing was cracked on both. I'll install new coils, clean up and adjust the breakers, and get this baby to run again. :) Thanks for this video. It confirmed what I was thinking about these coils.

[@rasalas2x]

Doug, I really enjoy your lectures on OB repair. You do a wonderful job explaining so that many more can learn and enjoy the art of the old outboards. Thanks and keep up the good work!! Rob

[@seanyboy150]

brilliant! i've spent the past 2 weeks scratching my head trying to figure out what was wrong with my mercury 7.5hp! after watching this video i borrowed and ohm meter and within 2 mins managed to determine that the secondary circuit on one coil was dead. cheers doug for the video! i nearly took it to a garage, at £40 an hour labour your video has just saved me a lot of money!

[@JoeBlowski]

You're wrong, because any ohmmeter will work, even the garden variety digital multi-meter that you can buy at Harbor Freight for a few dollars will work perfectly fine. What you thought was 6 ohms was actually 6,000 ohms which is good because secondary spec is between 3,000 and 10,000 ohms. The meter pegged because spec for the primary is between 1.5 to 3 ohms and you were using a high scale. Checking for continuity like this reveals very bad coils, but you can reveal slightly bad coils if you learn to use an ohmmeter correctly to accurately measure in order to confirm the resistance is within specs (acceptable range).

[@blink1821986]

This is a very detailed video I think I have this problem but I'm currently changing condensers then coils as 1 was damaged anyways only wish that you had done it on a digital metre so I kno what is good and what's bad and the setting to put it on

[@nickgrossmeyer5468]

Exalent explanation thank you

[@markwatson1970]

Hey Doug. Great information. I am looking for a coil for 1947 evinrude sportwin 3.3hp. It has two spark wires from the one coil assembly. Hard to find. Any help would be great.

[@chadshort2121]

Im looking for a 2 wire single coil for a 571-20 waterwitch. I believe its a 1937 2 cylinder with single coil and condenser with point. Do you happen to know what options i may have with other coils?

[@markeschmann5453]

Looking for 1935 evinrude outboard motor 1 1/4 horse coil

[@mrhamburger6936]

Could you use a digital ohm and volt meter to test or does it have to be an analog because I know that like on microwaves for the high voltage diode you have to use a analog meter with a title battery otherwise you can't get no reading on it

[@chadwassink7846]

Nice video. The coil from the J-25 looks just like the one from my A-70. It tests OK, but I think as it heats up I lose the secondary. The other coil was totally dead, and I rewound it. Are there any options for replacements on these? I have to imagine there are not many good originals out there on 80+ year old motors. I'll rewind this one also if needed but am hoping for an easier solution.

[@seanwileydoctorwiley6818]

I have a 1946 3.5 no spark how do I pull apart the get the to insides.. my friend was going to throw this motor away I want to bring it back to life

[@Wavezone304]

Pull off the fly wheel

[@cpgixxer]

@SnapDaddy5998 Use a flywheel puller with the appropriate grade 8 bolts.

[@josephmayotte8879]

Also called a Briggs and Stratton tickle. I've done it to buddies and my younger brother..

[@BSDenning0116]

I have a 1974 20hp Mercury and I want to test the coils. Will this procedure work for testing coils on non-magnito ignition systems?

[@givemaboot]

Great video! I need help! the rope broke in my '74 johnson, and I tried to fix it but it's above my pay grade! how do I rewind the spring and get it lined up?? Thanks!

[@80hdjenkins71]

its very simple,

[@thomasflynn642]

Hey, do you have a stator for mercury part number 336-399 A4 or 336-3996? where can i get a good used one?

[@Ronart1000]

is it ok if my reading on my secundairy circuit is 7Ohm instead of 6Ohm? im measuring exactly how it's told on the video. i hope someone can tell me! thx

[@frankdavidson9675]

this off the subject but it worth knowing ----if you have an old eng running hot that you can not find the problem no mater what you replace still runs hot remove thermastat cover spin eng listen for air hissing as piston goes up and down stop remove the head gasket look at the head gasket there will be a hole burned in the gasket replace head gasket to fix it this is eay to do first before removing lower unit to get to impeller its worth knowing this it cahappen on 40hp down

[@issacteamster]

i test out my coils the easy way my girlfriend holds the sparkplug wire in one hand the ground in the other i turn over the moter if she screams it works if she screams and swears at me it works really good-high voltage --no response coil is broken

[@OTtitan78]

If you have spark to your spark plug does that mean your ignition coil is good? any help is greatly appreciated thanks.

[@frankdavidson9675]

you faild to mention the condenser it is the most important part for max spark also all the points do is open the gd on the condenser lead to allow current to flow thru primary winding and condener which make the magnetic effect in secondary to send high voltage to spark plug this condenser has to match the primary coil in mfds i find more than likly the condenser is failing when no spark more so than he coil ther is no current flow thru the points if condenser is good if condenser is def or wrong value mfd the voltage can not get thru condenser so it jumps the open gap in the points to gd pitting the points eng will run like this but not good so make sure right condenser installed they are all values out there

[@shaneparker2631]

Do you have coils for a 1959 elgin 40? I cant find any anywhere.

[@frankdavidson9675]

try sears thats who had the elgin my first outboard was 5 hp elgin iwas about 12 had it in a barrel i was hooked on eng i am 88 still hooked on 53 didge m37 now LOL

[@frankdavidson9675]

looks like you are testing your fingers you can not let you finger touch metal part of test leads

[@frankdavidson9675]

another comment on outboards odd ball trbls. if you have an eng that will idle fine but will not rev up before take it the shop check this on your fuel hose connector there is a tiny oring each endof the hose thattiny orink over time can get a tore place that you can not see but it lets in air ---you know the eng sucks fuel from the tank while running but with this tore place it is sucking air so take a fish hook stick it in the oring jerk it out yoy buy these orings at ant boat shop keep a little pack in you tackle box now to in stall new oring put a little oil on it the press into hose fitting both ends fire it up. worth knowing.

[@nobodyspecialdotorgrichard5971]

Damn good video but, apperantly, i have a very unique coil. you went from examples of 1930 to 1970 Mine is a 1960 75hp starflite and I have No secondary! Only 2 wires and there is NO 3rd wire going to the spark plugs. Every single one you used as an example,had a secondary wire. There are literally only 2 wires on mine. No 3rd one! The more videos i watch the more confused I am. Not one shows the coil I have, which has only 2 wires. It DOES however, have a metal tab or button-looking thing sticking up out of the middle of the body of the coil, which I guess could be the contact for the "secondary". Is that my secondary??? I do not have an analog like the multimeter in this video. I have a digital. Which, by the way, has 5 different options: 200M, 200k, 20k, 2000 and 200..... I have no idea which setting to use! I'm lost.....

[@russg1801]

Your 1960 Starflite has BATTERY ignition, not magneto. There is ONE coil that fires into the center terminal of the distributor cap. IOW, you have a Kettering ignition, not a magneto system.

[@gpcdist]

Have a coil for 87 mercury 65 hp

[@russg1801]

It's NOT a 'stator plate' it's called an ARMATURE plate.

[@jajaid6]

hahahahaha!