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Have a parts problem (Help)

M

Mikey N.C.

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Customer brought in a , found out 1977 20hp mariner. Serial # 653 S 11669
I've got 135 v with dva on gray wire to #2 coil pull start!, orange wire #1 coil primary only 80-100 v , with pull. Gets spark to plug # 2, but not #1 plug wire.
I've reversed coils , still no spark at #1. If I'm wrong please tell me !!! I pulled flywheel and it has old , ignition coils or lighting coils. The grouped together coils under flywheel they're binded together are the 2 red wires for charge, which those wires go to no connection.. At the rear there is same type copper wound coils that are individuals, gray wire from 1 and orange wire from other, screwed together 1 on top of other. Question there's 2 sets of points, 1 for gray wire and other for orange wire. 1 set o points is burnt ( cylinder that's not firing) I called Mercury and have researched to no help at all. Mercury said they will call me back. They couldn't find part # for breaker points. Also I don't have tool to put on crankshaft to set points.
If anyone can shine a lite in the rite direction with breaker points # number and tool # number to set gap. Would be highly appreciated. THANKS
 
That is a Yamaha built 20 hp. Doesn't that have an access plate on the flywheel to get to the points. If that is the motor I am thinking of the points cam is on the flywheel. Those motors use lighting coils under the flywheel. A dealer will be your only choice because the Mercury parts fiche goes back to the mid 80s. DEalers can go back farther and should be able to find your parts but I bet they are NLA.
 
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Flyingscott, thanks you nailed it !! there are accessible holes in flywheel I didn't see because their is a gasket when you remove cover to get to flywheel nut. I hadn't looked. Until this morning and BOOM they were there as you said. I sanded them good, reinstalled flywheel and tried to set as book says. Woodruf key is good , I have dail indicator that screws in spark plug hole, book says tdc #1 zero dail then turn flywheel counterclockwise .092 +-.009, if I did that ( throttle WO) access hole to points for gray wire #1 points. Can't get feeler gauge to gap, I ground down feeler gauge.( book said .010-.018 for 2a,4a,8a and .012-.018 on all others)so I set at happy med. .015. Didn't get a chance to get on rewind start. We'll see in the morning.
Oh yea, Mercury called me back at 4:46 this afternoon we were shutting down shop. So his message to me was , he found someone with fishc cards and wanted pics.
 
I used to work on a lot of those and had stainless feeler gauges. Because they are such a pain to set when the feeler gauge keeps sticking to the magnet. If you still dont have spark it is probably the condensor.
 
10-4 thanks , yes mags. We're pulling straight screw driver to open and close points, had to have helper to tighten Phil head screw. SS feelers ��. Did u have to grind down to fit ?
And is that .092 rite, cause I couldn't see point, opening at that .092 backwards. So what I'd was watch and see when opening started and watched. At wide open , I was about .035 away.
But set them at the open point ?
 
I usually just set the gap when they open like any other set of points. I bought stainless shim stock to make my gauges Brass works to. That is about all I remember about those. I do remember that when you get it running right it is one of the nicest running 20s you will find.
 
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Mercury in fodo in WI. Cause I can't spell . finally text back and said thier , at a loss
Said 20 hp mariner was a Samsun built motor for yammy . And no g after sun. Merc. Said can't even find 653 motor. Can't send pic . won't load them
 
Thanks faztbullet, would someone please tell how with dva how to read lighting coil output with rewind starter ? Motor has individual stacked coils for ignition coils one with grey wire other with orange wire. The other lighting coil is grouped together, with 2 red wires. Motor doesn't have starter ( it did at one time) but no rectifier/ regulator, those ( red wires just hanging ) if someone could pm me a text number I can text pics. Of coils and points. I know I'm getting voltage to primary wires ( grey an orange) but can't really get a good output reading. I've pulled plugs and put impact air wrench on flywheel nut , but will not spin, I'm afraid of stripping flywheel nut, so didn't attempt anymore. Motor spins good with hand pull and I can get after 4-5 pulls about 120 psi on both cylinders..
As said mercury in fon do lac WI. Said they are at a loss. Then said motor was the Sam �� motor ? Any clue . I don't want to tell customer that it's a boat anchor. Thanks for advice.
 
Faztbullet are those charger coil NLA ? Or can I swap the 2 grouped together( if working ) and then later find if I'm 180° out? Or does charge coils not put out enough. ?
 
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