spark plug wire routing

[Senecadaze]

bought a used 50hp force not sure if the guy had wires on wrong plugs.
he said it backfires.
i removed flywheel and the key was sheered.
$25 bucks for a new one holy craps.
my question for you is does top coil go to top plug?and bottom to bottom plug?

 

[GA_Boater]

Welcome aboard.

No idea on the key. Some motors use special keys and some use off the shelf keys.

Don't know which coil connects to which plug, but logic says top to top and bottom to bottom.

I do see what could be some problems looking at the photo.

Clear the plug wires from the terminal strip to eliminate the chance of arcing. They appear to be pinched and that's not good.

Are the coils good? Is that gobs of silicone? Not a good sign sign.​

 

[Senecadaze]

the key is an odd one it fits in crank like normal key but extends down into lobed collar.
wires not pinched they route behind the wire strip.
silicone at first got my attention also, not sure why is there.
thanks for response.
i have not found in all my searching any info on fire order or routing wires maybe someone else will chime in.

 

[Nordin]

Routing the plug wires between the terminal strip and block is from factory.
The top coil is for top cylinder BUT someone could have changed it.
It is easy to check.
White wire at coil prime side is top cylinder.
You can double check by this.
Pull the plugs and ground them, check with a screwdriver when top cylinder is traveling up when turning the flywheel.
Set keyswitch in ignition position or connect a battery to terminal strip. Plus (+) at blue wire and minus (-) to ground black wire.
When turning the flywheel the plugs should spark just before (depending on throttle position) TDC at each cylinder.
Then check which coil is for which cylinder.

Shared key is not uncommon on these engines,when changing key you have to lap the crank taper and most importent is to torque the flywheel nut to proper value 80 ftlb..

 

[Senecadaze]

thank you Nordin!
also i have read of lapping the crank taper
could you explain that for me.
great help!
Great forum!

 

[Nordin]

Lapping is to make the surface at the crank taper clean and smooth.
You use grinding compound such as Carbo Rundum which is used when grinding valves in a 4 stroker.

Pull the flywheel and remove the flywheel key. Put a light coat of Carbo Rundum at the crank taper surface.
Put the flywheel on the taper and with a light force at the flywheel down wards turn the flywheel about 90 dgr back and forth.
Move the flywheel by lifting it off the taper and but it back about 90dgr from last position.
Turn the flywheel again with a light force down wards about 90 dgr back and forth.
Repeat this a couple of times then check the taper surface.
It should be smooth with a light grey colour.
Clean the taper and the flywheel surface well soo all compound been removed.

 

[jerryjerry05]

Since the motor backfired: it's possible the backfire affected the port cover gaskets??????
Starting fluid, start motor, spray the sf around the intake side of the motor.
Not into the carb but around the base and under the ignition components.

I'm sure you've checked the price of the coils?? $$$$$ $179 each.
From the looks of the sillycone it looks like they tried to help them along.

IF??? they still work, you can use the stuff you see on TV, the guy seals a screen door with it.
Paint the coils after filling the cracks with sillycone.
You can use this stuff on plug wires too. Cover with shrink wrap and then paint.
Replace the ends if they look suspect?

 

[Nordin]

About the cracks in the coils check out jerryjerrys suggest.
The cracks can be from the years (they can be from mid 60es) and another common parameter is if you leave the keyswitch in ON position when not running.
Current is still flowing in the prime side winding if the points is closed. It heats up the coil and the insulation will dry out and crack.
Remember, the points is closed most of the time during one turn of the flywheel.

Soo with a battery ignition system DO NOT LEAVE THE KEYSWICH IN ON POSITION when not running.

 

[Senecadaze]

thanks everyone of you for the great advice.
will be a few more days before my key gets here.
excited to see if shes a runner.
I will update my post as soon as i can.
thanks again.

 

[Senecadaze]

Great spark now.
Runs great as long as i hold my hand over the carb.
model 507F6A
1986
Any advice on carb work appreciated
thanks

 

[Nordin]

Clean the carb well, check and adjust the float.
Should be parallell with the egde where the bowl seal to the carb body.

Set the air/fuel mixture screw at 1 1/8 turn out of seated, then it should run decent.
Maybe you have to fine tune the air/fuel mixture.

 

[jerryjerry05]

Sounds like the jets need to be cleaned.

 

[Senecadaze]

wow easiest carb i ever worked on.
simple clean job reassembled and we have a runner.
ordered a new needle before cleaning should be here in a couple days.

 

[jerryjerry05]

SHHH you'll make everyone think they can fix their own!!

 

[Senecadaze]

jerryjerry you can fix your own!
with help from folks like you and nordin.
very thankfull for you all and this forum.

 

[wickware]

I agree that JerryJerry, Nordin, The Forum and Many Other have made this a "Great Forum" By Sharing! A Big Thanks To All!