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Merc 45 classic 50 possible switchbox problems

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kwhite771

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"I've got a 45hp elecctric

"I've got a 45hp elecctric start and am having problems that i have been told are due to a bad switchbox. could someone give me some input.
fuel flow is good, carbs are good, coils plugs and wires are good. when I am running at low rpm's things seem fine but when i put the gas to it it starts missing and losing power."
 
"Kevin, that doesn't sound

"Kevin, that doesn't sound like a switchbox.

It sounds more like a bad stator. Many Merc stators have both high and low speed windings.

The two separate windings produce A/C voltage which is sent to the switchbox.

The switchbox is simply a combination, rectifier that converts the AC to DC and then stores it in a capacitor until the trigger tells it to release the power to the appropriate coil.

The low speed windings produce power throughout the entire rpm band, starting at about 200 volts or so at idle and upwards of 300 volts above 4000 rpm. That provides enough power to fire both coils at the lower rpms and augments the high speed coils at higher rpms.

The high speed windings do essentially the same job, however, at idle they are only producing about 50 volts. Then as rpms increase, so does it's voltage, upwards of 300 volts (again above 4000 rpms).

It's at the higher rpms that ignition requires the 300 or so volts from BOTH of the windings.

Since your problem is occuring at higher rpms, I would first trouble shoot the stator since what you describe could be the exact result of the low speed side working correctly, but the high speed side producing no (or incorrect) voltage."
 
here is what i came up with.

here is what i came up with.
stator check.
bl to bl/wh 5.9k
red to red/wh 150ohms
bl to gnd no cont
rd to gnd no cont.
the manual i have says the bl to b/w should be 5.7k to 8.0k
and r to r/w should be 56-76 ohms.
does this look like a high speed stator prob to you.
 
Thanks jb. All wires were disc

Thanks jb. All wires were disconnected. oat was about 75 deg. F. I am going to check out that site now. unfortunantly my multimeter is at work.
let me know if you guys have any more input.
thanks again Kevin.
 
"can some one help** i

"can some one help** i have a 1982 115hp in line mercury can,t fine thermostat book talk about one but doesn,t show location thanks harold**"
 
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