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89100hp Merc no spark

C

Collin Flick

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have 1989 sea-ray w/ 100h.p.M

have 1989 sea-ray w/ 100h.p.Merc.4cyl.{motor 89 also} Has no spark. What should my readings be at switch box from stator and trigger? What should meter be set on? Do I need to unhook rectefier before checking?
SOMEONE PLEASE HELP..
 
" Collin,

If you are using


" Collin,

If you are using an ordinary voltmeter, you won't get true readings. You need a peak reading voltmeter to get accurate readings. You can set a typical multimeter on milliamperes to test the trigger. If you get any reading at all it is probably working.

Check the stator voltage at the blue, red and white terminals on the switchbox. Touch the red lead to each terminal separately with the black lead connected to ground. Set the meter on A/C volts. You don't have to disconnect the voltage regulator for these tests.

Post the readings that you get here, and I'll tell you what I think.

Tony "
 
" Tony,
Here are the reading


" Tony,
Here are the readings I got. Red 5, blue 30, blue w/white stripe 4, red w/ white stripe 4. They are listed in order from top to bottom. I cranked the motor by key. With key on and jumping the starter solenoid, the readings came out different: red 7, blue up to 70, blue w/white 7, red w/ white 6. Not positive on meter type [peak reading.] Will find out for sure on Monday.
Thanks,
Collin "
 
" Collin,

It sounds like yo


" Collin,

It sounds like you are using an ordinary multimeter. Those readings sound normal to me.

You should check the grounding circuit, which turns the engine off. You will find a black-yellow, or an orange wire at the switchbox. Disconnect this wire and check for spark. If you get spark, there is a problem with the ignition switch, the mercury switch, or the wire itself.

The terminals on the left side of the switchbox are from the trigger to the switchbox, and from the switchbox to the coils. Check the wires from the trigger on the milliamperes scale and see if you get any reading.

Tony "
 
" Tony,

I checked trigger,


" Tony,

I checked trigger, all wires were o.k.

I unhooked black/yellow wire, still no spark.

Switch box is mounted upside down on my motor because of offset bolt holes. 5 leads on left,
8 on right side. Merc. sticker is upside down too.

Will look into meter type.

Thanks
Collin "
 
" Tony,
I was using wrong me


" Tony,
I was using wrong meter. I rechecked stator today . New readings are Red-8,Blue-72.8,Blue/white-5.6,Red/white-5.6 .
If you still think its the switchbox can you recommend where to order one, dealer wants $ 255.00 for one.

Thanks for your help
Collin "
 
" Collin,

You can get a sw


" Collin,

You can get a switchbox from an after market supplier, such as Sierra, for quite a bit less than that. Most marine stores would carry these products. You can find them for even less (rebuilt) at www.seilermarine.com, and other online distributors. Most of these are from Rapair (www.rapair.com ), a company that specializes in rebuilt electronic devices.

I should tell you that most manufacturers (including Mercury) warn that it is best to replace everything at once, because damaged components can cause other components to fail.

For instance, a shorted or discontinous igniton coil, can cause the switchbox to fail. Likewise, a bad switchbox, can damage the stator.

You might try checking the voltage at the black-yellow terminal on the switchbox before replacing the switchbox. Also, check the ground on the switchbox, and igniton coils.

Tony "
 
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