1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

TheChad

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Hey All,<br /><br />My 1979 Mercury 40HP's wire's are all getting old, and starting to fall apart.<br /><br />I pulled off the Ignition Switch box hoping that I would be able to get to the wires inside threw the bottom, but it looks like the bottom of the Ignition Switch box is siliconed in...<br /><br />Is there a way to replace the wires? or would i need to replace the entire Ignition switch box?<br /><br />Thanks.<br /><br />-TheChad
 

Laddies

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Chad it's about impossible to make a permant repair to those wires, for some reason most will not solder well and crimpons are temperarey at best
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

I was looking for a Replacement, its model 332- 4911. I found several places offering a Non-OEM replacement..<br /><br />Are thease reliable? Or should i stick with the OEM?<br /><br />Thanks<br /><br />-TheChad
 

Bob H.

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

If it's just the insulation that's bad you can cut off the terminal and use slide on some heat shrink tubing. You can solder on new sections but you'll need a good soldering iron, not the pencil type. I used a solder station and 750deg tip to redo mine.
 

Laddies

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Chad Rapair/CDI are better than original
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Originally posted by Baitis:<br /> If it's just the insulation that's bad you can cut off the terminal and use slide on some heat shrink tubing. You can solder on new sections but you'll need a good soldering iron, not the pencil type. I used a solder station and 750deg tip to redo mine.
That's actually a great Idea, I didn't even think about that!<br /><br />I have a really good Hakko Soldering station.<br /><br /><br />Which is better to do, Leave the origional wire, and use heat shrink to replace the crusty insulation, or cut the wire off near where it enters the Ignition Switch Box, and solder on new wire?<br /><br />Thanks for the help.<br /><br />-TheChad
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Originally posted by Laddies:<br /> Chad Rapair/CDI are better than original
Are you saying repairing the wires on mine is better than replacing it with a new unit, or are you saying the Aftermarket CDI's are better than the OEM CDI's??<br /><br />Thanks,<br /><br />-TheChad
 

Laddies

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

No replace it with CDI or Rapair products
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Originally posted by Laddies:<br /> No replace it with CDI or Rapair products
Oh, Repair CDI is a brand... Do you know their websight?<br /><br />The 2 Non-OEM brands I was seeing were Sierra & CDI..<br /><br />The CDI brand is about $125-$170 and says "Requires wire Splicing", the Sierra brand is about $150-$175 and is a "Direct Replacement" No splicing.<br /><br />The Sierra brand, looked like the OEM Switch box, the CDI brand looks nothing like the OEM switch box.<br /><br />Are the non-OEM just made better, or is there something performance wise that is better?<br /><br />P.S. Could the switch box be causing me not to get spark? Is there any way to test the switch box for functionality?<br /><br />Thanks again,<br /><br />-TheChad
 

phatmanmike

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

P.S. Could the switch box be causing me not to get spark?
absolutely. without it, spark does not exist
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Originally posted by myoutboards:<br />
P.S. Could the switch box be causing me not to get spark?
absolutely. without it, spark does not exist
Is there a way to test the switch box to verify that it is, or is not functioning correctly?<br /><br />Thanks<br /><br />-TheChad
 

Laddies

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Chad the stator and trigger can be tested with a OHM meter but a DVA is much better, do you have either available to you--Bob
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Originally posted by Laddies:<br /> Chad the stator and trigger can be tested with a OHM meter but a DVA is much better, do you have either available to you--Bob
I have Multi-Meter, that has an OHM Meter...<br /><br />What is a DVA?<br /><br />So how do i test the stator and trigger?<br /><br />(I assume testing the stator and trigger, will show if the Switch Box is bad?)<br /><br />Thanks,<br /><br />-TheChad
 

Laddies

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Chad, most people don't have a DVA (direct voltage adapter) when used with a voltmeter it reads peak voltage, so lets go with ohms first disconnect the blk/yellow wire from the box its the kill wire and test for spark no spark the kill circurt is not shorted<br /><br />Next ck the stator,<br />bll/yellow to grd = 3250-3650 ohms<br />blk/white to grd = 200-250 ohms<br />Next ck the trigger,<br />brn/yellow to brn/white = 750-1400 ohms<br />brn/yellow to grd = open<br />brn/white to grd = open<br />if these tests are OK then the switch box is no good<br />this test is for no spark on either cyl it takes a DVA to ck spark on only one cyl---Bob
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Originally posted by Laddies:<br /> Chad, most people don't have a DVA (direct voltage adapter) when used with a voltmeter it reads peak voltage, so lets go with ohms first disconnect the blk/yellow wire from the box its the kill wire and test for spark no spark the kill circurt is not shorted<br /><br />Next ck the stator,<br />bll/yellow to grd = 3250-3650 ohms<br />blk/white to grd = 200-250 ohms<br />Next ck the trigger,<br />brn/yellow to brn/white = 750-1400 ohms<br />brn/yellow to grd = open<br />brn/white to grd = open<br />if these tests are OK then the switch box is no good<br />this test is for no spark on either cyl it takes a DVA to ck spark on only one cyl---Bob
Thanks for the help Laddies,<br /><br />I could not find those exact color wires.. I've taken a picture of the wires to show you what I am working with, Maybe that will help...<br /><br /> Click Here For The Pictures<br /><br />Thanks again,<br /><br />-TheChad
 

Laddies

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

OK lets try again,test is the same pre 1978 colors are<br />orange is the kill wire it unhook and ck for spark<br />red is HS winding to grd = 200-250 ohm<br />blue is LS winding to grd = 3250-3650 ohm<br />white to brn =750-1400<br />brn to grd = open<br />white to grd = open
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Originally posted by Laddies:<br /> OK lets try again,test is the same pre 1978 colors are<br />orange is the kill wire it unhook and ck for spark<br />red is HS winding to grd = 200-250 ohm<br />blue is LS winding to grd = 3250-3650 ohm<br />white to brn =750-1400<br />brn to grd = open<br />white to grd = open
Awesome, Thanks. I will try thease tonight when i get home.<br /><br />The Engine is a 1979, its stamped on the info plate on the engine... But it was built in 1978.. (Weird that the wireing is Pre-1978...)<br /><br />I assume "Open" means no ohm reading? Should i be doing thease test with the key in the "On" Position?<br /><br />Thanks Again,<br /><br />-TheChad
 

Laddies

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

It could be a early production engine or someone may have changed the system for some reason
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Originally posted by Laddies:<br /> OK lets try again,test is the same pre 1978 colors are<br />orange is the kill wire it unhook and ck for spark<br />red is HS winding to grd = 200-250 ohm<br />blue is LS winding to grd = 3250-3650 ohm<br />white to brn =750-1400<br />brn to grd = open<br />white to grd = open
With Orange Wire disconnected, I turned over the engine, and got spark.<br /><br />Red -> Ground @ 2000 Ohms = 54<br />Blue -> Ground @ 20,000 Ohms = 3.83<br />White -> Brown @ 2000 Ohms = 697<br />Brown -> Ground = No Ohm Reading<br />White -> Ground = No Ohm Reading<br /><br />My Multi-Meter has a 3.5 Digit LCD Read Out. (If that helps to understand the readings I got!?)<br /><br />All readings were takin with the key in the "ON" Position.<br /><br />I don't know what all that means? But I am assuming that by disconnecting the Orange wire and getting spark, that is showing that the Switch Box is defective?<br /><br />Thanks again for all the help,<br /><br />-TheChad
 

TheChad

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Re: 1979 Mercury 40HP - Ignition Switch Box, Replacing wires...

Well, I ended up ordering the Sierra Brand Switch box, because its a direct replacement, no wire splicing required..<br /><br />It is schedualed to arrive today, I will post the outcome.<br /><br />Thanks,<br /><br />-TheChad
 
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