coil test results... is it bad?

[andyhoss]

Re: coil test results... is it bad?

does anyone know a good procedure for testing a switchbox?? I found one on ebay for 270 bucks so I need to find out if its good before I buy one

 

[Motor Boater Bill]

Re: coil test results... is it bad?

Why buy a swichbox for 270 on eBay (unknown quantity) when you can get an aftermarket kit with the switchbox and coil for $240 from Grubbs?

 

[andyhoss]

Re: coil test results... is it bad?

switch box for 1971 mercury 650 is P/N 332-2986A27 and Grubbs has it listed for $356... the one on ebay appears to be same aftermarkey part and new... tell me if I'm overlooking something here- http://www.oldmercs.com/ignsys.html#332-2986A27 <br /><br />be sure to scroll down to the 4 clynder area<br /><br />does anyone know how to test theses guys my shop book only has testing procedures for other models...<br /><br />I recieved a used coil off of ebay today and still no spark all though I can not confirm if either is good...<br /><br />I gotta believe its the switch box at this point but would really like to confirm it

 

[molsenice]

Re: coil test results... is it bad?

As mine turned out, it was the switch box. I got the aftermarket switchbox / coil conversion and it was a sinch to hook up. Hints - if they say soider the conections, soider them. also, the brown wire on the four post side is for a tach, the aftermarket does not allow for a tach and therefor the brown gets taped off. the folks at Grubbs a ACE's and will call you back to explain any questions if they do not have an imediate answer (they called me about the brown wire). Good luck and let us know

 

[molsenice]

Re: coil test results... is it bad?

the fact that you say "It just stopped running" still makes me think. Did it quit like you ran out of gas? was it sputtering? It could also be in the trigger or a loose wire. Heck it could even be in the distributer itself. I was lucky (stupid but lucky) I knew what I did wrong. Just recieved the service manuel (would suggest you get one - very cheap $50) and it covers your motor year, will look it over and let you know if there is anything that might shed light on your situation.

 

[andyhoss]

Re: coil test results... is it bad?

when i went out the last time it became increasingly harder to start after everytime i turned the engine off until it wouldn't start at all... at that point i checked the spark in the spark plugs and found none i than traced the lack of spark back to the coil and confirmed there was power going into the switchbox I already own the shop manual

 

[andyhoss]

Re: coil test results... is it bad?

im not just guessing that it is the switchbox... i have power going into it and no spark coming out of the coil... that would seem to narrow it down... but im not just gonna throw 270 bucks on a part if i don't know if i need it.... my shop manual does not cover any switchbox testing procedures for my specific engine... does anyone know a good testing procedure for my switchbox??????

 

[Motor Boater Bill]

Re: coil test results... is it bad?

Check out this item at Grubbs, on the same page, right below your swirchbox:<br />332-2986K<br />Aftermarket switchbox and coil kit replaces 332-2986A21 or 332-2986A27 switchboxes (above).  Does not include sender for original style tachometers.<br />$240<br /><br />Sorry I can't help with testing the switchbox. Posts I have seen say you need a DVA meter to do it.

 

[molsenice]

Re: coil test results... is it bad?

refer to "Topic: Merc 80hp "800" ???Spark" guys there seam to have the method for testing the switchbox. Also it will let you know if it is the box or the trigger.

 

[andyhoss]

Re: coil test results... is it bad?

thank you bill and molsenice.... very helpful infomation.... I'll be working on this into the weekend and will let you know if I get to go boating on the 4th<br /><br />thanks again

 

[andyhoss21]

Re: coil test results... is it bad?

I'm a little confused about the ignition trigger, where exactly is it??<br /><br />I read on a thread titled switchbox testing - "You do not test switch boxes off the motor...you check all else in system and declare switch box bad by default....if you have power and control going into the box [stator an trigger] and nothing comin out, guess what? time for a box...... "<br /><br />I have 12 volts going into the read lead on switchbox, also there is 12 on white that drops to about 9 when turned over which I'm assuming is pretty normal... <br /><br />Would you say that the ignion trigger is fine than?

 

[Ben Konopacky]

Re: coil test results... is it bad?

that 9 vdc when eng. is turning over is low.i don't want to throw anymore sxit at you but here is a good test that elimonates low volts to the switch box when cranking. found this out by dumb luck after installing a New Batt.* disconnect the red and white off the switch box and isolate them,jumper the red and white terminals,use a spare batt.connect the pos.of the batt. to the jumpered terminals and the neg. batt.terminal to a good eng.ground. use the key to start (turn over) the eng. this will not lower the dcv to the switch box,if it fires and runs you have a low voltage problem with the other batt.CAUTION CAUTION the only way to shut down the eng. is to disconnect the neg.lead from the spare batt. Trigger is in the distributer,hope you are reading your Manual it should show all these components.<br />GOOD LUCK ANDY

 

[molsenice]

Re: coil test results... is it bad?

Figured a post to get your topic back to the front would be easier than looking around. Going away for a week, let us know how you make out - good luck