What would cause new trigger to fail after 20 hours?

N

Nautique93

Seaman Apprentice
Joined
Nov 10, 2008
Messages
40
1983 Mercury 70. SN 9353189

I replaced trigger and stator last summer because they were both out of spec. This cured the problem of not revving past 4000 rpm. Now with less than 20 hours on the engine, the symptoms have returned, and the new trigger is now showing out of spec. What could cause this?

Readings are: Brown-white/black 824 (spec is 700-1000 so this is ok)
white-violet 1645 (spec is 700-1000)

The trigger i replaced last time was reading even higher:
Brown-white/black 1229
white-violet 2498

These readings are all taken at room temperature, and increase when engine is at operating temp.

Thanks, Peter
 
ajgraz

ajgraz

Lieutenant Commander
Joined
Mar 1, 2010
Messages
1,858
Re: What would cause new trigger to fail after 20 hours?

Did you replace with OEM parts? How old were they?

I recently bought a new old stock trigger for my 79 70hp, never been out of the box, yet the insulation on the wires was crumbled and the wires corroded because Mercury used some kind of crappy insulation compound back then.
 
N

Nautique93

Seaman Apprentice
Joined
Nov 10, 2008
Messages
40
Re: What would cause new trigger to fail after 20 hours?

Both brand new parts from the iboats store. Not sure if they are poor quality or if something is causing the failier. Im guessing the latter.
 
j_martin

j_martin

Admiral
Joined
Sep 22, 2006
Messages
7,474
Re: What would cause new trigger to fail after 20 hours?

The trigger moves physically for timing. The wiring harness from it has to be installed to allow for that movement without binding or pulling. Nailing it down real neat could kill it.
 
N

Nautique93

Seaman Apprentice
Joined
Nov 10, 2008
Messages
40
Re: What would cause new trigger to fail after 20 hours?

Plenty of slack for wires to move- i can manually move the trigger about and see that they are not binding. The only ignition items ive not replaced are the switchbox and the coils. Could either damage the trigger if faulty? Looks like im going to have to buy another trigger and i think i will get a switchbox as well.
 
C

CharlieB

Vice Admiral
Joined
Apr 10, 2007
Messages
5,617
Re: What would cause new trigger to fail after 20 hours?

Coils would have no effect on the trigger but a switchbox starting to go bad CAN prematurely kill triggers and/or a stator.

I very HIGHLY recommend CDIElectronics.com

Their ignition parts are unquestionably the BEST.
 
N

Nautique93

Seaman Apprentice
Joined
Nov 10, 2008
Messages
40
Re: What would cause new trigger to fail after 20 hours?

Interesting, thanks. I have ordered another trigger and a switchbox this time, so hopefully i get a bit more life out of this one! Just hope the switchbox hasn't damaged the stator as well. ohm readings are spot on, but i dont have a DVA meter to test accurately.
 
You must log in or register to reply here.
Top