79' Merc, 40hp, 2-cyl, Ignition Help Please

[kellyisu]

A few weeks ago, just got the boat on the water to troll for walleyes. She wouldn't stay idleing and would die (ran fine WOT), so I headed back in. To make long story short, as I was heading back in she suddenly killed within 3-4 seconds at almost full throttle. Wouldn't start-up afterwards. It's not a cooling problem I changed the impeller this year and is getting plenty of flow. Took the boat back to my buddies dad's place and did a spark check, nothing out of both. Compression checks good, not the plugs, or wires. Figured 1 of 3 thing- (1)switch box (2)stator (3)trigger. Went out on a limb and figured it was the #1-SB. Nope, didn't fire up today but havn't checked it for spark yet though. Battery did go dead after trying to start it for five minutes. My bad should have had it fully charged.

My big Question is for anyone who has experienced trigger or stator failure.
I did notice (after the boat failure) that when starting the motor, if leaving the ignition key turned for longer periods of time, a medium loud rattle noise at times up around the area of the stator and trigger. Any Ideas- it never did that before. It's nothing within the motor (pistons), all good there.
I think the problem lies between either or (stator or trigger), but was wondering if anyone has expeinced the same.

Thanks, Kelly
College student- trying to save some mula!
I love this website

 

[kellyisu]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

Ohhh, I wanted to state, I know about doing electrical readings to test if either are bad but my quetion is directed to the noise coming from around the stator-trigger area sometimes while trying to start the motor?
Thanks-Kelly

 

[Laddies]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

Kelly, we need the year or better the number off the switch box

 

[Laddies]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

My god I'm getting blinder in my old age you listed it a 79 here the test from CDI

 

[kellyisu]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

Thanks Laddies for the stator/trigger chart. I will test those today. Still curious about that extra rattle around the stator/trigger area when trying to start the motor after cranking it for several seconds(10-12sec.) Any ideas?
Thanks again!
Kelly

 

[kellyisu]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

Meant to say in my 1st post that I did replace the switch box and it didn't start up today when checking to see if that was the initial problem.

 

[Jimmy70]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

I wonder if somehow it threw a coil off the stator and that is what is making the noise. Just a thought, as the last stator I bought had a open stator as the orginal was encased in some rubberized goop.
Jimmy70

 

[kellyisu]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

I was going to test the stator and trigger wires (v meter read) with a buddy of mine who is an electrition but I want to test it by myself sooner than he can help me. I have shown how to do it above(helpful) and with an online manule(not very helpfull), but still kinda confused. Do I need to disconnect any wires?
Crank motor over to get reads?
Any help would be greatfull.
Thanks, Kelly

 

[Laddies]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

Kelly, for OHM tests you disconnect the wires for voltage tests you leave every thing hooked up

 

[kellyisu]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

TRIGGER:
-The trigger readings seamed ok;

STATOR:
-Didn't get any reading from the ohm test. Nothing from either the blue or red. (assuming I did it right, pretty sure I didn't screw that up)
-The volts reading seemed to jump all over the place ( ALL OVER)

Does that pretty much seal the deal for the stator?
Even though I got no Ohm reading, CAN OR WILL SOMETIMES A STATOR VOLT READING JUMP ALL OVER THE PLACE IF IT'S BAD?

Thanks everyone!

 

[Laddies]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

No ohm readings from the stator means that it has a open in it and if the voltage jumps around that sounds like it is arcing inside the stator

 

[kellyisu]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

Thanks for your help Laddies. I will replace the stator next week on my college budget and let you know how it all turns out.
Thanks again for the info: always a learning process- it can be a pain but I like building the knowledge.

 

[kellyisu]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

So, I finally got to changing my stator today after getting it in the mail. In my earlier postings I mentioned that after it broke down while trying to start it made a medium rattle under the flywheel sometimes. Well, I found out what the cause of that rattle was after taking off the flywheel. The 4 bolts holding the old stater in come all the way loose. When I pulled the flywheel off the stater come right out with it, SOB. When I saw that I just stared at it for a few seconds and said to myself, "I thought I was supposed to unscrew those bolts." Put the new one in tonight, used thread lock on them 4 bolts, and took her down to the river real quick. It's the best she has ran since I bought it 6 months ago. Before, I also had trouble starting it and keeping it running in idle or trolling speeds w/out giving it some throttle. Didn't have any of those problems tonight. Ran like a champ!!! Thanks
Kelly

 

[kellyisu]

Re: 79' Merc, 40hp, 2-cyl, If anyone is interested, results

Re: 79' Merc, 40hp, 2-cyl, If anyone is interested, results

Runs like a champ now

 

[MercFan]

Re: 79' Merc, 40hp, 2-cyl, If anyone is interested, results

Re: 79' Merc, 40hp, 2-cyl, If anyone is interested, results

Good stuff!
With a little luck the problems you had with keeping her going was just all the previous failed starts you had after she broke down. If she still battles to run at low speed, just post in this thread again.

 

[domains]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

stator are not tested like triggers ..on my ohm i think you set it a 20 for triggers and 200 for stators ...i know there not on same settings stators have more senative reading. just look for the right numbers stated and ajust ohm meter.

 

[domains]

Re: 79' Merc, 40hp, 2-cyl, Ignition Help Please

just looked old thread sorry new here