Mercury ignition parts - uk

[thestig1973]

Helpful clip, thanks

[thestig1973]

Test #13 repeated



Hope this is correct setting (200k)

As 200 gets no reading

[thestig1973]

Test #14 repeated

[Fenlander]

OK... your meter ranges differently to mine and I've just noted the manual is confusing (whoops sorry first time I've expanded it on a large screen and I hadn't noticed you mention this in post #7 until just now) in that it refers on pages 2A-8 & 2A-9 to the readings on the scales of the Mercury own multimeter according to its ranges... not the actual spec readings. The actual readings are on page 2A-1.

For the stator high speed winding your figure of 132ohms is fine for the spec of 120-180.

For the low speed winding you have 2980ohms from a spec of 3200-3800
which is a little low but remember the specs are for 20degC so a bit low is OK.

For the diode test (your #13) you have 2900ohms from a spec of 3100-3700 which is only a little low and the cold applies again.

So to me the stator seems OK... do you agree?

On the trigger test (your #14) you have reading of 697ohms when the range should be between 6500-8500 by the book.

So unless you can see I'm looking at something incorrectly it seems the trigger is the one out of spec (assuming you did have the trigger unplugged from the CDI unit for testing).

Then add to this you commented a while ago it was only sparking on one cylinder and I think I replied that the stator feeds to the CDI box for both cylinders... so with the stator it is either both working or none working.

However the trigger is responsible for firing one or other cylinder so a trigger fault could in my mind be capable of just affecting one cylinder.

Unless you or anyone else can see a flaw in the logic I'd be wondering about trying another trigger... but don't hate me if it didn't work because even with the motor in front of you electronics can be a nightmare to resolve!!

Trigger that looks the right one here... Mariner mercury outboard Trigger Assembly 98450A 5 6 8 9.9 15 20 25 hp 2 stroke | eBay

I'd ask a seller to test the resistance and tell you before buying without giving him an idea what figure you're expecting. If his measured around 700ohms too then there's some real head scratching to do.

[thestig1973]

Hi, yes I agree stator seems fine, resistance is close enough to spec considering current temperature, and as you mentioned it must be working as one coil is sparking 👍


Trigger would explain firing on only one cylinder, also the engine died as though I'd pulled the kill cord....

The only other part that could cause this issue to my knowledge is the CDI which I understand rarely fail


I'm well aware that electrical problems can be difficult to diagnose, but I'm happy to buy a trigger and hope for the best, great advice regarding seller to do resistance test

I will speak to the guy selling the trigger tomorrow and let you know how I get on, thanks for your input David 😀

[thestig1973]

Trigger ordered

Fingers crossed 👍

[thestig1973]

Test #14 - new trigger

Same readings so presumably original trigger is ok

Really confused now.... Switch box issue possibly?

[Fenlander]

It is possible for a fault inside the switch box to damage the trigger coil. I assume you haven't tried this one on the outboard and the reading is as it arrived?

Assuming neither of us is making a daft mistake in seeing your test result as about 700ohms when the book says 6500-8500ohms then it's possible this trigger has the same fault as your own one.... or is there something wrong with the spec in the manual??

If you wanted I reckon you could return it as faulty by sending the guy a pic of the reading together with a link to the makers spec.

Had this trigger coil measured in the 6500-8500 range and you tried it and the problem still existed I think you would have proved it had to be the switch box. As this trigger reads the same as your old one (and we think that is a reading of 10% of that expected) sadly it's not really proved anything.

What about getting hold of Phantom 19 http://www.rib.net/forum/f10/mariner...etc-71793.html and see about buying all or part of his used (but from a running outboard) 9.9/15 electronics?? You could ask him to test the resistance of his trigger unit before buying. Perhaps you could buy the whole lot and sell off what you don't need once yours is running??

[thestig1973]

Some good

[thestig1973]

Some good ideas there David, I did contact phantom 19 yesterday, I will contact eBay seller today and possibly return trigger

[thestig1973]

And yes, trigger was tested as it arrived, not been connected to switch box

[thestig1973]

PROBLEM SOLVED 😀😀😀😀

New (used) switchbox arrived today, replaced old unit, first pull of the cord and it was running sweet

Thanks to everyone for your help, and David your input saved me a small fortune 👍

Now I can plan my next trip out

[Fenlander]

Good result... I only encouraged you to keep looking, testing and thinking!

Weather is great this way at the moment... might you get out soon?

[thestig1973]

Originally Posted by Fenlander

Good result... I only encouraged you to keep looking, testing and thinking!

Weather is great this way at the moment... might you get out soon?

Hopefully take a day off work next week if the weather stays decent

Looking back, even though the electrical problem has been a pain, it's taught me a little about 2 stroke electrics, and not been too harsh on the wallet so not all bad in the end