Dam it not again

[steplift20]

Ok this is my problem today, I went out with my 1978 Steplift she has a 1988 150 Mercury blackmax , she was running great then she lost power for a split second but kept going, then it happened again it felt like it was bogged down but only for a split second, we drifted awhile and when we started her she started and stalled when it went in gear, she did that a couple of times, then she would not start, we got her going but she felt like it was missing and only running on three plugs, it would be normal than bog down ,no power but we got back to the ramp , what do you guys think? And what should I check? I have a idea but want to hear what you think . Thanks for any feedback p.s. The fishing sucked in sandy hook today

[RWilson2526]

Damn, that is about the identical situation I had last week out at the Highlands. Maybe we can kill 2 birds with one stone. I've eliminated fuel issues at least up to the carbs.

[steplift20]

It's not a fuel issue definitely electrical , the way she was running definitely electrical. What motor do you have?

[phatdaddy]

Go to harbor freight and pick up a fire fly type spark plug tester, less than 5 bucks

https://www.harborfreight.com/90-in-line-spark-checker-63593.html

Run it on the hose to see if it’s firing on all cylinders

Is your tach acting wacky

[RWilson2526]

I should probably start a new thread so not to hijack this one. but yes as I was playing around with fuel lines and such the tach would read zero at times and work normally at others

[RWilson2526]

It's not a fuel issue definitely electrical , the way she was running definitely electrical. What motor do you have?

1986 Yamaha 150

[steplift20]

Tach was good, I had the stator replaced 2 years ago along with the trigger but I have had issues with my stators,
I must have had them replaced 5 times and one within a year. Can a switch box be tested?

[phatdaddy]

Only way i know is to swap it and if problem goes to other 3 plugs, its a bad box..

Also if you replace one, might as well do both

[steplift20]

Yes phat but does the stator fire three plugs on one side what I mean if I'm losing three plugs on one side I know it could be a switch box but can a stator do the same thing?

[phatdaddy]

I am not a mechanic, but the way i understand it, if your motor is charging, your stator is working.

The switch boxes are like a distributor on a car, sends the fire to the right plug at the right time.

Have u determined that it is only hitting on 3 cylinders?

[steplift20]

Thanks phat, one more question, I have seen switch boxes on Amazon,2 for 59,00 but they have a ground wire and I think mine are grounded to the block when you install them so I am Leary about getting them cause they have a ground wire and the Mercury ones do not have a ground wire ,it's grounded to the block when installed, what do you think?
The ones on Amazon are from CDI.

[phatdaddy]

That s more of a Spare or Ferm question. I would not buy used ones, no matter how cheap.

As far as the grounds, I think mine grounded through the mounting bolts

[steplift20]

Phatdaddy, they are brand new 2 for 59,00 from Amazon , they are not quick silver they are from CDI an off market brand but the only thing that I see is that they have a ground wire and the quick silver ,Mercury brand does not have a ground wire . The boxes ground by screwing them into the block. They say they are a replacement and the price is wwhey cheaper

[phatdaddy]

I used a CDI switchbox on a 40 hp i had worked great.

So have you definitely determined it is only running do 3 cyl
One box is for the port side and the other for starboard.

Sounds like you are still not sure what your issue is

[steplift20]

Mercury switch box 275.00 each CDI 59.00 for a pair Amazon

[THEFERMANATOR]

CDI makes most OEM replacement electrical parts on these old engines now. The part that concerns me is Amazon is running over with counterfeit parts. They label them as good ones, but you get knock offs when they show up. I only buy from reputable sellers for that very reason.

[steplift20]

Hey fermanator, I see you live in Florida,when you move to nj you are going to be my outboard mechanic. You will make a lot of money here. Not to many good outboard mechanics here.