90HP Johnson Running Rough *Pics & Video*

[ezmobee]

Re: 90HP Johnson Running Rough *Pics & Video*

Yes they do. Good job troubleshooting.

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

From what I can tell with it on the muffs, it revs a lot higher now..I won't be able to tell until Friday when I take it on the lake. Definitely needs coils tho. they are all cracked and melted a bit. Thanks for all the hhelp guys!

 

[ezmobee]

Re: 90HP Johnson Running Rough *Pics & Video*

...........

Mature.

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

UPDATE**

Okay i took it out on the water last night and it still is not running good! Idles fine, but its like even with the throttle pinned it only revs about half throttle making it never plane. It revs to the sky when its on the muffs, but not in the water..any other ideas? What else can i do to troubleshoot. Thanks!

 

[etracer68]

Re: 90HP Johnson Running Rough *Pics & Video*

Old coils?, or new coils?

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

Old. After cleaning that one up i started getting spark from it. I mean if the spark is good, then the coil is working properly right? They all seem to get equal spark now...idk. It revs perfect when on the muffs.

 

[Sprky]

Re: 90HP Johnson Running Rough *Pics & Video*

Do what I suggested and let the motor talk to you.

 

[etracer68]

Re: 90HP Johnson Running Rough *Pics & Video*

Replace the coils. You yourself siad, they were "all cracked and melted a bit". You can NOT test a coil completely for shorting, when its not under a load.

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

I got a deal on 2 new coils on ebay..those suckers are expensive new! I wanna make sure thats the problem before i buy two more. I have a video of it in the water i will post later.

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

I just talked to a local boat repair guy and he told me my problem is because i was running 87 octane in it..could this be true?

 

[Sprky]

Re: 90HP Johnson Running Rough *Pics & Video*

I just talked to a local boat repair guy and he told me my problem is because i was running 87 octane in it..could this be true?

Did you ask him why 87 would cause your problem....................

Find another mechanic

 

[etracer68]

Re: 90HP Johnson Running Rough *Pics & Video*

I run 87 octane all the time. The service manual also says, 87 octane, and no more then 10% ethanol.

I hope you have good luck with the coils you purchased on EBay. Im not sure I would buy used coils, unless I knew for sure they came off a good running motor though. And then I would only pay 20% of new cost.

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

The coils are like new off a good running motor. I got both for 20 bucks. So no biggie. Why would it rev nicely when on the muffs, but not in the water? why would the coils cause that if they are the problem?

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

What about the thermostats? what do these do when they need replaced?

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

Anyone know??

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

Back to the top! wanna get this fixed before the season is over!

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

anyone??

 

[Stryker23]

Re: 90HP Johnson Running Rough *Pics & Video*

okay, so i think im going to buy a carb kit, thermostat kit and 4 new coils. How hard are the carbs to
clean and rebuild the jets? ive worked on many 4 stroke carbs..

 

[yoster]

Re: 90HP Johnson Running Rough *Pics & Video*

While we recommend new coils, if they're giving out good spark and you still can't get up on plane, then your problem lies elsewhere. Again though, coils still recommended.. as the motor heats up, they can easily stop working.. causing a frustrating intermittent issue.

My vote is is needs a carb overhaul. Not difficult from what I understand.

 

[woodsyfeller]

Re: 90HP Johnson Running Rough *Pics & Video*

I could be way off base here but you said the exhaust sounds louder.Is it possible you have a crack in your lower end. Perhaps some fishing line caught in the prop causing some sort of drag?