1978 85hp loss of power then came back??

[1973searay]

Wondering if anyone had any ideas of where I should start...I have a 1978 Johnson Javelin 85hp. was out yesterday, motor starts up fine and idles great. Finally made it to where I could open it up and It planed out fine crusing for about 2 minutes when I lost I would say about half power and couldn't even plane out. Putted around the lake awhile then later on in the day it ran like a champ with full power no problem. Wondering if maybe something floating around in the carbs and was maybe clogging a jet and later on it cleared up? Posible for a coil to shut down and work again? I'm thinking either carbs need cleaned or maybe i'm losing a cylinder or two? Motor doesn't run rough or anything while doing this and it does idle fine just not hitting top rpms. I noticed at one point it was skipping in and out like it wanted to go full open but didn't until later in the day. So when I put it on the trailer it was running awsome so now i'm unsure where to start. Thanks for any input

 

[Daviet]

Re: 1978 85hp loss of power then came back??

That's a problem that you are going to have to check out while it is happening.
Try pumping the primer bulb, you might have a fuel pump acting up.
You can use a timing light to see if all the cylinders are firing.
Those kinds of problems can be a real challenge to figure out, I am sure someone else will come along and offer more suggestions.