Carb rebuild Q: 84 johnson 90hp

[Thirsty Endgrain]

I know I have another thread going, apologies if I should post in that but it's getting cluttered with my other questions.

Just got the carb kits and I'm going through them (again-now actually having the kits). They came with o-rings at the drain screws, but the old ones leaked when I put it back together to prime the other day. There are new o-rings with the kit, but when I screw the drain screws back in I don't feel the o-rings making a seal. There are also fiber washers, and it looks like there is a machined surface for a washer, so now I'm confused. Should I use the o-ring, or does this get a fiber washer?

 

[racerone]

I believe those use the O-ring.

 

[Thirsty Endgrain]

Thank you. Doesn't seem to make a seal but I'll get it back together and prime it, and go from there...

 

[racerone]

What brand & part # were your carburetor kits.-----Factory or something else ?

 

[Thirsty Endgrain]

It was Sierra 18-7046. In their parts breakdown they show using a gasket and not an o-ring. Thinking I should have gotten a factory kit now. Their o-rings are smaller in diameter and thickness than the ones that came out (which leaked)...

 

[oldboat1]

Are you sure that's an '84 carb bowl? 2 jets, 2 screw plugs, O-rings.

 

[Thirsty Endgrain]

Well, it's what came on this engine when I bought it, that's the only thing I know for sure. Engine is a J90MLCRD.

 

[racerone]

From the little bit that I see it looks just like a factory 84 model float bowl.

 

[oldboat1]

On an enlarged view, the carb threads look like they might be buggered up a bit -- and maybe an old O-ring in there. In any case, you might take the screws into the local hardware and see what O-ring assortment they have. Additionally, some teflon tape around the screw might stop the leak.

 

[Thirsty Endgrain]

I left the old o-ring on in the pic to show the difference between what came out and what came with the kit. For now I've used the gaskets they detailed, and upon priming them full the gaskets aren't leaking. I think I will get some o-rings though down the road, it's weird that the supplied ones aren't big enough.

When I squeeze the primer bulb hard though the bottom carb will shoot fuel out of the two little brass ?outlets? (whatever those are, not familiar with all of the carb parts yet). Seems like this means the needle and seat or float has an issue. I installed everything what I thought was correctly - float is level, square etc. needle sits nicely in the seat, I can hear the float move when I tip the carb up or down, clean new fuel and lines, all purged out pre-assembly. Should the carbs under no circumstances push fuel out of those holes? I was squeezing hard to make sure it was primed, maybe too hard?

 

[racerone]

Why would you squeeze the bulb extra hard.------Makes no sense to me.----And there is no reason to do that.

 

[Thirsty Endgrain]

Because I'm new to outboards and I'm making mistakes and hoping that those smarter than me will ask me those kinds of questions to help me learn