Suzuki 5-hp 2-stroke; what does the "adjuster" adjust?

[onestepcsy37]

that was my thought too, that the beveled edge of the screw might be raising/lowering the nozzle. you could disassemble the carburetor to check on that.

well, think of this excercise as a way of keeping in touch with boating while you're hauled out for the winter.

i think i know where there is a suzuki engine manual from that era - a marine junk shop with a huge library of used books. but it's fifty miles from me so it may be awhile before i can get there. if i do i'll let you know what i find, or if it's only a few bucks i'll pick it up and send it to you.

[ranger58sb]

Originally Posted by onestepcsy37

that was my thought too, that the beveled edge of the screw might be raising/lowering the nozzle. you could disassemble the carburetor to check on that.

well, think of this excercise as a way of keeping in touch with boating while you're hauled out for the winter.

i think i know where there is a suzuki engine manual from that era - a marine junk shop with a huge library of used books. but it's fifty miles from me so it may be awhile before i can get there. if i do i'll let you know what i find, or if it's only a few bucks i'll pick it up and send it to you.

That's a wonderful offer, over and above, thanks very much! I don't actually feel comfortable asking someone to make any kind of special trip like that... but certainly if you happen to be going on your own accord and stumble across something like that, it'd be great!

"Ground truth" from Suzuki, maybe -- I don't often see the real McCoy when it comes to factory instructions about carburetors

As it happens... the motor has actually been running fine (once I sorted out some ethanol issues) so I think I probably don't want to dismantle the carb until I actually need to. OTOH, when we put it back in service, I can certainly fool around with this "adjuster" thingy to see what affect it might cause.

I just love puzzles...



-Chris

[motion30]

Or just maybe it is a drain screw.
.
I was a suzuki dealer for 8 years

[ranger58sb]

Originally Posted by motion30

Or just maybe it is a drain screw.
.
I was a suzuki dealer for 8 years

Yes, there was a comment above that maybe it's a drain... and one of my later links labels one of them a drain... but the other link, apparently to the same type of part in the same type of place calls it a pilot screw. (Given there are other "pilot" screws (both fuel and air), it's not clear to me what a third pilot thing would do?

And there's a drain bolt located at the very bottom/middle of the float chamber. Seems a screw on the side -- and higher than the bottom -- wouldn't be much of a drain ?

Do you remember if Suzuki carburetors routinely incorporated separate jets/air screws for both low speed AND idle (i.e., idle as differentiated from low speed)? Adjustments for idle speed would be a different from adjustments for low speed?

-Chris

[onestepcsy37]

in all of my limited carburetor work there have only been two screws - low speed and high speed, and in fact i think my old evinrude carb only had one (either low or high, can't remember that far back).

the last carb i worked on was this past summer on my yamaha 3, and it has low and high and nothing else.

[tropicalescape]

I have this type setup on a Kawisaki 440-B and it is a dual carb set up (as opposed to a single carb on a "regular 440-A")and the two carbs have this same type screw in the same place as yours and there is a piece of fuel line joining them together thru this "port",so I think it is used only on a duel carb setup(more HP) that being said I also have a single carb setup on another engine that has this same "port" and it has a piece of fuel tubing(nipple inserted where yours has a " jet set"screw)and the tubing goes up to the venturie at the air intake and feeds fuel into it.. I think this is some sort of over flow that will assist the carb when at an extreme angle..I have pulled this tubing off and pluged the hole and when the aircraft was put into a wing over it sputtered and spit,when I replaced it with the tubing it did not sputter and spit...good luck ,I dont think it much matters with your application

[ranger58sb]

Hmmm... pretty tiny carb, for an airplane

Had to look that up; approx. 51 hp or so? Must be pretty small tubing in that dual-carb applicattion? the adjuster screw isn't very "fat."

Anyway, I think if that "the tubing goes up to the venturie at the air intake and feeds fuel into it" then maybe this adjuster would be a fuel adjustment on my outboard.

Still guessing, of course...

-Chris

[tropicalescape]

Originally Posted by ranger42c

Hmmm... pretty tiny carb, for an airplane

Had to look that up; approx. 51 hp or so? Must be pretty small tubing in that dual-carb applicattion? the adjuster screw isn't very "fat."

Anyway, I think if that "the tubing goes up to the venturie at the air intake and feeds fuel into it" then maybe this adjuster would be a fuel adjustment on my outboard.

Still guessing, of course...

-Chris

The carb is same type (diaphram pump ), mine is a lot larger than the one on a 5 hp..My understanding is that,the tube feeds fuel back to the intake(air) and it is a "Fuel saving "and "pre-reed valve" type of set up..most I have seen have been bypassed and a screw put in place,like yours looks...could be something else ,hope you figure it out..

[Ericsstinnett]

Hate to dig up a old post but has anyone made any progress with this issue, I'm experiencing my Suzuki 4 HP not running at idle.

[ranger58sb]

I never did completely come to grips with it... but the engine began running better when I cleaned out the fuel system and lines from the most recent batch of ethanol-gas that I'd been running at the time. (You might just try that, see if it helps, if you've been running ethanol...)

And then I finally pulled the trigger on the larger, electric start, outboard I'd been conceptualizing for the previous 10 years or so... which became even more attractive once Suzuki introduced their lightweight (relatively) fuel-injected 9.9/15/20-hp models.

So I haven't tried to run the Johnson (Suzuki) for a couple years now...

-Chris