Need to pull carburetor 1988 9.9 Johnson

[bktheking]

Re: Need to pull carburetor 1988 9.9 Johnson

I imagine the nozzle is for the high speed feed of the carb but I might be wrong. The starer has to come apart- loosen the bolt and remove the starter. Carefully let the tension back itself off. Pull the plastic part with the teeth off, you will be left with the cup, spring and washer. Put grease on the washer to help it stay in place. Put the top tooth plastic piece back in where it alignes with the slot on the spring and put tension back on the way it came off and bolt it back up. Take note on the direction the spring tension is before you start. Do this slowly, you don't want that spring to come out, they are a PITA to recoil and may take out your eye if it jumps out uncontrolled.

 

[kgfishy1]

Re: Need to pull carburetor 1988 9.9 Johnson

Starter removed, washer replaced, working fine although that exercise is excruciating. I'm sure there are trucks that make the process easier and I wish I knew them. But, it's finally done.

With regard to the compression, this was a dream purchase wherein the guy and his dad used on the motor only for an Ontario fishing trip one week each year for seven years (until 1995) when his dad took ill and it sat for 15 years in a garage since. I'm estimating it to have only 30-35 hours on it. I test ran it on a 12' jon boat and it was flying that thing across the water. That said, any thoughts you have on compression testing would be welcomed. Many thanks.

 

[bktheking]

Re: Need to pull carburetor 1988 9.9 Johnson

Pull the plugs, test compression 5 or 6 rope pulls with tester screwed in tight , 100+ is good so long as they are both close to each other in PSI. There are no real tricks on those starters, I've pulled them off (recoil starters) 10+ times and reinstalled, it never gets easier.

 

[kgfishy1]

Re: Need to pull carburetor 1988 9.9 Johnson

bktheking...if you're still monitoring this thread, this motor now purrs like a kitten at idle (all day long) and runs like a cougar at mid to high range RPM. But, if I don't feather the choke during acceleration, it stalls. Installed a fuel pump kit but to no avail. What do you think is causing this?
Many thanks,
Kelley

 

[bonzoscott]

Re: Need to pull carburetor 1988 9.9 Johnson

I have cleaned my carb several times to achieve results. Probably because I didn't remove the welch plugs and I still can't picture that procedure. So I have had to remove the starter many times. It is difficult but Like BK said, it gets easier each time you do it. I think it's almost the same if you pull the spring out and reinstall. Use gloves and them construction clothes pin clamps while cup is bolted down.

 

[bktheking]

Re: Need to pull carburetor 1988 9.9 Johnson

Sounds like the carb isn't right still or it's sucking air from somewhere, carb-gasket-seals etc.

 

[kgfishy1]

Re: Need to pull carburetor 1988 9.9 Johnson

Yeah, that was my initial inclination so I pulled the carb and cleaned again (although it was spotless). Soaked it and used compressor to blow it out thoroughly. Seals look fine/like new. Where does that motor get it's increased fuel supply when accelerating from low rpm to mid-range rpm? That's the only range where there is a problem and manually closing the choke during acceleration until the motor reaches mid-range rpm avoids the issue.

 

[Bob_VT]

Re: Need to pull carburetor 1988 9.9 Johnson

Have you read through this link yet? http://www.sschapterpsa.com/ramblings/OMC/OMC info.htm

 

[kgfishy1]

Re: Need to pull carburetor 1988 9.9 Johnson

Thanks for the link. The only insights I get from that is the idle needle bushing shown on the pre-1987 models. I definitely don't have that part. However, my motor is actually a 1989, and the exploded view I have from shop2.evinrude.com
http://shop2.evinrude.com/Index.aspx?s1=qh49qbc6g1ul0pb91a5klv6fc7&catalog_id=0&siteid=1
doesn't show an idle needle bushing.
One other observation may help: the idle adjusting needle doesn't seem to have much impact, except when it's completely shut/tight. Otherwise, it doesn't seem to make any difference if it's backed off 3/4 turn, 1.5 turns, 4 turns, etc. Does this shed any light?
Many thanks.
PS If the cover sleeves were inserted improperly, would that cause this problem?

 

[dazk14]

Re: Need to pull carburetor 1988 9.9 Johnson

NOTE: THIS THREAD WAS POSTED BEFORE I SAW THE ABOVE THREAD...



I guess I'll pitch in here a bit...

1st - did you use a new carb kit, or simply cleaned the old ones.

The lower rubber gasket below the Nozzle Well(and above) has to be sealed/compressed. New kit no problems. No kit then you should flip the bottom gasket (under Well) since it will have taken a set and often not seal adequately.

The well is there to create a clean chamber of fuel, not pulling from the shmootz on the bottom and the idle circuit pulls from there as well (black 1/8"tube).

How many turns out are you for the idle mixture? These later plastic carbs start out at 2 1/2 turns out. If your too lean, it will hesitate/stumble off idle and even conk out although it may idle fine.

Is your link and sync set?

I would start by going richer on the idle mixture. The quick and dirty way is to warm it up, then keep backing mixture screw out counter-clockwise until the rpm's start to drop a bit. Then clockwise an 1/8" turn, then test its acceleration ability.
Tank testing is fine. If it solves it then, go back and find your perfect mixture setting and retest accel. The idle mixture is for idle and just off idle, so the latter must always be checked as part of carb tuning.

I'll post a little more on removing the rope starter to add to the options available for this job.

Step 1 pull a couple feet of rope out and secure a slip knot in front to prevent it from rewinding.



Although I don't use this method, a small c-clamp can be used to keep bottom and top of starter together (pictured). I prefer to use a 2" spring clamp, but I usually have to start loosening the main starter bolt, then it tips and can be spring clamped (pictured).




Once it's spring clamped and starter removed, you can add a measure of safety by threading on a 3/8"-16 nut onto the starter bolt(pictured). Leave the spring clamp on to prevent it from rewinding. NOTE: The pic above showing clamp and nut on bench is for illustration only -NO need to remove rope pull handle.

Do your work.

When reinstalling starter, loosen the slip knot in front of lower cowl, this gives you a lot of rope freedom when reinstalling the starter, so it's not pulling on you.
Of course remove the 3/8"-16 nut. but ensure the starter is clamped together with your favorite method , or both.
I tend to simply hand squeeze it together when re-installing, but I've done quite a few.
OMC does suggest loctite blue on the bolt threads, but few do it that way, although I do.
As the King mentioned earlier, rotating the flywheel so that the indent for the emergency rope start is over the starter bolt, gives a little more room.

Hope this helps.

When you find the solution please post back here for future 9.9ers.

 

[bktheking]

Re: Need to pull carburetor 1988 9.9 Johnson

Did you read the carb bit about warpage of the top cover?

"The original carburetors used on the 1988 -1992 9.9 HP had a plastic cover which didn't have a sufficient number or retaining screws that let the cover flex on acceleration and could cause hard starting, stalling or stumbling, erratic idle and leaking of gas. The new carburetor, part # 436779 is a factory update carburetor which replaced these defective top plastic bodied carburetors. Dealer cost was $244.42." It is not known whether this was a factory recall on this, but more than likely only if you brought it in to the dealer & complained during a specified time frame. Now that OMC has sold, it surely is not honored anymore even if available.

The above problem was found by a reader of this article, Greg DeWald of Mattawan, MI. who shared the following on his 15 hp 1989 motor & the solution he implemented to correct the problem: "The problem was attributed to the top plastic idle circuit cover warping because of inadequate clamp pressure from the screws and plastic flex / deformation, which allows air into the idle circuit. If you look at your picture you posted in your writings, you will see that there is no screw at the right inside corner of the top plate in proximity of the throttle cam roller. It is here that the plastic plate was warping upward, allowing air to enter, and when shut off, fuel to escape.

The photo on Leeroy's site shows the before and after with the additional screw.

 

[kgfishy1]

Re: Need to pull carburetor 1988 9.9 Johnson

Thanks for the thoughtful post, dazk14. But, if you read page 1 of this thread, been there-done that.
bktheking-- Yeah, I did see/read that. Don't think that's the case here as this motor only had about 30 hours on it when I got it. It looked new under the cowling. Zero dust.
NEW CONFUSING DATA. Worked on in yard Saturday to no avail. All the same symptoms: idles fine, dies upon acceleration unless the choke is feathered. Decided to go crabbing Sunday anyway because the condition was manageable. Ran like a champ all day, except upon startup and initial acceleration to plane. I dunno. We have a HUGE problem in the Northern Virginia area at the moment with stink bugs. They get into everything -- inside locked cars, inside storm windows, inside the cowling to this motor. I think maybe bugs are getting into the open mouthed air silencer and subsequently sucked into the carb and potentially clogging the jets. I have stuffed a folded piece of cloth into the mouth of the air silencer and plan on leaving it there except when the motor is in use. Does anyone know why the manufacturers don't put some sort of screen in these air silencers? It doesn't take much to clog a needle jet.

One other thought: when cleaning, the float was not 100% level with the bowl. It was going very slightly downhill from hinge. Didn't seem like worth adjusting. Do you think that could be playing a role?