Defective Carb help

[mattsylvan]

i have an 1980 75hp johnson stinger and i took it in to a dealer to get it look at and they showed me a a srvice bulletin about the same year 70/75 hp motors that they had either one or all the carbs where defective. my question is has anyone have this happen to them and how did you fix the problem?

PS: problem my motor was doing had to choke motor get get full throttle, would bog down if didn't choke.

 

[Daviet]

Re: Defective Carb help

Don't know about defective carbs, I would think that with as many of those out there running, someone on here would know about it. But it does sound like it's time to rebuild your carbs.

 

[mattsylvan]

Re: Defective Carb help

they where rebuilt last year but could it be that they need to be rebuilt again? but i can still run the motor fine at idle and i can get up to 20mph slowly but thats if i choke it and wot i have to choke it or the motor dies out

 

[Lion hunter]

Re: Defective Carb help

If it was a service bulletin and not a recall i'ts likely there is a fix. Did you ask the dealer for a copy of the bulletin. They will usually explain the remedy.

 

[mattsylvan]

Re: Defective Carb help

they said that they dont make the carbs anymore but they want to put in a different orfice so it has a richer fuel mixture becuase he said when the motor bogs down there is not enough fuel getting to the motor for the high rpms. The bulletin said if the choking the motor to get high rpms works you could have one or more defective carbs and it said if choking he motor bogs it down i something with the feul sending device

 

[tashasdaddy]

Re: Defective Carb help

this is the first i have heard of this. my suggestion is to read ethanol. carb cleaning, timing, here>> http://forums.iboats.com/showthread.php?t=299680 and link n sinc in your service manual. it sounds to me that you have a fuel restriction, in the high speed jets. choking a motor usually bogs it down anyway, because you are flooding the motor with fuel, changing the fuel air mixture.

imho, he is blowing smoke up your skirt.

 

[F_R]

Re: Defective Carb help

this is the first i have heard of this. my suggestion is to read ethanol. carb cleaning, timing, here>> http://forums.iboats.com/showthread.php?t=299680 and link n sinc in your service manual. it sounds to me that you have a fuel restriction, in the high speed jets. choking a motor usually bogs it down anyway, because you are flooding the motor with fuel, changing the fuel air mixture.

imho, he is blowing smoke up your skirt.

I have no knowledge of the service bulliten, but that doesn't mean it doesn't exist. If the dealer showed it to you and it matches your model, then it might be significant.

Of course, running lean usually means too small an orifice, or an orifice that is dirty. That doesn't apply if the carburetor itself was defective from the factory.

And then again, maybe tash's smoke therory......

 

[mattsylvan]

Re: Defective Carb help

i believe that he is just taking me for money but the carbs looked clean, we ran premuim in it so there should not be any ethanol in the fuel, i believe though it could be timing because i had to put a new throttling cable on it, and still had the problem where i had to choke to motor to get it to full throttle. oh wait i remember something when i tested it last time with the premuim fuel and new cable i slowly got up to 20mph thats it and the motors top speed was 31mph. could it be fuel restriction and the possibly jets? for that fact that when i choked i, i slowly got to 20mph and that was it choking it didnt do anything after that.

PS next time i talk to the guy i'll see if i can get the copy of the service bulletin and i will post it here

 

[Faztbullet]

Re: Defective Carb help

There is a bulletin on this but most problem motors was fixed or repaired in 1980-81. This just doesnt suddenly happen unless engine was bought new and has set for 29 years!! If I remember correctly you have staggered high speed jets in this model do to this bulletin(all 3 are not the same). You are running lean do to a blockage in carb ,float levels improperly set,low fuel pressure or pullover passage stopped up and premuim fuel does not mean its ethanol free ,it must be posted at pump.

 

[HybridMX6]

Re: Defective Carb help

If it worked fine before and doesn't now, I'd suspect clogged carbs. If they were defective then they'd have been defective before also.

 

[mattsylvan]

Re: Defective Carb help

it hasn't been right since i got last year but this is good to know because he is going to check it out today or tomarrow and i tell you what he says. I dont know but i think he is still fixed on the defective carbs but i dont know yet.

 

[Silvertip]

Re: Defective Carb help

I agree that this is not a defective carb issue. It that engine required choking to get to high rpm it would have died from being lean long ago. This is simply a carb rebuild issue or a fuel pump/adjustment/delivery issue. And stop worrying about ethanol. We've used the stuff up here in the midwest for well over a decade and it is simply not an issue provided the rubber parts in the fuel system have been replaced with modern components.

 

[ezeke]

Re: Defective Carb help

There were several service bulletins dealing specifically with hestitation in midrange on some 1980 and 1981 70HP and 75 HP motors.

The defective carburetors were on 1981 and 1982 motors and were supposed to be replaced at the time of the service bulletin (#2058 November 1982) and are probably not what you have.

Service bulletin #2025, June 1981, specified a change in intermediate jets on specific carburetors found on 1980 and 1981 70HP and 75HP motors. This was in response to "Hesitation on Acceleration".

 

[mattsylvan]

Re: Defective Carb help

ok so your saying the it not a defective high speed carb it probably needs a rebuild or fuel delivery has a restriction in it. it at the mechanic right now but he said he was thinking about changing the orfice but that was when i first took it in but im going to call him on friday and see whats up. i will let you guys know what he says becuase im not sure if this guy is just taking me for money or if he is actually telling the truth. i thank everyone for helping me out in this little problem

 

[75-JOHNSON]

Re: Defective Carb help

ive also read up on these deffective carbs on a really old post on this site...but agree with the rest that if it was working before it is probably not a defective carb.

 

[mattsylvan]

Re: Defective Carb help

they called me today can they said i do have the after market carbs and they say that who ever rebuilt my carbs screwed up the jets becuase they just told me that they said he low speed was supposed to have a #16 in it and i had a #32 in there so I may have cought a break in the repair!!

 

[tx1961whaler]

Re: Defective Carb help

I'd ask the mechanic where he's getting the #16 from. The parts list at http://shop2.evinrude.com lists either a #32, #36 or #38

0323703 ORIFICE,No.36,20 inch transom. Early Production With Part No.389241,389242 Stamped on Body 75 Models Only 1 $7.25 USD Available

0320016 ORIFICE,No.32,15 inch transom. 75 Models Only 1 $7.71 USD Available

0323149 ORIFICE,No.38,20 inch transom. Late Production With Part No.391632,341633 Stamped on Body. 75 Models Only

 

[mattsylvan]

Re: Defective Carb help

hmmm good point i will ask him on monday becuase he is closed now