1986 90hp johnson:It wount speed up at full throttle! helpp

[johnson426]

hey guys the outboard used and the previous owner claims it was winterized and looks like its in good condtion but I installed it on my boat and when I give it full throttle it barely goes fast so I pulled the cover off to make sure the throttle was opening up all the day and they were and when I spray carb cleaner into the cylinders it doesnt make any difference except the top right one and the boat seems to get louder and go faster. Could it be the carb is gummed up ? should i pull it off to clean it ? and is there any link n sync that should have been done when i installed the new outboard ? thanks guys!

 

[jtexas]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

Here's the thing about spraying carb cleaner down the carb throats: it goes right past the jets and other orfices that need cleaning, right though the manifold into the crankcase and cylinders, where it does what it's designed to do, which is strip the lubricating oil right off your crankshaft, pistons and cylinder walls.

If you wouldn't run your motor without oil, don't run it on carb cleaner.

Check to make sure your timer base is moving all the way to its stop up under the flywheel when you throttle up.

Carb rebuild is generally just a good idea when you buy a used motor especially if you've never even seen it run before. Water pump, too.

You'd need the manual for the step by step in the link & sync including adjusting the throttle cable. Highly recommend you go ahead & order one now, will save you lots of future money and aggravation.

Your question is kinda hard to read. you might get a better response if you'll try using "sentences" and "punctuation".

 

[johnson426]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

Sorry I apologize, I was in a rush but I will check the things like you said! is it worth it try using that sea foam to clean out the system ? based on my knowledge I believe its not getting fuel into that one cylinder. thanks!

 

[emdsapmgr]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

Also check to make sure you have strong spark on all 4 cyls. Use a spark checker or an inductive timing light.

 

[AEROCOOK]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

Sorry I apologize, I was in a rush but I will check the things like you said! is it worth it try using that sea foam to clean out the system ? based on my knowledge I believe its not getting fuel into that one cylinder. thanks!

If it's not getting fuel into 1 cylinder it is quite possibly a clogged orifice/gallery/passage in the carb. Spraying carb cleaner into the barrel of the carb will make it "look" clean as a whistle but will not fix the problem, the carbs need to be removed and soaked to clean out the junk inside that you cant see.
If you continue to run the motor with 1 cylinder not getting fuel and more importantly the lubricating oil mixed with it, you WILL ruin the motor.

 

[johnson426]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

ok thanks for the help guys I really appericate it! I think there is spark, since when I spray carb cleaner it opens up and moves like its suppose to. I guess im gonna have to take the carb off and clean them out. One of my buddy mentioned try using sea foam to clean it out, is it worth trying that or just pull the carbs off ? ( sorry I dont have that much experience with boats so I dont wanna start taking things off) thanks for all the help!

 

[AEROCOOK]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

ok thanks for the help guys I really appericate it! I think there is spark, since when I spray carb cleaner it opens up and moves like its suppose to. I guess im gonna have to take the carb off and clean them out. One of my buddy mentioned try using sea foam to clean it out, is it worth trying that or just pull the carbs off ? ( sorry I dont have that much experience with boats so I dont wanna start taking things off) thanks for all the help!

The carbs need to be removed and soaked to properly clean them, I dont think anyone on this site will disagree with this advice.

 

[jtexas]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

You really can't clean a carb properly without taking it apart. Seafoam is great stuff, it keeps my carbs clean, but I don't think it's a strong enough solvent to clean out the kind of gunk that can accumulate in there.

Don't be intimidated, these carbs are suprisingly simple devices.

 

[emdsapmgr]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

When you get the carbs apart for cleaning, you can also try any aerosol carb cleaner. It works great on cleaning the passages in the carb bodies.

 

[ezeke]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

Watch your timing advance while someone moves the control arm; make sure that it is working properly.

 

[johnson426]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

ok will do! thanks alot guys!

 

[Brew2]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

If you have the black "plastic" like carb bodies...do not "soak" them in carb cleaner as it will damage them. Use an aerosol carb cleaner, then follow up with compressed air to clean the carb passages.

Also install carb kits (ie. new gaskets, needle valve, float) while you've got the carbs apart.

Finally, make sure you get that manual. Will make your life a lot easier when doing stuff like this.

Good luck!

 

[johnson426]

Re: 1986 90hp johnson:It wount speed up at full throttle! helpp

hey guys, figured out the problem. It was the carbs clogged so I went ahead and took it off, which was easy (15mins) cleaned it and aired it out and took it back on the water and she runs greatt..thanks for all the help!