1987 Johnson 90HP Crossflow Carbs

[etracer68]

Well after solving my overheating problems, with new pump, hoses, and stats, I wnet to the lake today, and the motor started and purred like a kitten. After I restarted it later that day the idle was up about 200 rpm, and started to not idle well, and was killing. I stayed out on the lake, and enjoyed the rest of the day, and came in on my trusty 4HP. I figured its time to rebuild carbs. Carbs have not been off in years, and was stored with fuel in bowls. I have rebuilt all kinds of other carbs before, are there any tricks to these carbs? I ordered two kits today from iboats.

 

[keykev]

Re: 1987 Johnson 90HP Crossflow Carbs

I just cleaned out the carbs on a 1988 88 hp evinrude i picked up that sat for 10 years and were loaded with crud. the carbs are simple enough, i removed the floats and any jets that would unscrew and cleaned them with carb cleaner and compressed air. the motor runs good now and idles smooth. my seloc manual said to set floats level with carb body but they were slighty up when i took it apart. i set them level and ended up taking them off again because the motor ran rich. i reset them back up to solve the problem. hope this helps, keykev

 

[AEROCOOK]

Re: 1987 Johnson 90HP Crossflow Carbs

Check the parts schematic in the BRP catalog to see the location of all of the jets. When I cleaned the carbs on my 1988 110 Jonson last year, I didnt even notice the jets that are screwed into the plastic float boals (there are 4 of them there according to the catalog) Long story short, I had a studdering problem just off idle when accelerating and after reasearching possible causes I discovered that I had failed to clean the jets in the plastic boals. I took the carbs off and cleaned them again this past weekend making sure to do a complete job this time. FYI you should also remove the 4 cover plugs (2 per carb, item #2 in the parts schematic) to clean the orifices under them. It's an easy job, I think it took me an hour and a half or so.