Yamaha Outboard Parts
Yamaha   Yamaha Outboard Parts
Yamaha Outboard Forum Yamaha Outboard Parts Discussion Forum Yamaha Outboard Parts Boat Parts Yamaha Outboard Forum Outboard Motor Parts Contact Us
Yamaha Parts
  #1 (permalink)  
Old 05-29-2009
Posts: n/a
Default 1994 130 carbs


My engine was running poorly at what I call "trolling speed". Liek when the engine is putting through a no wake zone. I will add that it ran great @ WOT and @ idle.

SO...I decided to clean the carbs. They did have some varnish and are now clean, floats adjusted (they were fine) new needles and gaskets.

Question. when I backed out the idle adjustment screws they were all @ 2 1/8 turns. The manual I believe calls for a max of 7/8. Seeing how the idel was fine should I put them back where they were? OR where the manual calls for? Or something else?

Also I did test run the boat (with screws @ 7.8) and it had the same coughing problem at trolling speed. I have read the manual on the 3 basic carb circuts and focussed on the BYLASS circut. I took the carbs apart again and cleaned again. Looks fine.

Should I be looking anywhere else?
Reply With Quote
  #2 (permalink)  
Old 05-29-2009
Super Moderator
Join Date: Dec 2009
Location: Lake Placid, Fl
Posts: 10,359

Make sure low speed jets in carb are clean. The 7/8 of a turn is the inital setting and may need to be adjusted but usually runs great at 7/8 to 1 turn.
Yamaha Outboard Parts
Reply With Quote
  #3 (permalink)  
Old 06-02-2009
Posts: n/a

Well I cleaned and adjusted carbs again. I started with the idele screw @ 7/8. I ended up back where it was at 2 turns out. It seemed to like it there better. Is that leaner or richer?

Should have it in the water for a test soon.
Reply With Quote
  #4 (permalink)  
Old 06-02-2009
Posts: n/a

2 turns out should be richening your low speed mixture. It sounds like you are compensating for a partially clogged low speed circuit which can be very difficult to get clean. No need to mess with float level any more. Use a strong carburetor cleaner in all idle/low speed circuit pathways and main jet and venturi and blow out with compressed air. Repeat 2-3 times. A partially clogged idle jet may run well enough at idle on a warm day, and perhaps not well enough for fast idle/low midrange. P.S.- you would not be the first to pull carbs off multiple times before getting them right...hopefully this helps your problem. Usually a weak/old fuel pump will cause a poor low speed running condition, but this would noticeably affect normal idle, not just fast idle.
Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 08:50 AM.

Outboard Parts

Other Forums
Mercury Parts
Suzuki Parts
Evinrude Parts
Johnson Parts
Honda Parts

Copyright 2000 - 2017, Outdoor Network LLC