1994 Johnson 90 V4 - Boat Won't Plane

[sunbird170]

A few weeks ago, the outboard wouldn't run at idle and was smoking like mad. Mechanic at a local marina fixed that problem and i'm guessing made other adjustments. Well now the outboard starts up like it did when i got it, idles fine, however, with the throttle control all the way forward, the boat will not plane out like it used to. even with all the weight at the front, it still takes a good 3 or 4 minutes to get on plane. The RPMs from dead stop go to about 3200 and by the time it gets on plane its sitting at about 4200 but won't go any higher. This boat used to cruise at around 30-35 mph but now will only go 25. Are there any adjustments I can make to get it back to its old self? The mechanic doesn't remember what adjustments he made on my boat since it has been a while. I did put the throttle cable back to what appeared to be its original position (could tell by the color of the threaded rod on the cable) Could it be the shift cable? The WOT screw? The roller that rides on the cam? It just seems like the carbs arent opening up enough to let the engine make some power. About how many threads should be showing on the end of the WOT screw (the end without the screw head)? Thanks for any help!

 

[tashasdaddy]

Re: 1994 Johnson 90 V4 - Boat Won't Plane

have you check compression and spark? do you have a manual? if not quit screwing with it. it can take far longer to figure out what some did, that did not know what they were doing.

 

[ezeke]

Re: 1994 Johnson 90 V4 - Boat Won't Plane

Start by taking the cover off the carburetors and moving the throttle all the way forward to see exactly where the throttle plates in the carburetors are at WOT. They should be level and perfectly synchronized.

You may need to rotate the flywheel to get there with the engine off, so take the plugs out so that you can move the flywheel easily by hand.