1993 Johnson 60 hp not running 4-6000 rpms

[cat-n-tenn]

I have a tracker 17ft alum. boat semi v front has a 13.25x17 prop. Prop looked like it had a rough life, and i heard that if a prop hits something it can mess up something inside lower unit. Is this true? <br />Also i loosened the vent completely on the fuel tank an it seemed to help a few rpms.all i can get is about 4-4500, i think this boat should run in mid 35-40 mph but all it is running is 20mph. Also the motor revs nice when it is not under a load , but when you put a load on it at 4000 plus rpms it just dont want to run up there.<br /><br />Here is what i changed on it when i bought this week new plugs,fresh fuel,sharpened prop.<br /><br />PLEASE HELP IF YOU CAN. THANKS WILLIE

 

[rickdb1boat]

Re: 1993 Johnson 60 hp not running 4-6000 rpms

Hey Willie,<br /><br />Can you give a little history on the motor? Did it sit for any length of time without use? Did it ever run good for you? Sounds like you just got it???? A little more info, please. Odds are you are not running on all 3 cylinders or you have a clogged up carb somewhere down the line...Are you using 50:1 mix or does it have VRO hooked up(Oil injection system).?

 

[cat-n-tenn]

Re: 1993 Johnson 60 hp not running 4-6000 rpms

I just bought it one of them deals i thought.lol. But i would say it sat for a while and probaly pulled behind house boat.It has never ran good for me but seems to run better than when i first bought it but not much.the vro was unhooked when i bought it so i just mixed it 50;1 myself.How can i check to see if carbs are clogged up or if i am not running on all 3 cylinders? thanks

 

[rickdb1boat]

Re: 1993 Johnson 60 hp not running 4-6000 rpms

As far as the carbs, the only way to really check them is to take them off and clean them out. You could take it for a run or run it on muffs, shut it down and check the condition of the plugs(Wet or Dry), but it would be best to clean them if you are in doubt. As for spark, head to the auto parts store and get a spark checker. (Cheap) You can check for spark by just turning the motor over using the starter...

 

[cat-n-tenn]

Re: 1993 Johnson 60 hp not running 4-6000 rpms

I had checked the plugs the other day an they were dry an black.the carbs were only opening 3/4 way open so i opened a lil more to wot. may of helped but not much if any.drained the lower unit an it was black as coal. just trying to remember all that i found.

 

[cat-n-tenn]

Re: 1993 Johnson 60 hp not running 4-6000 rpms

So is there anything in the lowere unit that u think could cause this or the prop ?