1985 evinrude 120 hp v4 rpm go up and down then dies

[slim433]

hi guys i have a problem i need some help with we took the boat out and after about 30 mins or so the engine started to dog down and then back up and back down it will do this for awhile then die . i am not running at wot only maybe 1/2 to 3/4 throttle and if i back it down to just over idle for a few mins it will rev up again for afew mins then start up again . we just got this running last week with your help the compression is good plug were new . there is alot of dirt showingin the new fuel filter i installed and the primer bulb is staying hard bumbing the choke doesn't seem to help or hurt went it starts doing this . if i ran the boat at about 20 mph it seemed to work ok for a while longer while tubing the kids around . any help please

thanks
slim

 

[slim433]

Re: 1985 evinrude 120 hp v4 rpm go up and down then dies

forgot to addthat the pee stream looked good for this motor it was cool or cold at idle and running the hotest it got was bath water warm. and with the cover offi could lay my hand on the heads and let it there it was hot but nit burn u hot. thanks andi hopeu can help me out.
thank you
mike