Thread: 1998 50hp evinrude outboard

I think what I would do is find the manual for that outboard and look at what the factory recommended for breakin and follow there guidelines.

When you get your block back, get some heavy duty white paper shop towels, little diesel fuel. Wet your towel and scrub the cylinders real good 3-4 times. Wipe with clean paper towel until you have no residue. Then scrub with dawn dish washing detergent, wipe dry. Then put a slight coat of engine oil on cylinders and wipe dry with towel checking for any residue. Once completely clean I will dip piston and rings in oil and let drip dry before putting on ring compressor and then install. Double up on oil in gas. Hook up and run at idle about 5 minutes then shut off and let cool down. Do this 3-4 times. Take to lake and run at idle until it warms up, then put in gear and idle around a little to make sure everything is ok. Then go up to about 1/2 throttle run it a few hrs 3-4 just running up for a few minutes then slow it down for a few then back up. This will help seat rings. Don't run full throttle for an extended period until you get 10 or so hr's on it. Run at least 1 tank through it with the heavy mix. When you go back to normal mix put in a new set of plugs.

I will do as you guys suggest, cause I have never rebuilt an outboard this far before so im into something new.have not got the block back yet. so Ill take it real slow on this job, and check my self to make sure its going back together like its supposed too. thank you guys for all your input,you guys dont realize how much it helps thanks.....jerry

Up date on Power head rebuild, the powerhead that i had was not able to bore out 60 thou,is the max they can bore one,and it still would not get pitting out and the cost of replacing with new sleeves were not worth the cost.Bought a rebored powerhead and matching pistons with rings and a gasket set for this 50 hp motor.Im now in the process of cleaning the crank bearings before I lay it in the power head.


the total cost for this rebuild with me doing the labor,will be a little over 600.00 dollars If I am very careful of doing this right I will have a very good outboard that serve me for a long time. Question the crank looks very good,but has any one polished the rod journels,and how is it done....thanks

Should have known better,was going to clean off the crank and free up the roller bearings before i set it on the power head. had both rods connected to both pistons,and rings put on both pistons. used carb cleaner to free up roller bearings on crank forgetting about the seal that was on it,it was the old one but was in very good condition,until i sprayed it with carb cleaner,should have known it would do that after it melted my rubber gloves that i had on.Will now have to wait till my gasket set comes in and see if it is included and use that one.maybe that was for the best, needed to replace it any ways,but i lernted me something today.dont go spray that stuff just anywhere you could mess up things,if youdont know what your doing....

Don't use that stuff to clean anything other than carbs. Get non floro acted brake clean and follow that with starting fluid. Break clean will clean but leaves a residue, the starting fluid will cut that residue off.

Got both will do that tomorrow,get that crank clean and ready then back to the youtube training videos till the gasket set comes in.thanks for the info.....

Up-date,Im sure glad Im not depending on making a living both fish,and fixen outboard motors.Boy am I slow but got the power head all cleaned up,installed the piston rings,and in the holes. put plenty of assembly grease on roller bearings on both piston rods. Installed them on the crank at the torque it calls for. Put the intake on the block and torqued it down making sure the crank bearings were seated on the pins right,so I would not break something when the intake was mounted.Got the head installed and torqued down.Just waiting on a lower oil seal that needs to be installed in the crank lower cover plate,Boy have I lernted me something,Now waiting to see if my ability to mechanican is any good.Caint believe this started in Feb.and still not got it running yet,Am I the only one this slow.....