1977 25 hp 25702h

[Johnsonmitc]

I have a 1977 25 hp evinrude. It has a jet foot on the motor instead of the standard lower unit. The model is 25702H. I had the motor out yesterday and was running at WOT. I was at Wot for 15 minutes, and motor stopped on a dime. I couldn't roll over motor by hand clockwise so i thought i locked it up.... i played with it for a minute and noticed I was able to roll it in reverse though. I was able to make 10 revolutions backwards but it catches on something rotating forward. I removed spark plugs, and kept trying to move flywheel by hand. After some playing, the motor started allowing me to rotate forward as well, then i couldn't roll it in reverse... after continued working of flywheel, i have gotten it to hang up in multiple locations in both forward and reverse.... any thoughts?? I removed the intake to see if i found any broken pierces by connecting rods, bearings, cam... i didn't see anything that jumped out at me, but hard to see much... I'm hoping someone can help me from here.. have not been able to look at cylinders yet, and have not split the motor yet... thanks in advance!

 

[fdrgator]

Remove the flywheel for inspection. Sounds like something came loose in there.

 

[Johnsonmitc]

I just removed the flywheel. I don't see anything out of place. the magneto assembly looks like all is intact. Do i need to remove anything else or go any deeper?

Remove the flywheel for inspection. Sounds like something came loose in there.

 

[fdrgator]

Well then it's busted inside the lower unit or inside the powerhead. Lower unit is easiest to remove to decide which one is the problem.

 

[Johnsonmitc]

Ok. Thank you! I'll review when i can get back in the garage! Thanks

 

[fdrgator]

I forgot it is a jet. Don't think I've ever seen one down here in the swamps. Probably need them though.

 

[Johnsonmitc]

Update... i ended up dropping lower unit cause it was going to be easiest. Still was binding up. I then pulled the head. Seen some slight marks on cylinder walls but nothing bad. Decided to pull the power head. I ended up splitting the motor. Found my lower crank bearing had exploded. Not the most fun part to get to but at least i found it. Thanks for the help!

 

[Johnsonmitc]

Just getting all the parts that i needed in the mail. Looking for the torque specs on all bolts to this motor. Need to change crank, head gasket, water cover gasket, intake gasket so pretty much need specs for all. Thanks in advance!