1980 Evinrude 25 HP Stripped Bolt on Lower Unit

[111torrance111]

Tried a simple water impeller replacement and ran into a stripped bolt in the lower unit.

When removing a stubborn lower unit I put pressure the back nut and stripped the threads, now I need to replace it and it's stuck pretty good and need advice.

I tried putting two nuts on it and removing with the bottom nut, but the bolt wont hold.

I'm soaking overnight with some WD-40, but not sure if that will work.

Any advice would be good.

Jerry

 

[boobie]

Re: 1980 Evinrude 25 HP Stripped Bolt on Lower Unit

Post a pic of the problem.

 

[jb93]

Re: 1980 Evinrude 25 HP Stripped Bolt on Lower Unit

Here is a cut and past from an old Machinists Workshop article where they tested several options. Liquid Wrench is the best retail option of performance/price. 50-50 mixture of ATF/Acetone was the best overall. I believe you have to shake it once in a while as it separates, but it tested best. WD40 worst performer.


Penetrating oil . Average load .. Price per fluid ounce
None ................. 516 pounds .
WD-40 .............. 238 pounds .. $0.25
PB Blaster ......... 214 pounds .. $0.35
Liquid Wrench ... 127 pounds .. $0.21
Kano Kroil ........ 106 pounds .. $0.75
ATF-Acetone mix.. 53 pounds .. $0.10

 

[111torrance111]

Re: 1980 Evinrude 25 HP Stripped Bolt on Lower Unit

Had to have the bolt drilled out, once completed I replaced with new ($28.00) stainless bolt & reassembled. Everything worked great & now have a boat working great.

Thanks for the help.

Jerry