18 hp evinrude locked up marvel mystery oil?

[Randaln]

Got A 18 hp evinrude I took out of storage and it seems to be locked up it’s in neutral
What do you guys use to unlock or free up a piston THANX

 

[nytebyte]

I have used Kroil and that did the trick but I have heard marvel oil mixed with acetone 50/50 is also good. Might have to drop your lower unit to make sure thats not the problem.

 

[DaleH]

FWIW a 50:50 mix of acetone & automatic transmission fluid (ATF) is the BEST penetrating solvent evah ... but you might have more serious issues ...

 

[DaleH]

FYI, here's the link to making your own:

https://www.tinboats.net/threads/homemade-penetrating-fluid-the-best-you-can-use-diy-too.39672/

 

[MrGiggles]

I don't think it makes a lot of difference. Any light oil will work, MMO, diesel, PBlaster, WD40, etc.