Hello everyone, I ended up purchasing a used bottom end on eBay for my 1994 Yamaha Timberwolf 4x4 since my engine needed a new crankshaft and I wasn't feeling up to splitting the case. What I received today was different than the pictures in the listing - the connecting rod, crankshaft, balancing shaft and bearing have quite a bit of rust on them; none of this was apparent in the sellers pics. The gears appear fine but there also appears to be some "gunk" in there. My question is, is there any way to remove this rust without splitting the case? I was thinking of spraying a corrosion inhibitor spray in there over the next several days and then trying to figure out a safe way to flush all the crap out. What would be a good "flushing" chemical? The crank does spin very smoothly so I am really hoping to avoid splitting the case.

 

We have the information you seek on the ATV Connection homepage, here:

https://atvconnection.com/articles/a...-removal-help/

 

Great, thanks guys! One question, since I don’t have the case side covers installed and the evapo-rust will leak out, would it be safe to just dunk the whole bottom end in a Rubbermaid filled with it?

 

From the team: Absolutely, it won't harm seals or dry out rubber so using a plastic container to submerge the components to soak in would work just as well.
Best of luck!