POR15 Prep

[Clover]

Hey team,

Doing an IRS and got a used differential and knuckles for it. I have seen others who painted the cast iron part of the rear differential housing with POR15 and thought it looked great, so I bought some POR15, metal degreaser, and metal preparation to paint the knuckles and differential housing myself. At some point, something was leaking oil was above my rear end and the differential had a good bit of oil drip onto it and run down the housing. Plus, when I pulled out the axels, some of the differential fluid ran down the side of the case.

Last night I got the chunk removed from the knuckles and today and I have been trying to get everything clean for the POR. I have spent a couple hours and two rolls of paper towels trying to degrease the dif housing and I am starting to wonder if I should keep at it or call it good and just go to the POR once it is dry. I am kind of at a point of diminishing returns where I don't seem to be getting a ton of grease out anymore but I would not call it perfect either. I wanted to check with the community how clean you need to get the surface before applying POR15. The stuff is made to go over rust and I am starting to think I am over doing it with the cleaning and I am now wasting time.

What do you guys think? Should I spend more time cleaning, then do the metal prep solution, then POR or should I stop fussing and apply the POE15 and call it done. I want to do it right the first time, but I also think I may be wasting time to try to get it perfect before applying paint intended to go over the top of rust.

Thanks, I have never used the stuff before.

[JohnK]

It it's surface rust that you're seeing, don't worry about it - just paint over it. If there's still grease residue, you definitely want to get that off before applying POR15.

[BadAsp427]

If you still seeing Oil/Grease, perhaps a pressure wash with some good degreaser on it will help. POR15 won't stick very well if there's any oil on it.

[Clover]

I just kept at it with the degreaser and now have the differential ready for POR15, which I will apply tomorrow. I guess this is my first lesson of "Looked nice on the forum, why not." Now I know that one little photo made up a full day of tedious work and you guys made it look easy. Oh well, I bet it will be one of those details I look at when I am done and I will be glad I did. Everything else under the car is aluminum or black. With the differential covered, it will all go together and look finished.