Rear Hatch Rust

[Tim 76' 280Z]

Well I got my Por 15 products ordered! I got Por 15 silver, Marine clean, metal ready, and white seam filler. I totally cant wait!!! I got enough to do my floor boards, rear hatch, and battery tray!!! The local Napa store had Por 15 but they only had a pint of black and none of the prep products so I just ordered online.

[Tim 76' 280Z]

I know that I am getting away from the rear hatch when I bring this up but I do not know where to start with this... The PO had sprayed black primer on the floor so under that is rust. It does not appear to be rusted thru. What should I do first to prep for the POR products??? I can take better photos if needed.....

Edited May 4, 2009 by Tim 76' 280Z

[Zak's Z]

I would scrape that black coating off first. It also looks more concerning closer to the seat. In the pic that looks like it may be a bit worse that surface rust. Since its the floors I would get all that rust off first. To do that, I would take a wire disc on a drill and just hit that area closest to the seats to see how bad it is. If its just surface rust, you can clean most of it off then prep for your POR application. If its worse than that, you really need to cut the rusty metal out and replace it. How does the underside of your floors look like?? How are the supports that go along the floors, and the frame rail area too?

[Tim 76' 280Z]

Ya it does look like more then just surface rust. The bottom of the floor looks great and so does the passenger frame rail. Im just scared that what is left of of good metal is so thin its going to have to be replaced. Also the only support I might have is the undercoating, but the floor feels to strong for that to be the case. The strange thing is on the drivers side its the other way around. Frame rail has about a 6 inche area rusted out and the floor is in great condition.

Should I take the sound proofing material up?

Edited May 4, 2009 by Tim 76' 280Z

[Zak's Z]

Tim, you really should deal with the rust in that area. You may discover its not that bad, or if its worse than you thought. I picked up a Z with a friend last year and I took a little pick with us and I got under the car after thinking the metal was pretty good. Sounded good, looked good, etc. When I jabbed that little pick into the floor, it went through. It went through the supports, frame rail and rocker too.

I would take that soundproofing stuff off, and find out how bad it is everywhere so you can assess your best plan to deal with it. You cant put POR15 over it and forget about it.

[Tim 76' 280Z]

Oh Im not just going to just POR it and forget it. Im just totally not looking forward to uncovering the damage because im not a welder and not all that hot with any other form of body work.:paranoid:

Is that stock sound proofing material hard to remove?

[darom]

<i>Is that stock sound proofing material hard to remove?</i>

I used a chisel and a putty knife on my 76 to remove the factory insulation. Some of it came off easy. I didn't have to dry ice any pieces or use a heat gun. I did feel my right hand got twice as strong after this procedure :-)

[Tim 76' 280Z]

Well it was driving me crazy so I went out to see if the floor was rusted thru or not. Didnt have time to do the whole floor but the section I did do looks good so far. Just hope the rest of it is good!

[Zak's Z]

Ahhhhh.. thats a good feeling. Hopefully the rest will be ok also.

[Tim 76' 280Z]

:bandit:Dude im so happy and feel better about the car as well!

[=Enigma=]

In answer to some of your questions earlier question, yes you can paint POR15 over other coatings such as scuffed paint to provide a tough exterior finish, however unless it's plainted directly over clean etched metal, or rusted metal, it will not stop or prevent rust from forming. When painted over rust, (preferably cleaned up rust) POR15 will stop it from spreading. When painted on fresh metal it will prevent rust from forming.

Also, you can topcoat POR15 with a thin drycoat of your favorite primer as long as you do it while it's still tacky, meaning that is provides a slight resistance when you drag a finger over it, but is not sticky. With this done, you will then be able to apply a regular topcoat on it whenever you're ready. The same is true when applying a second coat of POR15. Just apply it while the previous surface is tacky. Usually between 1-1.5 hrs after coating. Time varies based on atmospheric conditions. If you let it dry completely, you'll need to scuff it up with at least 600 grit before applying a second coating of POR15 or another topcoat. One exception is the TieCoat primer. Note that their topcoatings such as BlackCote and SilverCote can be applied to a dry surface within 24hrs without the need for scuffing, but any longer than that and scuffing is recommended.

Always make sure that the surface to be coated is clean and etched chemically or scuffed with at least 600 grit to provide enough mechanical grip for the POR15. Also note that this stuff goes a looonngg way. They recommend at least 2 coats 2 mils thick each if I recall correctly. I did my entire gas tank with 2 coats using one of their little 4oz cans, then topcoated the bottom with their BlackCote product which is slightly less glossy than the POR15 coating and not sensitive to (UV) sunlight.

Final word of caution, be sure to wear gloves and any porous surface you don't want this stuff on. If it gets on your skin and has a chance to dry, you'll be wearing it for a week or more until your skin cells shed off. Take my word on this.

[Tim 76' 280Z]

I worked on the floor some more tonight and this is what I got....There is a dime size hole right in front of the seat. That’s the worst part of the whole thing so far. Next is to take the seat out and continue back.... But the worst is over because the rest of the floor is in better shape… I think…:pirate: