So I cut out the rust in the floor pan and welded in new sheetmetal, but now what do I do with the inside area where the patch is?

Also, if using por 15 in here, how do I clean it and "rinse with water" as per the instructions? I dont know how you rinse inside the car.

I was thinking about using por 15 inside the fender, can this stuff be painted over small amounts of undercoating? Pictures attached.

Thanks for the ideas@!!!

The floorboards of a Z typically have drain hole closed with rubber plugs. If your repairs have eliminated the drain holes, you may be limited to sponging out any water used to neutralize the Metal Ready or similar acid wash prep. Be sure to get everything VERY dry (as in heat gun, hair dryer) before painting with POR-15. The inside of the fenders are best totally cleaned of undercoating or other stuff before painting with POR-15. Scrape all the big stuff off, use a wire brush on a drill motor for the leftovers. You are already making a significant investment of time, don't rush or shortcut something as easy as the inside of the fender.

Jim

For the fender - Get a gallon of Mineral Spirits or Kerosine.... or for that small an area get a gallon of Diesel Fuel {which is about the same as Kerosine}... Soak the undercoating down and scrub it with a ScotchBrite Pad - it will wash right off.

FWIW,

Carl B.

thanks guys, my drain holes are still there, so no problem there, will take you advice on making sure it is completely dry. How long can I wait in between the metal reddy and the painting of POR? I didnt see anything in the instructions. Will try the two methods above for the fender. Thanks again!

W

The length of time to dry will depend on several conditions.

Mainly, if you have any overlapping panels where the capillary

action of water will draw the water in and be reluctant to let it

evaporate quickly.

As already said, use a hair dryer to heat all the metal in

question quite warm for "long enough".

There is no required waiting period defined by the manufacturer

between processes.

when they talk about rust free calif cars, i think they're referring to so cal cars. over 12 years ago i bought a 78 280 in santa rosa

and the front hinge area and rocker dog leg was rusted out. its those damn rainy nor cal winters. check your front hinge area for rust.

My Z is from Santa Rosa originally, moved to Anaheim. Only rust i could find (except small quantities of surface rust) was drivers side floorboard. Was rusted trough.

I don't know if anyone else would see this as a valid solution since it is a different product but I decided to use rust bullet on difficult to prepare interior surfaces of my car. However I have to wonder since rust bullet dries the same way POR 15 does (VIA moisture) would it work better if one prepares the surfaces in a similar way to what is required for POR-15?

Mike