Review on Black POR-15 Patch - 4 oz Filler & Seam Sealer with Ultimate Adhesive Properties - Repairs Holes, Cracks in Steel, Wood, and select Plastics - Reinforces Weakened Metal by Michael Colley

I have used POR-15 in the past and find it to be an excellent product when used correctly. I painted a 300 liter fuel tank in a boat with POR-15 paint and the tank came out fantastic. The boat is 1978 and the fuel tank is still in the boat, looks great. So what happened I found 3 holes in the diesel oil pan on another boat. This is the Mack E7M which is no longer in production and parts are becoming increasingly difficult to find. What to do? Spending $10,000 or more to remove an engine and hoping to find a new pan? Even if I find a new oil pan, should I return that old motor knowing there are virtually no parts? The POR-15 patch comes to the rescue. I used a black stain, but I probably should have used a gray stain with metallic scales. However, the patch worked. It even keeps cold at 60psi and hot at 50psi. What I did: Bought a paint set in addition to the patch. This kit contains an alkaline degreaser, a primer, a small can of POR-15 paint, a pair of gloves and a foam applicator. I bought the kit to use a degreaser and primer and maybe touch up some paint. It turned out that lying in the hold, the plaster could only be applied with a thick rubber glove. I also used some matte fiberglass material but I didn't need it and in hindsight I regret it. Step One: Dilute the degreaser, wire brush to remove loose rust, wipe clean, then rinse the area to be treated with the degreaser. Step 2: Rinse the degreaser thoroughly with fresh water. Step 3: Dry thoroughly. Step 4: (for bare metal): Apply primer. Step 5: Apply to the patch to the desired thickness. The curing time is 4 days. It's long but worth the wait. POR 15 is not a rust converter. It is a urethane impregnation that cures to a very hard surface and adheres very strongly to etched or rusted surfaces. It stops rust because it creates a watertight and airtight bond with the rusted surface. Curing speed is slower the thicker the coating, but moisture will speed up the process as this is a urethane based product. It is very important that your surface is properly prepared and completely dry before applying the product. This tube of band-aids saved me thousands of dollars.