Has anyone had any long term luck with rattle can engine paint. How long do they typically last? What brand paint?

 

Yes! I use the VHT paints from the Irish parts store. I use black, red and silver. The red/black enamble works great on the cast iron block. The silver not co much.

I painted the valley of my 7.3 in silver to help see leaks better. I also painted by hot and cold I/C pipes silver. The first time I used a degreaser the silver was gone.... the rest was just fine.

I might could look at a different silver, but that's my experience.

 

VHT for me on all engine projects, same for the machine shop I used to work at. Just be sure the block is thoroughly degreased and prepped properly - otherwise nothing will stick for a long time. Also try to keep from causing any sharp or unfeathered edges as they can provide an area for intrusion beneath the paint and cause lift-off. On bare metal try to avoid brake cleaner, it can lead to flash corrosion.

 

How are you preparing and are you using a primer? How long does paint
hold up? I'm going to be installing a new oil cooler soon and wanted it painted before installing, will also be pulling engine later this year to replace oil pan and plan on having engine painted when it's out. Just want to get it done right the first time.

BTW, thanks for the help on Excursion door shipping from Texas, still working on that one.

 

I wouldn't go painting something like an oil cooler just because the paint can impede efficiency, as can any other coating. While minimal in impact, it's still an issue. I work mine hard in hot AOT, so I want maximum efficiency.

My prep steps:

- Knock off all loose debris with wire brushes of varying sizes, blow clean with compressed air. Avoid areas that are greasy and grimy as the brushes will just spread it all over the place. This step is interchangeable with the following regarding order to follow, depending on the condition and nasty-ness of your components. So you could do the degrease first if yours is nasty, then knock off the loose debris after.
- Wash with quality degreaser such as Gunk or Simple Green, agitate with stiff bristle brush. Rinse with water and repeat until clean
- Final prep immediately before painting, wash with soap and water, rinse with water. Air or compressed air dry.
- Mask off any and all orifices, holes, ports, plugs, etc. Paint in the wrong areas can cause sealing issues, or equipment failures if the paint flakes off and gets into a pump, passage, etc.
- LIGHT coat of VHT primer, and by light I mean you should still see metal showing through faintly. Wait 20 minutes, reapply another LIGHT coat. Let sit another 20 minutes, apply MEDIUM coat. Let sit for about 30-40 minutes and check coverage. If it's satisfactory, continue to engine enamel paint. If not to your liking, reapply a light or medium coat depending on how much more you need to cover up.
- Apply paint in same manner as primer, same coats and wait times until final desired result is achieved. If you want, follow up with a coat of clear afterwards per can instructions (I don't bother with clear, so I don't have any advice on it).

Properly done, the paint will last many years. Improperly done (such as edges that allow oil intrusion beneath the paint, the paint will last maybe two or three months before it starts coming off in flakes and chunks. The Jeep block I painted last me 6 years and was still going strong when I sold it, and that thing was offroad and in the mud nearly every weekend. Pressure washing, road debris... it didn't care. The Chevelle block I rushed and didn't blend my edges. First oil leak ended up peeling the paint after about a week as it got underneath and caused lift-off all over the place. That block has more bare metal than paint on it now.