Using fillers on engines.

Some of the early engines used a clay like filler prior to painting. Most of the time, the early fillers would crack and fall apart.

Today, there are several types of modern fillers for various applications.

I have used Bondo, but I'm not very happy with it as it doesn't take heat well and tends to crack.

What other fillers have you other folks used while restoring engines? I'm looking to simply fill in the rough casting, but I'n not looking for a smooth "auto body" finish as this was not original.

Any thoughts?

Bill: In the automotive paint world, a sandable primer is available. Several coats may be required to build up the the desired finish, of course sanding between each coat. I don't know how this would work for deep pits, though. Seems like JB Weld or any of the epoxies would fill in pits if the surface were prepped right.

maybe cream fiberglass?

hello where I work we have many metal parts powder coated which is baked on. for filling in these aplications a product called lab metal filler is used.it is avalible at the eastwood co. www.eastwoodcompany.com. I havent tried it on engines but it sounds like it would take the temperatures of an engine. good luck