I don't know the difference between the different types of bondo, so I was wondering what specific type of bondo I should use to fill in pin holes in some of the metal in the enginge compartment before painting over them?

Allmetal. It's a metal filled epoxy filler that doesn't absorb moisture.

I'll get flamed for this but I would say the cheapest stuff you can find.

Paul

Go with an aviation grade filler---it is called featherlite--best thing is it is flexable, so it won't flake off.

This stuff weighs 1/3 of regular bondo--go to :www.aircraftspruce.com

and look up in the composites section--they also have a great primer called---what the hell is that name??? I cannot remember, but go on to the site. That stuff, ohhh "superfill" this stuff will fill in imperfections for u--no glazing and it is compatible with all paints..

Good luck!!!

I also like the US Chemical All-Metal. It's not the cheapest, but doesn't shrink and sands pretty easily too.

What about bondo brand body filler? Also, do you prime the metal first, then put the bondo on, or do you just put on the bondo then prime it?

HELL NO-DO NOT PRIME FIRST!!! bare matel only--and "rough" at that--it needs roughage to really get a clamp on the steel!!