Painted windage tray & sump?

[AW111]

The engine I'm rebuilding (4AGE 20v) has a windage tray that was originally painted black, as was the interior of the sump.
The paint is somewhat tatty around the edges of both windage tray and sump - would engine enamel be suitable to touch it up?
If not, what to do - use a different paint (which?), or just clean up the tatty edges and say it will be oil-soaked anyway?

[paintman]

I would advise against painting the inside of a sump or the windage tray due to the likelihood of the paint coming off & blocking things.

[CrutyRammers]

Engine enamel would be fine for the outside.

[Happy Jim]

Why on earth would anyone paint the inside of a sump? it's never going to rust and the only thing that is likely to happen is bits flaking off and gumming up the pump - nuts

[Inline__engine]

people reportedly paint the inside of blocks for drain back and to stop small silica particles coming out of the casting because it can be difficult to remove 100%. done properly it works but i wouldnt feel comfortable on an engine that is going to run longterm. they say you arent supposed to sandblast the inside of the sufaces of the engine e.g. block, sump, valve cover, inlet runners because you can never every single spec of sand out as it gets partially emebedded and comes loose over time

[tr7v8]

Inline__engine said:

people reportedly paint the inside of blocks for drain back and to stop small silica particles coming out of the casting because it can be difficult to remove 100%. done properly it works but i wouldnt feel comfortable on an engine that is going to run longterm. they say you arent supposed to sandblast the inside of the sufaces of the engine e.g. block, sump, valve cover, inlet runners because you can never every single spec of sand out as it gets partially emebedded and comes loose over time

I used to paint the inside of blocks when I rebuilt them. A. to speed oil flow back to the sump. B. to lock in any detritus. And C. Because if you get a run bearing it makes cleaning it all up so much easier.
I used to use BondaPrimer, never had it flake off or cause any issues. And at one point C. above was important because we were doing a set of bearings a weekend. Eventually we sorted the oil surge problem that was causing it. But took 3-4 sets before we cracked it.

[one eyed mick]

I a previous life I rebuilt many large [10litre] air cooled diesel engines , the inside of the block was painted with some thing that looked like red oxide to clean blocks we boiled them in a caustic solution even that would not remove it ,later research led to finding GLYPTOL[?] it used by our American friends to coat the inside of big V8 's ,surface has to be dust ,oil and grease free but it sticks like poo to a wool blanket , ,its expensive £ 50 a litre but can be brushed or sprayed I got some from Frost restoration