15 votes
Accepted

Why has white powder formed on metal parts after cleaning with degreaser and what can I do about it?

Believe it or not, that is corrosion. You are correct in your assumption that the Valve Cover is certainly cast aluminum. Aluminum can be damaged by many de-greasers that are too aggressive. This ...
Jeep Cherokee Rescue Society's user avatar
6 votes
Accepted

Safely washing engine bay of Ford Focus

My view on cleaning engines is that they are probably designed to get wet. At least wet in reasonable ways – rain while the hood is open, splashes from puddles, water that makes it through the ...
dlu's user avatar
  • 14.5k
3 votes

Hot bath for aluminium engine block and heads

Get a degreaser that will only affect grease - then you won't have to worry about the aluminium. If they do warn about possible effects, then increasing the temperature and/or time will increase the ...
Solar Mike's user avatar
  • 34.6k
2 votes

Safely washing engine bay of Ford Focus

I went ahead and cleaned the engine, and so far (after a couple of hours driving around today), everything seems OK. Before applying degreaser and washing, I disconnected the negative battery terminal ...
J. Taylor's user avatar
  • 433
1 vote

Hot bath for aluminium engine block and heads

I had a Porsche engine case halves and transmission case vapor degreased by a shop run by an ex-factory mechanic years ago. He used trichlorethane, which has been replaced by trichlorethylene, N-...
Stevie's user avatar
  • 11

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