How to clean engine?

[GAM2000]

Gunk is ok but try 3-in-one heavy duty cleaner degreaser alot better.

[harlemex]

cling film???  may as well wrap bits with tin foil or string perhaps.. 

[Khare]

I wouldn't like to try tin foil across the battery...

[Bellend]

I jetwash the battery directly. 

Then just apply a thin layer of terminal grease.

I just jetwash my engine with the engine off. Nice and cold as I don't like cold water being sprayed on hot electrics such as the coil.

TBH, I'm with Ess_Three, should be water tight and it always starts up after. Just don't directly spray things like the alternator or whatever. Have jetwashed my distributor and leads as they are all water tight, no issues. 

[forsh]

I did mine today...sprayed everything with Meguires de-greaser, brushed it in to lift the dirt, then foamed the whole engine bay with my foam lance and washed it off with my power washer.
I didn't cover anything with cling film...it's an engine...it sits gettig sprayed with water all year round...anything that needs to be water tight, should be water tight!

I've done the same for the last 23 years...and never had a problem.

The old ABF started first turn of the key afterwards too. 

this is what i did with my 1996 vr

engine de greaser all over,let it wait and soak in for 5-10 mins,then hot water and soap jet wash,nice and clean,nothing was covered up with bags or plastic etc

engine started first time

[polo6n222]

i know one of my old 8v would not like the engine getting to wet would not start

[danmusic24]

i just disconnected battery...sprayed with gunk all over left it ten mins rinsed off with hose left it to dry for couple of hours then reconnected battery and let it run for a while.no problems but would not use jet wash as have done this in the past and it blew my crank sensor wires to bits and blew ecu..