What the bloody hell is it

G'day Roughneck,
I assume you're asking specifically about cleaning the engine/ engine bay???

Depends how "dirty" the engine is to begin with....

If it's got a few oil leaks & has a bit of a build-up of crud around the place, then a degreaser (yep, that's what it's called, "degreaser") is the go.. best applied to a warm engine (watch that exhaust manifold!) and left to "work" for a while before hosing off with moderate-to-high water pressure....

If it's not too grotty, then something like (Chemtech) CT18 Superwash will do the job nicely.. This is a foaming detergent that you spray on (diluted) & hose off.. It too is more effective if left awhile before hosing off...
Good idea to cover any electrical stuff (alternator etc.) when you're sprayin' water around in there...

Any half-decent auto accessory shop should have something that'll do the job...
Hope this helps..

Regards,
Ed. C.

Hi roughneck, did a fair bit of the detailing in my younger years,we always make sure the engine is cooled off a bit first before cleaning it,then we'd give it a coat of either degreaser or kero first,but only IF the motor is very oily.
Then we spray on a chemical called Alkasteam or there's one called Trucksteam ,and these are diluted to 50/50 as they can damage paint work if they arent diluted.Then it's just a matter of giving it 5 minutes to soak in and then hit it with a small jetwasher or hose.The Alkasteam works particularly good on and around the fire wall section of the engine bay to remove all the built up bulldust and mud etc.Just remember to the that motor cool off first though,dont want any craked manifolds or heads from tyhe cold water though! These chemicals are available through Autosmart or Opal cleaning products.Or visit ya local detailer and usually they sell you some we used to just spray it on with a hand squeezer type spray bottle(same as the barber uses),cheers.