Engine bay washing

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Is it safe to do on modern cars with all the electronic gizmos?

I've just watched Edd China on Wheeler Dealers spray detergent all over a 20 year old Merc G Wagon's engine bay, then steam it off - with battery disconnected of course!

I would imagine its a job for the summer months and would need a few days dry off time?
 
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There is a hell of a difference between a 20 year old Merc engine and a modern overly electronically controlled engine. If you decide to do it make sure you cover all the electronics especially the ECU. Personally I wouldn't bother on a modern car, too much to go wrong.
 
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So how does washing by hand stop water getting where it shouldn't?
 
Considering the volume of plastic covers and the fact that oil leaks aren't anywhere near as common a few years ago, I just give the engine bay a good blast with compressed air.
John :)
 
I've been washing engines for more than 20 years. If there has been an oil leak you have to clean it off first. For general road dirt and especially salt spray which is very corrosive, a soft brush and a bucket of warm water and car shampoo will do. For very grimy areas, scrub with a small paintbrush and neat shampoo. Rinse off with water. I use a garden hose. Not a high-pressure sprayer which is more likely to get into things. Remember your car is built to withstand you driving up a motorway in a thunderstorm in traffic spray.

In the old days, you could get water in a distributor cap and have to open it to dry out, and air filters were not so well designed to drain away water, so you had to cover them or stuff the inlet. Remember you may also have a pollen filter under the bonnet. Clean out the drain holes befire washing. They fill up with leaf debris.

You can wipe away the water with a rag. Leave the bonnet up, preferably in sun, to dry. When it is thoroughly dry, you may like to spray electrical or rubber parts with WD40 if you like the smell. Armorall restores shine to faded plastic.
 
It's a pretty common service offered by car valeters so can't be that risky, plenty of guides on YouTube .
 
I suspect the water damage to the electrics manifests itself long after the engine has been washed so they'd deny all knowledge. You could always use brake cleaner to clean up any localised leaks.
 
Do you still have the cars with the engines you washed 20 years ago ?
 
Do you really think it takes 20 years to show?

If so, not many people would worry about if.

Longest I have kept a car was 12 years. Washed the engine multiple times, and rinsed off with garden hose. Saw it running around locally for a few years afterwards. Buyer pleased with it. I still do it. Washed two about 2 weeks ago. Running fine.


(photo removed due to stalker)
 
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Good luck. As I said leave it well alone or get a valeter to do it then it's his responsibilty when the ECU goes tits up. Perhaps the clever people on here who say they have been doing it since prehistory would like take the responsibilty.
 
yes, I'm perfectly happy to take responsibility for the cars whose engines I wash.

Have you got a car that can't go out in the rain?
 
No way will I pressure wash my engine bay.....although I love the green colour of the verdigris on the multi connectors :mrgreen:
A bit of water splash is fine....a concentrated deluge is another.
John :)
 
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