Power Washing the Engine Compartment

[Guns314]

Hello All,
My First Post -
I've got a power washer that can provides from zero to 250 degrees (steam) at 3600 psi.
I want to clean the engine compartment but am hesitant. I don't want to damage anything.
Should the engine be running? What should I avoid? Does anything need to be covered? What to do and what not to do? Any feedback?
Thanks everyone.

 

[Fixitorelse]

Make sure you don't spray any seals/gaskets directly at a close distance.

 

[1998Exp]

For what it's worth, just about every single engine compartment that I have seen after steam-cleaning had the electrical tape wrapped around wire harnesses stiffen and crumble. It doesn't hurt anything, but sure is annoying...

 

[Joe Dirt]

No to gaskets, electrical connectors...

You can get good results with everything from Simple Green and a rag, to can engine cleaner and light hose pressure, to medium pressure, to some guys pressure wash all the time.

As you progress through that sentence, the potential for problems to creep up and give you issues tat you will be chasing for a long time increases. Use with extreme caution. If it was me, teh most I would do would be a couple of cans of engine degreaser, a misty hose, and an air compressor. Then start it up to evaporate. Do not wash it when hot.

 

[OneLever]

Welcome to the forum!

My personal opinion is that you shouldn't use a pressure washer on a car's engine bay. At least not on a decade plus old vehicle with brittle wires and connectors. I would stick to low pressure or mist rinses and a degreaser. I would have suggested Simple Green but there were some reports of it causing corrosion in the past. If you really want to look into it I'd find a degreaser which is approved for use with aluminum in the aviation industry since they're a bit more stringent when it comes to corrosion.

 

[fbc]

See if you can dial you machine down to maybe 1200 psi to make sure nothing is damaged.

Anything brittle or falling off with that, you might want to change anyways as it was about to break and leave you stranded any moment now.

I would warm it up, spray it down with a bottle of simple green, wait about 5-10 minutes for the simple green to act, then spray away.

 

[2TimingTom]

I've washed my engine at the coin-op car wash. But I usually don't pull the trigger. And usually at that point, my engine is warm/hot because I've just driven to the car wash.

As those engine degreasers, good stuff, but if the run off gets in your lawn.....

 

[zembonez]

I've used the local high pressure car wash on mine (always hot and running) countless times. I'm currently at 213,000 miles and never had a problem. Use a little common sense when spraying electrical components and you'll be fine.

Using a high pressure steam cleaner might pose a bigger problem. I'd use a car wash.

 

[Paraphoe]

I've done it with low/medium pressure. Had a ton of mud and sand to get rid of. Covered up sensitive electrical components and took care not to blast any connections or anything too close or hard.

 

[Joe Dirt]

Seriously guys- if you're using cold water, spraying it on a hot engine is not a good idea...

 

[fbc]

Seriously guys- if you're using cold water, spraying it on a hot engine is not a good idea...

Yeah, i don't think spraying cold water on a hot engine is being suggested by anyone.

I just idle mine in the driveway to warm it to help the degreaser out a bit. The degreaser stays on for about 5-15 minutes anyways, giving the engine a chance to cool down (even if it was hot); before I spray it.

The use of common sense it good too.

 

[Joe Dirt]

I've used the local high pressure car wash on mine (always hot and running) countless times. I'm currently at 213,000 miles and never had a problem.

Just depends on how you read it... bonez is right though- common sense goes a long way on this stuff...

 

[fbc]

bonez is right though-

Who's bonez? Beam me up scotty.

 

[Joe Dirt]

zembonez- the member I quoted from...

 

[Hartman]

I powerwash mine and leave it running while I do. Never had any problems.