Hi, I have a 1993 Honda Accord with 46,000 miles on the clock. The car is in good clean all round condition. The engine bay is filthy. I was about to thoroughly clean the area when a neighbour (who works in a garage) mentioned that cleaning was not a good idea on older vehicles as water could ingress into the electrical system. I like the idea of a clean engine bay, but do not want to start up future problems. What's your opinion?? Thanks - Paul, London UK.

 

This is kind of a debate. I would suggest that you cover some items like the distributor. Be careful of spraying water directly in/onto the alt.

I've used engine cleaning products before on my older ones. Follow the directions and you should be fine.

 

I agree w/ PM on this.

I've used Simple Green to loosen material and pressure washer while avoiding distributor. Warm engine slighlty (not fully warm, 2-3 mins idle) to help loosen deposits. Allow to air dry and the restart and fully warm. Never had any problems.

good luck

 

Wow, I never thought that water should ever be allowed under the hood until reading this thread. My 2005 Accord seems to have way to many electrical wires under the hood to allow me to feel comfortable spraying water on everything in there.

But, since there are people who have done it to, i guess it is no big deal. Youtube has many videos on engine cleaning as well. There are new cars as well as old cars in the videos, so apparently it's still safe even for later models. Looks like it's going to be a satisfying job. Have fun!

 

I do mine ever 6 months or so. I power wash with engine running and just be mindful around electrical components. My 96 went to 430 k.

 

Thanks for replies guys, I guess using sensible precautions and protecting 'the vitals' it should be ok. And warm her up afterwards. I have a water soluble degreaser called 'GUNK' that I used to use on my motorcyles back in the early '70s, will have a go with that. Kinda looking forward to it too..

 

Most of the "important" wires are weather sealed, so spraying the engine shouldn't be an issue. Just avoid using too much pressure with a pressure washer and also avoid spraying into the alternator and distributor. I say not too much pressure becasue if you have too high of pressure it could push past the seals, or even cut thru things. Keep the end of the wand at least a foot away from anything.

 

If you decide to do this, keep a few things in mind...

Use a safe degreaser meant for use under the hood...Gunk Foamy Engine Brite Degreaser Spray has very good cling properties and gives excellent results.

Do not use it on the cars finish paint under the hood, engine bay etc. It will dull the finish if left on for a bit.

Avoid plastics, ignition wires, distributor, all hoses and other rubber components.

Let the degreaser do the work and use the pressure washer with caution especially around electrical...fusebox, relays, solenoids, and ignition components. Keep the tip at least a few feet away from these areas. Stubborn or extra greasy may need a second treatment, or use a toothbrush to remove the crud.

Be prepared to troubleshoot a wet ignition, or you can cover it up with rags and a heavy duty ziplock bag/duct taped shut.

 

Also watch for vented reservoirs.

Brake fluid reservoir has a tiny vent built into the cap.
Clutch fluid reservoir too.
Battery caps are vented.
P/S fluid reservoir is not really sealed, so you can get water in there if you're not careful.

Don't be too paranoid about it; just take a look under the hood after driving through a good rain. Plenty of water sprays up there from the road.

 

I used to do it all the time with my 92 Accord. I would wash the outside first, to let the engine cool down, then spray everywhere under the hood. The wiring on these cars is pretty good and sealed, I just wouldn't spray the alternator or distributor too much, but never covered anything. I wouldn't try that on my chevy truck, cause the wiring looks shoddy, but I never had a problem with the accord. I do it to the 03 Accord too.