I'm about to pressure wash the engine bay of my '91 Trans Am Convertible (5.0 L, TPI, 5 SPD, unmodified, 1 owner). What areas should I mask off to prevent water intrusion?

 

Not an expert but I don't think I would pressure wash it. Maybe spray with cleaner and gently hose off.

 

There's no reason water should get into the interior by power-washing the engine compartment...

 

Just cleaning the engine bay; not the interior. I'm thinking coil, dist cap, air intake and MAF, etc. but thank you for your comment. I should have been more specific.

 

'Sorry, I was thinking with the engine out like when I did mine.
Cover all the stuff you mentioned.
Most everything else should be fine...

 

I wouldn't PRESSURE wash...that'd just force water into crevices, wires and corners it shouldn't get in.


I just spray everything down with simple green, cover the alt, and shoot down with a moderate pressure garden hose nozzle. Less pressure / avoid electrical connection's.For stuck on grease, simple green and a moit terry towel to break up the grease then shoot down again.......I should but don;t cover the dizzy lol


Works EXCELLENT.

 

Thanks for the advise, 1989karr. After 30 years I figured it was due to be freshened to knock down the typical dust and dirt. The suggestion to use Simple Green was a helpful reminder. I was going to try Spray 9.

 

No prob!

if you got compressed air use that to knock anything dry loose...youd be surprised what flys up / out.



give the simple green about 15 minutes to soak in.

i've also used 409 but my fav is simple green.

 

I like SuperClean...

 

I've found simple green to be the best balance of cleaning power, while still being gentle enough to not damage any of the finish underhood, if that's important to you. ...and I've always let it soak, then use various brushes to dislodge and clean. For the first time in many years, might have to do it more than once!

 

This is good advice. This is what I do, then dry vac everything before wetting anything.

 

I have never hosed down an engine bay of any car I've ever owned. Too much risk of water entry into connectors, past seals, whatever. Wipe it with a towel if you want to touch things up.

I've seen a lot of sealing tests of electrical components in my years. It's very difficult to seal things and it's one of the biggest issues with electrical hardware. Pressure wash is intuitive, people understand why that's difficult. But you would be surprised how difficult it is to pass high-volume low-pressure water sealing tests.

 

Been blasting my 89 formula 350s engine compartment a few times a year since 1991. I don't cover anything, just use commonsense about how and where I spray full power. Hot water and a soapy mitt with a few drops of dawn go a long way. With normal cleaning, mine isn't greasy or oily so that isn't really a thing for me to worry about.

 

I agree, it really makes a difference appearance wise AND makes things easier to get to / inspect when you change components....just need common sense.

 

I’ve power washed my engine and bunch of times.. as stated, use common sense. Stay away from dizzy and alt. Also, after I power wash and clean, I close the hood, let the car idle for a little bit then go for a ride to ensure the heat if the engine dries everything out under the hood. Never had an issue

 

I wipe by hand, and touch up with compressed air. power wash will destroy decals, stickers and other things that are cool historical records.

 

Typical organic dirt like dust, pollen, and road grime, go with the Simple Green. Greasy oily mess anywhere, go with the Superclean or ZEP degreaser. Spray liberally on everything, allow it to sit 5 minutes, and rinse with a hose and spray nozzle. No need for a powerwasher. Repeat and even work real bad areas with a paintbrush. Repeat until clean. Fire it up and go for a 15 minute drive. Come back and park with the hood open until everything cools. IF...it's all clean you would now use a dressing to make everything look new again. Use some aluminum foil to cover up the drive belts first. Here is the engine of my daily driver/tow rig '04 Xterra........hasn't been detailed in roughly 12,000 miles. Makes a BIG difference when you need to work on something too, you're not digging through muck. When I had this thing aligned a while back the guy at the shop said he couldn't believe how clean this old Nissan was!

 

Thank you for all of the suggestions. I will probably leave the pressure washer in the corner of my garage and just do a Simple Green spray down and rinse with a mild hosing. The car has 165K miles on it but it has been well taken care of by me (original owner). I appreciate having a site I can go to to ask questions about 3rd Gen things I have not dealt with - this will be a good 30th birthday present for the car!