Power washing undercarriage- what to look for - ZR-1 Net Registry Forums

billschroeder5842 · 07-23-2024

I have a power washer (1600 PSI) and I'm thinking of washing the undercarriage and wheel wells on my '91 ZR1. I'm also thinking of doing some engine/cradle washing but only below the heads-- nothing on top that can get through the plenum.

I'm just looking for a general clean up of the suspension and undercariage- I'm aware to stay clean of electrical connections.

Is there any concern about a general clean up? Is there any areas or components that are particularly fragile?

I posted this also on CF so we see what they say.

Thanks!

WARP TEN · 07-24-2024

I would definitely suggest using a very low pressure on your pressure washer. A number of years ago I had a friend who got a pressure washer to clean his boat decks. When he first tried it it was set at 3,000 psi and he promptly blew a hole right through the fiberglass foredeck. But more practically, you might want to spray degreaser on the greasier spots first to loosen things up. Also, while more expensive and normally done by professionals, you might consider dry ice blasting. That seems to work really well without the mess of a lot of water in your driveway or garage. But it is a bit pricey. Good luck!--Bob

silver86 · 07-24-2024

I would 2nd the dry ice blasting. It is pricey, but does not blast away anything that shouldn't be.

billschroeder5842 · 08-29-2024

Quote:

Originally Posted by silver86

I would 2nd the dry ice blasting. It is pricey, but does not blast away anything that shouldn't be.

I'm interested, but don't really have an idea of how it works. I always heard that one must stay away from the top of the engine (plennum area) as liquids under the plennum can really mess things up.

conesare2seconds · 09-02-2024

I?d avoid using the pressure washer altogether. If you do, give special care to wiring looms. The plastic is brittle from age by now. If you do the wheel wells you will encounter the wiring for the ABS/wheel speed sensor. I?ve seen that wiring losing its insulation, flaking off, probably contributed to by brake heat.

AirbusDriver · 2 Weeks Ago

I've heard, but no idea if it's valid, dry ice can/will remove factory applied undercoating...if that's important. NCRS types would be concerned, for sure.

07-23-2024	#1
billschroeder5842 Join Date: Nov 2016 Location: Southlake, TX Posts: 591	Power washing undercarriage- what to look for I have a power washer (1600 PSI) and I'm thinking of washing the undercarriage and wheel wells on my '91 ZR1. I'm also thinking of doing some engine/cradle washing but only below the heads-- nothing on top that can get through the plenum. I'm just looking for a general clean up of the suspension and undercariage- I'm aware to stay clean of electrical connections. Is there any concern about a general clean up? Is there any areas or components that are particularly fragile? I posted this also on CF so we see what they say. Thanks! __________________ Bill Schroeder Texas Proud! 1991 Corvette ZR1 #1388 2015 Challenger Scat Pack Shaker

07-24-2024	#2
WARP TEN Join Date: Apr 2007 Location: Lake Bluff, IL Posts: 2,082	Re: Power washing undercarriage- what to look for I would definitely suggest using a very low pressure on your pressure washer. A number of years ago I had a friend who got a pressure washer to clean his boat decks. When he first tried it it was set at 3,000 psi and he promptly blew a hole right through the fiberglass foredeck. But more practically, you might want to spray degreaser on the greasier spots first to loosen things up. Also, while more expensive and normally done by professionals, you might consider dry ice blasting. That seems to work really well without the mess of a lot of water in your driveway or garage. But it is a bit pricey. Good luck!--Bob __________________ 2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough"

07-24-2024	#3
silver86 Join Date: Sep 2023 Location: Canton, GA Posts: 17	Re: Power washing undercarriage- what to look for I would 2nd the dry ice blasting. It is pricey, but does not blast away anything that shouldn't be.

09-02-2024	#5
conesare2seconds Join Date: Jul 2016 Location: Greater St. Louis Posts: 488	Re: Power washing undercarriage- what to look for I?d avoid using the pressure washer altogether. If you do, give special care to wiring looms. The plastic is brittle from age by now. If you do the wheel wells you will encounter the wiring for the ABS/wheel speed sensor. I?ve seen that wiring losing its insulation, flaking off, probably contributed to by brake heat.

2 Weeks Ago	#6
AirbusDriver Join Date: Jul 2016 Location: Harrodsburg, KY Posts: 434	Re: Power washing undercarriage- what to look for I've heard, but no idea if it's valid, dry ice can/will remove factory applied undercoating...if that's important. NCRS types would be concerned, for sure.