Cleaning up engine And tranny LS do's and donts

[ibbowhunting]

Can I safely pressure wash My donor engine and tranny 6.0 LQ4 & 4l80E
if I cap off the intake, exhaust gas lines, tranny output and tran cooling lines, the wiring harness is removed, also can I pressure wash the wiring harness separate from from the engine, or I'm I asking for trouble

[ls1nova71]

Make sure the engine is sealed up good and wash away, it'll be fine. The worst part about LS engines and washing them is the knock sensor plugs get hard and brittle and no longer seal so water can get in where the knock sensors sit and will rust them up, but you can silicone them to prevent it from happening. But if you're doing it out of the truck before you install it, it shouldn't be a problem. Same goes for the harness, water itself wont hurt it at all, its when water gets in a connector and is allowed to sit in there without drying out that it will cause a problem. All that said, I regularly wash all my engines.

[davepl]

Just make sure there are no Corvette C4s on the block when you do it. Spraying any water even NEAR an optispark will destroy it.

LS motors are pretty well sealed up, but I'd still stay away from and cover the coil packs!

[Willie Makeit]

I've never had any issues washing the LS-style coils. spray em down with purple power, brush, rinse and then used compressed air to dry them off. <shrug>