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No more engine stains......


Well-known member
Dec 6, 2000
Bradenton, FL
'90 ZR-1 #3010
The only aggravating thing about the LT-5 is the fact that it will develop stains over a period of time sooner or later. Earlier this year I purchased my '90 that has been very well taken care of with only 18,000 miles. Even in its low mileage condition, the LT-5 had developed little stains and various spots all over the motor.
I have heard a lot lately about extreme metal polish. I was very tempted to use this, but decided to try something different. I have used rubbing compound and followed it with standard polish and I think you'll be amazed at the difference. I won't get too detailed yet, as I've only done a portion of the motor, but the difference is astonishing. The sections that I have done do not even look like the same motor. I am literally pulling all of the oxidation, stains, and spotting right out of the intake and cam covers.
I have taken a bunch of before pictures and some pictures of the process as well. When I finish, I will post all the pics. It takes quite some time, but the results are unreal.......I'll keep you guys posted as I make further progress.

Are you attacking it by hand Jay? I mean, no power tools?

Yes, unfortunately, the LT5 engine paint will instantly stain if you give it a dirty look. It's not very durable. The two main causes of stains on the engine are coolant and oil. If you get coolant anywhere on a painted LT5 surface, you better make sure you wipe it off because if the engine is hot.....you can be sure it's going to stain.

Believe it or not.....in the past, I've waxed the engine just like I've waxed the body of my ZR. One coat of glaze, once coat of wax. I'm not saying it will work for everyone, but from my experience and 7 years of ownership experience and 23K miles, it's worked very well for me.
Just a follow up:

The motor is turning out really nice. Looks like a different LT-5 under my hood. I'm almost finished.......I've got half a cam cover to go then I'll polish it up and get some "after" pictures.

Have you guys thought about using a clear paint on the engine, like one from Eastwood? They make it to perserve the finish on aluminum, steel and diecast pieces . After spending all that time cleaning and polishing, there should be a way for you to seal it up. The stuff is called Diamond Clear and is advertised for up to 300 degrees. --Bullitt
i bought a car that had one of those "gloss" paint jobs on the motor. i'm sure it looked good when it was first applied, but when i got it at 65K it looked like **** - kind of greenish-yellow, you know, kind of a whitish snot looking crap. as you can tell, it was disgusting. i tried to get it off by spraying paint remover (after removing the plenum and injector housings, couldnt get the cam covers off cuz the "gloss" had frozen the bolts), but that took off the powder coat too, so i bought some lingenfelter paint and redid everything. it looked ok, but the engine is out of the car right now getting rebuilt so i've re-powder coated the appropriate pieces.

anyway, in my opinion, stay away from that gloss stuff ...
wow Rob, sounds like you had a real mess there for a while. I would love to see some pics of your motor after it's all reassembled. Someday I'm going to have the plenum and cam covers repowder coated, but for now $$ is the issue......I'm actually pretty happy the way mine is turning out :)


I just got finished snapping the "AFTER" shots a little while ago. The difference is amazing. Both "BEFORE" & "AFTER" shots were taken outdoors in as similiar lighting conditions as I could get. I'm going to try and get pics up tomorrow so you can see the difference......

fyi, Reggie W gave me a tip and told me that extreeme metal polish is stocked at lots of motorcycle shops. the bike guys live for chrome and this stuff works well on the LT5. I'm gonna investigate and let you guys know where I find it.

I may "stock it" for LT5 guys that want to come by and pick some up. my 95 looks pretty good but a bit more rubbing will make it better.

Yes, I have the Extreme, and it does work well. Really cleans. I bought a couple cases a while ago and offered them at cost plus postage, think it was $14 delivered.

If you want any, juse mail me with your check and mailing address, and it will go out same or next day. I can get as much as anyone wants. (See next post)

If you do mail me, be sure you mark "Extreme" somewhere on the outside, 'cause I am doing a tape deal for lots of folks who want the ZR1 owner's tape and LT5 training tape, about 3 hours total. I have a backlog there, so if you want the extreme, please mark it, so it won't wind up in the wrong pile of envelopes.


the tapes are $6, same method.

And the address which I left out also is:

Art Colley
711 Jefferson Highway
Baton Rouge, LA 70806

Again, Regards,

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