scotch brite, the anti-christ

I've been doing a lot of searches here, getting accustomed to some of the details of the DRZ motors. I've owned my DRZ400K for almost 3 years now, but quite honestly, I haven't done a dang thing to it beyond changing the oil, and had no desire to do anything more to it, since I use it for tight technical woods riding, it was more than enough for my purpose.

Now that I'm getting more serious about increasing power (with the SM) I figured it was time to get edumicated :mad:

One thing I've noticed in many threads, is the dreaded words "scotch brite". I wanted to give a heads up to anyone that doesn't know, do NOT use scotch brite on internal engine components, or anything that will see engine oil. ANYTHING with aluminum oxide (which is the abrasive used in scotch brite, among many other abrasive products) is one of the quickest ways to destroy a motor.

Aluminum oxide is very nasty stuff. The particles can be/are very very tiny. So tiny, the oil filter won't stop them, ie roughly 3 microns. But they are extremely abrasive, and with enough quantity, can destroy a brand new engine in amazingly few miles. I myself destroyed a motor once, using "whizzy wheel's", motor had a rod knock within 50 miles.

Most of the different manufacturers have put out TSB's saying warranty is void for engine failures that they find traces of aluminum oxide.

Very nasty stuff. Hopefully, this helps someone.

Thanx for the tip UncleBob.

Thanks for the heads up.

ive been using scotch brite to clean engine case,cylinders and other parts for 20 years.there is no problem if the parts are final cleaned in hot water and detergent.

if you used it to clean the head surface of a car or something that the motor was still the frame i could see it being a problem.its very hard to thouroughly clean afterward.

bottom line,anti christ is a little over board.

the anti christ is poor cleaning procedure.

Sorry you had a problem, what is a whizzy wheel ? I used very small scotch brite pads and oil extensively to clean carbon off my head, piston, cylinder. I wrapped it around a popsicle stick and rubbed with oil to loosen the carbon. That was 2000 miles ago, no problems.

I always clean everything with hot water and dawn detergent using a toothbrush until it's sqeaky clean before assembly. I'm not trying to contradict your opinion, just present another view on the topic. If you can suggest a better method for cleaning carbon, it would be appreciated.

BTW, a peek at the 3M site shows silicon carbide and other abrasives are also used in the product, depends on what grade you use. There are also grades with no abrasives for cleaning painted aircraft.

While on the topic of keeping bad things out of the engine, a far worse (for me) problem was keeping dirt from under the tank area out of the valve area when re-assembling the motor. I used Saran wrap around the whole upper frame above the motor to prevent the dirt from dropping in when you brush the frame. It is almost impossible to not brush this area when jiggling all the cam chain tensioner components and cylinder.


As an aircraft mechanic I can say that scotch brite pads are an extremely effective tool for cleaning. If you have problems after using one, it's because you didn't clean your parts properly when you were done. If you were cleaning them while still in the engine then you need to let someone else do your motor work for you.

i could totally see it being a issue while doing a head swap on a car with the motor still in the frame.

yes you can clean out the aluminum oxide from the engine part. But if someone doesn't know the extreme importance of that (because no one posted such a thing) then they may not be as careful as they would be otherwise.

I look at it this way. If there are other means to clean off a surface, then why do it? Seems silly to use something so harmful if there's a chance of it doing damage to an engine.

But if you're going to use it, yes, clean up the parts thoroughly.

what is your recommended alternative? aluminum oxide rules out scotch-brite and most grinding wheels and most sandpaper.

depends on what the surface is.

All long flat surfaces that have no protrusions, such as head gasket mating surfaces, I use a wet stone. Not only will it get the surface nice and clean, it will also find and repair any low or high spots. You can do the same on engine cover surfaces, assuming again there are no protrusions.

That is by far the best way IMO.

Depending on the material, wire wheels work well too. Brass wheels are fairly gentle. This works well for carbon.

The main reality is, you don't have to get super anal. You don't have to remove every single spec of material off a cover. Many times, I will run a razor over the surface and just ignore those tiny little specs of gasket. They will not effect the sealing surface. If you feel it must be dealt with, use a small (pocket knife style) wet stone.

Better than sandpaper or steel wool for most tasks. Like any cleaning method or surface prep a good clean up afterwards is required, maybe even masking off an area before cleaning. to each t:thumbsup: heir own

I hope, at the least, those that read this, will be more cautious about cleaning up the surface they worked on. I would prefer to not see people blow up their motors. I think everyone agree's thats not fun.

I don't really understand some of the angst towards this post. Blown out of proportion? Maybe. It might seem different to you after you blow up an engine due to it though. Hind site has a way of bringing things into perspective.

No its not a sure thing, just because you use something with aluminum oxide. I was pretty confident I had flushed the above motor out well too. Turns out, hindsite disagreed with me. In hindsite, maybe I should have done things different. Hindsite is fun that always has the last word in matters, no matter how confident you have, or how "experienced" you felt you WERE.

this is not the first time I have read this type of warning, it's been on other boards also.

I would use caution with the wet stone also. They are abrasive also--hence the reason they sharpen things. Small particles come off the stone during use. I think that no matter what your poison is to clean things, care MUST be taken to thoroughly clean the parts of foreign material prior to reassembly. My theory is that parts can never be to clean-- anything abrasive is the enemy of moving parts!

sometimes you don't have that option, as eddie pointed out.

A wet stone is fairly hard though, it will win the hardness battle vs gasket surface, and definitely vs aluminum. Steel or cast iron, well, you'll be working it for a long long time before you make a dent into it.

Some materials are much more harmful than others. You can't SEE aluminum oxide. Which is why something looking clean isn't the end all

just to be clear any time i use scotch brite in conversation,its a hand held pad.not wizz wheels.

wizz wheels will remove material.they should not be used on aluminum gasket surface.

sharpening stones work as well but the particles are just as dengerous as aluminum oxide.

the parts must be cleaned thoroughly in detergent and hot water.

this just like honing a cylinder.i tell people to clean it 3 times and then 3 more times.

use a white paper towel and keep wiping the bore till the towel stopping picking up and "black".

as far as not having to have every speck of gasket off,you will never see a motor come out of my hands that every surface wasnt flawless and perfectly clean.

most wet-stones are made of abrasive materials too. I use a plastic scraper (autobody squeegee) and wd40 or paint thinner (xylene based) to remove gasket material. Good heads-up on the dangers of scotch brite though-it works so well it is tempting to use it without further thought.

as far as not having to have every speck of gasket off,you will never see a motor come out of my hands that every surface wasnt flawless and perfectly clean.

Thats why I am having Eddie do my engine this winter!:mad:

bead blasting of parts by somone who knows how will make any part look new and by thows who dont will turn it into garbage this goes for any use of abrasives are the parts youare trying to give new life worn out fitts and clerances can be taken up by dirt carbon etc putting clean parts back together dosnt make it new again it could just open up to ware due to out of limit fits and clearances

bead blasting is a no no in most cases.especially cylinder heads.its nearly impossible to get all the media out.

soda blasting is proper in this case.

as far the rest goes,worn out parts are worn out parts.clean or dirty.

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