Removing anerobic sealant

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Removing anerobic sealant

Postby BillW » Tue Jan 16, 2018 7:33 pm

So there is always lots of chat about how to apply anaerobic sealant. Not so much on how to remove the cured, thin film that it leaves. I know lacquer thinner doesn't do it. It seems to me that acetone used to work for me but it's been awhile and I was never quite sure, as that stuff is difficult to see. What do you frequent rebuilders use to be sure it's all removed?

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Re: Removing anerobic sealant

Postby Mumbles » Tue Jan 16, 2018 11:14 pm

Careful scraping, sanding, and soaking with lacquer thinner is what I used to do until I found these 3M discs at my auto supply. They are used for gasket removal to and come in different colors or grits and the parts guy said to use the white ones on aluminum. They aren't too aggressive but must be used with a light touch. ... 502&rt=rud
3M Bristle Disc.jpg
3M Bristle Disc.jpg (17.13 KiB) Viewed 747 times
Still searching for a rudder and hardware to fit a KOBAN. ☺

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Re: Removing anerobic sealant

Postby zul8tr » Wed Jan 17, 2018 5:10 am

Do not know what brand anaerobic you have to remove but Permatex makes a remover for their anaerobic products. ... c-formula/

I have heard where paint remover works well to remove the anaerobic, never tried it.

If removing the anaerobic from split crankcase design engines (ex Merc Mark 30, Mark 55, Merc 200, etc) that have accurate machined mating surfaces then they are put together (without sealant) and line bored for the crankshaft/ reed cages/bearings/etc to very close tolerance as a matched set you need to be careful to not damage those 2 mating sealing surfaces. Also if resealing these split case engines the mating surfaces need to fit nearly perfect then it only takes a very very thin layer of the anaerobic to do the job. I always check the flatness of the split crankcase mating surfaces and correct any highs before sealing with a very thin dappled coat of anaerobic. My applications of anaerobic on split crankcase engines are so thin that to remove sealant is not an issue with a careful draw scrape with a razor blade.
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Re: Removing anerobic sealant

Postby BillW » Wed Jan 17, 2018 5:59 am

Thanks for the replies so far. I will consider both, although I have come to expect little help from any product that says, "Low VOC." Overnight, it occurred to me that our detailers have some plastic "razor blades." They look like razor blades and fit into the same tools/holders but are plastic. I am going to try score some of them, along with some acetone. (Yeah, I I know I can't use both at the same time because the acetone will eat the plastic.) I am currently working on a lowly 3.3 Tohatsu-based "Mercury;" but I am looking to improve my general technique in removing that stuff. I intend to add the motor to my collection when done, as a monument to horrible pieces of crap. I think they used the worst salt water aluminum of any motor ever built. Even some of the crank case screws were beginning to corrode in place. I don't even know how that is possible.

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Re: Removing anerobic sealant

Postby Chris_P » Wed Jan 17, 2018 7:13 am

Im with Mumbles. I use a dremmel tool now. Then clean with acetone.

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Re: Removing anerobic sealant

Postby Jeff Register » Wed Jan 17, 2018 6:25 pm

10-4 Chris. Be careful though, had the Cops over thinking we had a meth lab between glassing & prepping, Close to infred heat signature,
Now all those neighbors are gone....You know never paid taxes ; > ) !! Not to bring up neon fall-out 2. Many are nuts!

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Re: Removing anerobic sealant

Postby jw in dixie » Thu Jan 18, 2018 10:01 am

If it's that black irremovable stuff, I got some off of my TBird trunk under an ugly antenna with Goof Off and a lot of rags and elbow grease.
A slow process but it came off clean. Had tried all of the solvents mentioned above with no luck. Also tried Goo Gone. Good luck.
JW in Dixie

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Re: Removing anerobic sealant

Postby Jerry Ahrens » Fri Jan 19, 2018 7:31 am

I've always used Berryman B12 carburetor cleaner with a razor blade... I always drag the razor blade backwards though,
to not nick up the mating surfaces.
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Re: Removing anerobic sealant

Postby fleetwin » Mon Jan 22, 2018 6:05 pm

This is an important step for sure, and a difficult one for sure. That thin film of sealer left behind is impossible to see but definitely enough to shim the crankcase halves apart and create leaks...
The OMC gel seal remover is potent stuff but does the job. OMC even recommended using a black light to check the halves to ensure all the old gel seal film had been removed....

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Re: Removing anerobic sealant

Postby BillW » Tue Jan 23, 2018 5:54 am

Now we're talkin'. I don't ever remember either of those two ideas. I guess I was sleeping at the seminars or skimming the manuals too fast! I am going to look into both of them. Thanks!!

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