PerryB

I'm finding this thin green sealant at the joint faces on my transaxle. I'm guessing that it's Curil-T. I've tried brake clean, acetone, paint stripper, gasoline and nothing dissolves it. I don't want to manually scrape it off for fear of damaging the sealing surfaces. Any suggestions?

T&T Racing

purchase honing stones 320 grit to 600grit

PerryB

Hmmmm, I don't want the grit in my transaxle. Also, any abrasive will mar the joint faces. Surely there's a chemical solution (pun intended).

mj951

Not sure if this is still available but Aircraft Remover would do the trick.
I've used it to remove the anodizing off brake calipers, works great.
You'll want to be cautious with it, gloves, goggles and well ventilated.

https://www.napaonline.com/en/p/MSRKSGAR343

T&T Racing

Purchasing high quality honing stones won't leave grit, grit is the terminology for how abrasive, the lower the number, the higher the abrasiveness. Just have the stone rest up to the lip. If concerned, just wipe the interior edge

Zirconocene

On the solvent side, methylene chloride (aircraft remover) will go after most anything. You can also try the red can brake cleaner with trichloroethylene. My memory is that product is not available everywhere (CA, for example), but there should be some available via Amazon, just be sure to read the label.

On the manual side, you can make a scraper out of copper pipe and be sure that it won't affect the soft (but not as soft as copper) metal. Just get a short length of pipe and hammer or squish it down, file an edge on it, and get to work.

Good luck

Tiger03447

If you use methlyene chloride as a stripper, be sure to wear CHEMICAL resistant gloves..It will eat right through nitrile and latex gloves.. If your fingers start to feel cold while using it, time to strip off the gloves and go wash your hands, VERY well If you let it stay on too long after that, it will start to attack and eat YOU...BTDT just sayin..

PerryB

Grit: --n. 1. fine, abrasive particles as those deposited as dust from the air or occurring as impurities in food.

Yes, thank you, I am aware of the number/abrasiveness scale. My concern was two-fold: I don't want to mar the joint surface (especially where Porsche doesn't use a gasket) with an abrasive or scraper and I want to prevent contamination of any debris from the abrasive inevitably entering the transaxle cases. What I asked for here is a chemical that will dissolve the old sealants, maintain the integrity of the joint faces and not sent grit into the interior of the transaxle.

Has anyone used methyl-ethyl-ketone (MEK) to remove this type of sealant?

Jay Wellwood

A bit snippy aren't you for coming into this forum, as a guest, seeking free advice from the members.

PerryB

Sorry if I am snippy. I felt that someone explaining to me how grit numbers are used to indicate abrasiveness was insulting

I've been a member of this forum for ~7 years and have asked for and offered advice when I thought it was appropriate. I have always tried to be cordial and helpful. I am sorry if in this instance I failed.

Back to the original problem...

Has anyone used Aircraft Paint Remover? Is methlyene chloride a common chemical stripper that I can get from my local hardware store? My googling of Curil-T only leads to description of its uses and places where I can buy it, not on how to remove it.

KevinGross

The green sealant could be Curil T or it could be Loctite 573 (or its equivalent). The way to remove sealant from these surfaces is a (fresh) single-edge razor blade - quick and easy. For bonus points, you can burnish any remaining sealant haze with a 000 synthetic scrubbing pad ("Scotch Brite"), which you can find in the furniture refinishing section of your local hardware store.

Chemical strippers aren't needed, don't work well, and are more hassle than anything else. Honing stones don't work either. Stay away from abrasives. If the sealing surface has been marred, yes, you can clean up the surface using a fine file (or honing stone).

The correct original sealant to use depends on the transmission. On the 944 series, a VW product similar to 574 (orange) was used between the aluminum differential carrier ("bell housing") and gear carrier (steel center section), and 573 was used on the differential cover plate after the o-ring was deleted in '84. (If you have the o-ring, no sealant needed.) On the 968 series, 573 (green) was used between the aluminum differential carrier and gear carrier because of the finer surface quality. It was also used on the three bolts securing the shift rod lid, because those bolts go through into the case. You don't need sealant where paper gaskets are installed. You can get both the 573 and 574 products in the US from Wurth.

Hope this helps,

Zirconocene

If you're committed to the solvent route, I don't think that MEK will do anything for you that acetone wouldn't. Acetone is methyl methyl ketone, so it's virtually identical to MEK. What about straight Simple Green, with no water? That's basically a long chain organic polymer that might give you some results that the simple, molecular solvents don't. I believe that there are also extra concentrated versions available.

For what it's worth, my go to inclination is always solvents (if that's not already clear) but there are some super good wrenches on here, Kevin among them, that you can trust to give you good guidance, even if it's not the path you first envisioned.

Good luck and cheers

16again2009

I've never used them, but I saw in a post where a guy used plastic razor blades to clean his gasket surfaces.

PerryB

Thank you for all the suggestions. I will follow Mr. Gross's recommendation to use a fresh single razor blade and lots of care, as I know that he has taken apart a zillion of these transaxles.

If I find a chemical that quickly and completely removes the sealant I will repost and let people know.

Alternately, if someone comes up with any further suggestions, please let me know.

T&T Racing

Kevin is the guru on transaxle rebuilds. Maybe you can PM him on the use of the activator, my familiarity is with 574. I found that the 574 cured better especially at the lower end of its working temperature range when first applying the activator before the 574.