Case sealant-how much is too much?
 

I was talking with someone the other day and he mentioned he toredown a case and found too much sealant was used, he could not see the mating surfaces. Since I'm a nOOb to rebuilds(only 2) How much should be used? Pics would be great(after application, before mating)

Thanks,
D

there are some great photos of just how much in the "book". I used an old toothbrush to spread out the bead and it looked just like it did in "The Book".

I ended up with a consistent, but light, bead of excess "squeezeout" around the external perimeter. Maybe equal in diameter to a pencil lead?

Hmmm I wonder who that someone could have been?

On an unrelated matter, here are some photos of a case I just tore down, finding too much sealant was used. I can't see the mating surfaces in many areas. One thing, I have no idea what glue the previous builder used. It is evident from the build that he is no Schmidt/Weiner/Walker etc. (more on that in another post). Anyway, the glue appeared to be some kind of non-hardening gasket dope or anaerobic adhesive, as it stayed sticky/gooey on the outside of the case for the 6-8 years the engine sat 'rebuilt' and unused before I got it. It was sorta magenta colored and not unlike Curil-T. Inside the case the excess squeezeout hardened into a brittle, hard crust. In many places it was so thick, the underlying magnesium mating surface is completely obscured. This engine was weeping oil from the case seam, one of many places. The pictures are kinda crappy, but I tried to sharpen them up:

http://forums.pelicanparts.com/uploa...1191383444.jpg


http://forums.pelicanparts.com/uploa...1191383517.jpg

This case is going out for stud inserts and oil bypass (and hopefully not first oversize bore or re-facing), but when it comes back I'm thinking I'm going to try Henry's 3-glue method. Any guidance on what sort of bead to lay down?

Actually, there are 4 sealants recommended. I layed a 3 or 4 mm bead of the Threebond 1104 around the perimeter of the LH case, then smoothed it out with an acid brush. I had a small foam roller that I used on the webs for the 574, just a thin orange opaque coat. The 12XX I spread out on the #8 saddle with my finger, and used Dow 55 on the o-rings via finger.

I like to use the 1104 on the half without the studs and then spread it with a plastic spatula.

DTW,

there is more than one builder around that still use "Formagasket" (that nice sticky brown crap) to seal up cases. Perhaps that is what the wizard who built your latest project used?

Cheers

Dave here is a thread on sealants, but no mention of bead size etc.

Hi Donnie,

Here is a great article that should help you out. (See page 47)

http://www.porscheownersclub.org/pdf/2002/winter.pdf

Regards,

That's a good article, thanks. I am surprised there isn't a $59.00 factory Porsche tool for this:D