hey guys i struggled with ballance shaft seals leaking all last season i bought new seals to install them tomorow but my problem is that i already replaced them last season so im guessing im doing something wrong or theres a trick any help would be great oh jus to clarify i only have leaks from the back seal thanks John

It's just a funky design. A healthy application of your favorite high temp gasket sealer is your friend.

Ok so rtv around seal what about the mating surface of the cover

I've always used the factory method, the high dollar orange Locktite 574, and never had a problem with leaks. There are some folks who use other products like from Dow-Corning. A search on Rennlist or PelicanParts forums should show you. I've only used 574 so YMMV.

Likewise. FWIW, spent a LOT of time with Loctite Tech Data Sheets trying to see what was the difference for example between the expensive and not on the shelf 574 versus the cheaper and more common 518 and others. Not at all clear one is actually (much) better than the other; and I wonder if part of the oem recommendation has to do with what Henkel (owns Loctite) had in 1980 vs now. You could do worse than spend an afternoon with the information on the Loctite site.

Just now I found this application site and it's the first time I've seen that 574 get's recommended for a 'semi-rigid' joint: http://useloctite.com/index.php

Permatex was owned by Loctite/Henkel for a couple decades. So the similarity of products may be more than superficial?! In any case Permatex is often on more shelves and they show several flange sealants that should be quite as good.

As an experiment I did use 518 on the upper balance shaft surface of the last motor I did. So far as I know that motor did not leak (there any way - ask Matt). Next time doing one for myself I intend to use just 518 everywhere. When I run out of 518 I'll try the Permatex.

Just remember that for the seals, there are two sizes, one for the top and one for the bottom.

thanks guys i pulled the top housing off yesterday and hopefully bottom tonight. i had no idea about the diffrent size orings for the rear caps ill have to look into that i dont remember when i ordered the orings. also i discovered that the rtv i used to seal them the last time was blue and it was verry easy to remove i used a copper permetex rtv to make a patch over the rear caps and it was sealed up tight so i think thats the rtv ill use for the whole thing and to be safe ill cover the rear caps again

Just to be clear we've been discussing 2 very different sealants: anaerobic (574 and 518 etc) for the rigid casting face(s) and rtv to aid the o-rings.

With the motor apart and the surfaces clean only a small amount (if any) rtv is needed to help the o-rings. More is either wasted or something is wrong (or dirty). Notably the castings must be installed straight. Contrary to what some expect if you want to assemble the o-rings without rtv try putting a tiny bit of oil or grease on first. Lets them move with the castings and not get pinched or distorted. There is little or no pressure behind the o-rings; they are not a pressure seal. Only crankcase pressure.

im going to look into the diffrent sealants thanks for clarifying that for me

I figured you were writing about the front shaft seals leaking rather than the o-rings that seal the ring on the rear of the case. The rear o-rings are both the same size, but different part numbers for the early and late engines. The shaft seals on the front are 30x47 on the top and 30x48 on the bottom, regardless of year.

FWIW, I've used both Loctite 574 and Threebond 1194 for the case halves and have never seen a case leak in four engines.

Steve