[MLB]

To get to this seal the intake manifold must be moved out of the way. I disconnected little bits at a time and was able to invert it, along with throttle body, upside down over the top of the engine (the cam cover had also been removed for other repairs, and I needed that clearance too). I didn't have to completely disconnect all this from every vacuum line, and I didn't disconnect coolant hoses from the throttle body.



So inspection of the rear seal of the upper balance shaft revealed a rattle-y loose seal (that would be a bad thing, right?), and a puddle of oil below it. Hmm, I think that just maybe oil has been leaking here recently...

So, I think I read that the entire cover for the balance shaft must be removed (maybe even the BS itself?) in order to replace this seal?

I am considering following the suggestion of MBardeen, who sealed the one on his car with some of the RTV730, which I already have a tube of (its horrendously expensive, but good stuff). Gotta clean everything scrupulously first though.



So whaddaya think? I've got access to the upper BS housing? Go all the way, or try the RTV first?



   

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[Lear35A]

unfortunately there is more disassembly than you probably want to hear about. The seal is just an o-ring that sits in a groove in the round piece on the end. it's that o-ring that gets worn and hard causing the leak. it probably cost a buck. however, to free the piece that holds that o-ring the housing cover must be lifted up a little or really it must come off*. the cover is held by 16 screws of 2 sizes. Getting those off is probably doable. however, on the front end is a piece that holds the front balance shaft bearing and the front seal. That housing is attached to the cover by a screws that would have to come out too. I've attached two pictures with and without the cover that might show this better than my words.

*the cover really should come completely off because it seals to the block with this loctite stuff. the machined surfaces of the block and cover should be dry and clean before you apply this. if it's not applied right, the cover will leak.

so i've probably talked you in to RTV, but that's the way it is.

almost forgot. you need to have pretty good access to the cover. you want a clean shot with a torque wrench to those 16 screws. mistorquing that cover is a bad idea.

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[MLB]

Thanks Lear, that's what I figured. and thanks for the great photos. What is that blue-ing on your balance shaft cover? has it been anodized!?

I'm going to put some RTV on the metal seal ring and just see if I think it's sealed well enough to reassemble the intake manifold.

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[Lear35A]

Either paint or powdercoat. I don't remember which. I think paint. I tried a lot of different things in my many engine builds to try to make it pretty.

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[MB968]

Did the RTV seal approach a couple of years ago (inspite of the fact that I had the engine out). I didn't want to take the bal. shaft off and work with resealing it, etc. Some purists might think I'm crazy for being so close and not just removing it. But, I've spent a carear around machinery and all the ins and outs. So, I was was quite confident that I could do the RTV successfully after looking at the design. And, to date, the fix has worked great. As with any seal application, cleanliness is paramount. I'm pretty sure I posted my comments on how I cleaned/resealed the rear with RTV on this forum. But, in short, the most important is to get surfaces around and under the rear plug clean. Use alcohol, or another high quality solvent. My plug was very loose; I could move it axially so there was a good gap behind it. I used q-tips dipped in the solvent to clean the rear side and outside diameter of the plug, and the surface behind the plug on the casting, and also on the diameter that is concentric to the OD of the plug that is on the casting. Filling this area completely after a thorough clean creates a seal well bonded on face and diameter, and thick enough to withstand the oil pressure that it will see in operation. I may not have tried this if not for the fact that many others have sealed this area from the outside successfully.



If someone else has already done the RTV seal to your car, and it isn't working, then I'd suggest the only way you will get a good seal is to remove the housing shown in the pic above, as I doubt you'd be able to clean off the old RTV well enough.

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