The only things that could be leaking from that area are:

- Through-bolt holes
- Cylinder base gasket

It's a 930 case, so it's unlikely that the cylinder spigots are off. Also, the cylinders are not known to leak heavily. I would suspect the through-bolt holes. Did you use black silicone on them (as I recommend?).

Note:the black silicone in this case is on the outside, and is external to the engine, with very little possibility of making it inside. I prefer to use a bit of Curil-T on gaskets that I think may leak in the future.

-Wayne

Maybe someone can explain how theres a difference between silicone, non hardening or hardening permatek, or curil T. Any of these can clog a squirter if it gets in the wrong place. Any of these can break off in a gob. The reason they do not become a problem is that the people who use them are carefull. Some are not and so the bad rap.

Make that 4
 

Please tell me WHAT is "reasonable" about concluding that 911 motors are POS (for oil leaks) from a study of ONE (which you admitedly rebuilt. . .that leaked)

The reason people are "attacking" you, is because they don't look forward to the task of re-educating those whom have read, and picked up some "jackism" from one of your half-baked posts.

When a newbie comes to Pelican, seeking info about a 911 rebuild, they certainly do not want to wade thru a bunch of missleading posts.

The thing is, Snow, You come across with a confident maner, touting vast experience. Though, what you're not posting (enough about) is your lack of 911 engine rebuild experience.

Hey, an idea; go work for Motor-Mister (you know; "well known, high volume, 911 motor rebuilder") . . .I think that with their special set-up; you could apply some of your special processes, an have a real meeting of the minds.
:cool: just think of the damage you could do here, with all that 911 experience.http://www.pelicanparts.com/support/smileys/eek3.gif

this post made possible by a contribution from the Special Olympics Organization.

I think that Jack has a wealth of useful information and can be a positive contributor to this board. However, I also feel that his experience in the Chevy world is a handicap - somethings are just different here. You goop up a Chevy motor with silicone - standard practice. The 911 (and VW) engines have no gaskets on the case parting lines - they are higher precision engines.

Jack, I think you speak a bit too emphatically, stating what is your opinion, but making it sounds like facts that are carved into stone. Back off on your rhetoric, and you will fit in a bit better.

-Wayne

Well on the subject of Porsche engines and oil leaks. Indeed the first 911 ( I have rebuilt 356 engines for over 30 years) had a oil leaks, a lot of them and I tore it completely down over 3 times trying various ways to fix them, finally resorting to the old standby of goo, lots of goo. I also talked to probably over 30 people, some of which have rebuild 100's of 911 engines in the process of trying to find the source of the leaks. That helped jar my memory of looking at 911s back in the 70's which did indeed have oil leaks on the showroom floor. Porsches are NOT a POS. The leaks are really only drips, one to 5 or 6 drips a day, never ending drips, that cannot be stopped if you use original Porsche stuff.

I consider myself a good enough mechanic, that if I tear an engine down 3 times just to get the oil leaks fixed, before its ever put in a car, and cannot find a difinitive reason for the leaks, except that they all seem to do it, and people who have 100's of man years experience cannot solve the problem without silicone or something like it and I have put months of effort into finding the bottom line on the subject, I do kind of get authoritive. Sorry about that.

Actually, we have something in common. Leaks drive me crazy too, and I am about to install my rebuilt SC motor that has been sealed up using more or less the latest info on leak-proofing. It is my first 911 motor rebuild, (I've done other makes w/ good results and no leaks), but I have had some very expert help and advice+ read every book out there including Wayne's.

The reason that I say, "more or less the latest info", is that even the respected experts have individual opinions on certain procedures and chemicals/sealers.

I do believe that 911 motors do not have to leak, though. I worked at the dealer in the '80s and they definitely did not leak on the showroom floor. Not saying that this never occured, anything is possible, but w/ Porsche's obsessive quality control and testing of each car, (at least in the air-cooled days), ;) , it's a little far-fetched.

Air-cooled engines expand and contract a lot more than cast iron liquid-cooled machines, the engineering challenges and mechanical knowledge required are quite different. These motors are almost like a living, organic thing, kind of like "Furbies", if you will. We have quite a few people w/ light aircraft knowledge and experience around here, they are particularly valuable on a 911 board. Try not to get too frustrated w/ these machines, they are incredibly rewarding once mastered. Take care. :cool:

I remember this very clearly now. It was 1969 and I bought a new car that year. I looked at quite a few differen't ones. I remember the Porsche because the salesman stated that they did not keep them on the showroom floor because they leaked! They were all lined up outside, except one. They had several 911's and 912's. It was in Rochester NY or Elmira NY, I don't remember which. I did not end up buying the Porsche.

What a load of rubbish!

So I guess Max Hoffman had to hire extra staff just to clean under all the Porsches in his (indoor) Manhattan showroom??

Let's see, where were we? Oh yes, the engine leak...:rolleyes:
I removed the air baffles to inspect the top thru-bolts on cylinders 2 & 3...dry. Removed head studs to pull cylinders out sufficiently to inspect lower thru-bolt nuts...damp. Removed thru-bolt nuts to inspect sealing rings...dry. Inspected #2 cylinder spigot gasket...kinked!!! It appears that #2 gasket had shifted during assembly. That is, rotated enough that when the cylinder was pressed down, the scallops were no longer aligned with the head studs, causing the gasket to rise around the areas of the stud. This prevented the cylinder from completely sealing the spigot bore. Can't explain it... the left bank was up during assembly to minimize this type of event from happening. Maybe the spigot bore was oil damp which prevented the adheasive side of the gasket from staying put? Anybody's guess...
Anyway, thank you everyone for your suggestions. I must add that this thread had been more of a "pulpit" than a forum. I really believe that if the techs in Germany can build a 911 without leaking, I should be able to do the same. A lot of time has passed since my engine was originally assembled. Gasket sealing material has improved dramatically over that span. Still, I refuse to use "goop" that goes beyond the norms of engine assembly. The thru-bolt sealing rings did their job...I screwed up somehow on the spigot bore. Locktite 574 did its job. The cam towers are dry as are the case halves.
http://forums.pelicanparts.com/uploads/gasketleak.jpg

So, in conclusion, i guess this means that silicone is fine and not the supposed anti christ as opinioned by some on this post. Just curious since i like using the stuff on gaskets (especially cam housing gasket on 944's which can leak very easily onto the header if not torqued perfectly).

I didn't know that the cyl base gasket (as shown) had *any* adhesives on it. The ones I recently installed did not. Anyway, I coated them with a thin spray of Permatex Copper Coat for insurance. The adhesive will keep them from getting out of line as well. Wayne likes Curil-T for the same job.

Also...
"Locktite 574 did its job...."

And it's *not* a silicone.

Doug,
The top end rebuild kit came with base gaskets that were wrapped in plastic, individually mounted heavy paper. The adheasive almost feels like a tacky shellac, on one side only. I thought these things were supposed to be mounted dry.

They are supposed to be mounted dry. People use various tacky goops to hold them in place during assembly. I use a couple of pieces of masking tape.
-Chris

Thanks for that info, Werk!
I musta got riipped-off....the gaskets I bought came in gen-u-ine Porsche wrappers, but had *no* sealant of any kind on them. Slipped thru the cracks, I guess. Anyway *no* leaks there or anywhere on the 'Bomber's mill.

MISQUOTE!!! Don't quote me, unless you're 100% sure of what I said.

I recommend using the Loctite 574 on both sides of these rings as an added protection against leaking. I think that the Curil-T could be a little too thick here, where deck height and cylinder height alignment is very important.

All the cylinder base gaskets I've seen are pure copper with no sealants or adhesives on them.

-Wayne

The base gaskets I've used had some sort of coating on them. It was slightly tacky like a wax or weak adhesive. Perhaps it is just to keep protect them from corrosion?
-Chris

Where did you get the gaskets from?

-Wayne

Wayne,
It was a rebuild kit manufactured by Reinz AFM(or is it AFM Reinz?)

Wayne,
Not a quote, just a (wrong) recollection.
Don't blow a base gasket...ha, ha, ha!
Just wait 'til *you* get "Oldtimers Disease".

I wouldn't doubt it. It ain't a load of rubbish either.