Working on what I will now call Pandoras 914-6, I have managed to clean everything, find my #8 seal area leak and am dealing with it.

I pulled the clutch cause it looked a little oily and I located what you see in the photos. On a 914-4 I know there is an alignment dowel, but on this crankshaft, there looks to be a small metal plug. In that area, there is oil, and it matches the flywheel.

I noticed there is no felt washer like on the 4 cylinder...and obviously the flywheel ring is thicker so there probably is no felt seal. The main seal seems pretty dry, it appears to be coming from this hole.


Thoughts on this issue, I have never seen this before. Fixes?


Thanks as always

Photo #2 of the flywheel

Click to view attachment

Leaky crankshaft oil galley plug.

Fixes range from drill and tapped plugs to cleaning with brake clean and trying JB weld. I’ve also heard of aluminium plugs that are installed as a cold press fit into a heated crank - the theory being that once installed as steel crank heats up, the aluminium expands faster than steel increasing the sealing / press fit interference.

In all transparency - I have not had to address this on a 911 crank. Ollie’s did my crank but engine hasn’t been assembled.

If I recall - Bruce Anderson book doesn’t recommend pulling the crank plugs. I don’t see how you can guarantee no debris in the crank galley without removing the plugs. It’s a catch 22 IMHO. Hopefully I don’t end up in same situation when I finally get my engine assembled and running.

@superhawk996 thanks for the info. I think I will leave the plug there and try to epoxy / JB weld unless others chime in with another idea.

I did find other crankshafts online that have the same plug as mine in there, so mine is not unique. It must be an aluminum plug that just is not sealing properly.

Good luck with yours!

Rob

My only experience with a crank plug was about 3 years ago on one of our mowers that used a Kohler Courage twin (hey, it is air cooled). It was cutting fine, then all of a sudden began acting like the engine was overloaded. Thought I'd wrapped up something on the blades, so disengaged and started driving toward the shop. Halfway there the engine suddenly locked up. Upon disassembly, found the crank had eaten away the bearing surface on the aluminum block and basically fused to the melted glob that resulted from the friction. Turned out a plug on the crankshaft had worked its way out, and when it did, no oil pressure to the front bearing surface. I was able to salvage the crank by dissolving the fused-on aluminum with muratic acid. Amazingly the pistons were still OK, just needed a new block and a few odds and ends. Tapped and plugged the port on the crank with a brass plug and it's been running fine ever since. Last cutting was a couple of weeks ago.

Everything Superhawk996 said is right on with what I've researched about crank plugs. If it's seeping now, it will only get worse. It is under pressure and if it blows out, well, it's not good. If it were mine, and was 98% sure the plug was leaking, that plug would be removed, hole tapped, thorough cleaning of the oil galley, and a threaded plug installed. I do have a bias obviously from the previous experience. It may be preferred in the community to use a press-fit plug in this situation.

Dan

The good news is that the plug can’t blow out since it is backed up by the flywheel.

I’m just feeling bad knowing that this “project” started out with as a suspected front seal leak that turned into the dreaded #8 bearing leakage, that is now crank galley plug leakage.

On the flip side for dropping the engine and trying to address the leaks rather than just smearing RTV on the case and hoping for a miracle.

that galley plug appears to be peened. Is there a way to back it up with a long punch running into the oil galley and re-peen it to make it tighter?

Disregard: that would involve splitting the case . . . But if you do split case to address #8 then that idea might pan out

Thanks guys.

I believe it is not a plug but an actual solid dowel that is pressed in. From some diagrams I have seen and looking up replacement crank main dowel pins it looks like a pretty solid plug. Ill gently scratch at it with a scribe to see if it is aluminum or steel but the replacements all look to be steel. If that is the case, I can probably get it out easier and press in a steel one.

I have been cursing Porsche engineers the past few days. Why leave this as an "open hole" in the crank? The Type 4 has metal behind the dowel.... Unless it was drilled through by the rebuilder when it was rebuilt and plugged. The flywheel does not have space for a dowel, but I think the larger engined cars or the dedicated 911's with more bolt flywheels did.

Yes, the flywheel keeps it from backing out for sure.

I'll keep "plugging" away at this and see what I can discover.

Rob

Yup - same difference

Just like OEM galley plugs on the case. I didn’t necessarily mean to imply a threaded plug.

For whatever reason I thought yours might be brass but maybe I’m just seeing yellow tint in the photo as amber color of oil on it.

To get them out it’s usually a drill and tap operation and then the slide hammer. At least yours has a nice dimple to help center the pilot drill if you go the remove & replace route.

It’s not an open hole . . . It’s plugged

On a serious note, drilling and cleaning a blind hole is a bad plan from an engineering and manufacturing point of view. Therefore the galley is drilled all the way through, cleaned and then plugged. Very common.

Really no different than plugging holes on the case, carburettors, cam tower spray bars, etc.

I suspect whoever did yours didn’t press it or peen it properly. Not sure if that is OEM or a reworked crank. Like I said, when my crank came back from Ollie’s I could see all galley plugs had been removed and replaced.

If you dont replace it, clean it really well and try some wicking loctite before jb weld over it. Mine were leaking and I made new plugs and put in with 574 case sealant and I haven't seen any evidence of new leaking.
It also doesn't look like the seal is properly installed.

Thank you for that insight. The seal looks funny in the photo but it is ok. Im leaving it in till I solve this, then I will rip it out and install a brand new one that I have in the box.


My other alternative is to clean it real well, bust out the mig welder and seal it with weld and grind it flat. Wont leak then, but I am seeking less extreme alternatives first.

That is crazy talk. There are more bad things that could come of that than are worth the risk.

Flywheel end is # 1 Bearing,, Fan end is #8

Agreed.


Rob’s project also has a leaky #8 o-ring sealing problem (separate post) in addition to this leak on #1 end that is really a leaking crankshaft galley plug.

Carbide drills ordered. Will drill it, tap it and try to yank it out hopefully this weekend. I will then re-install a new plug with the appropriate wicking loctite.

Oh the joys of old cars. At least it is out of the car and I can get to it pretty easy. Now to take time, be patient and move slow.

Thanks for all the advice everyone!

Missed it..

not sure about others on here put the VR brand seal was a poor fit in my case ,very loose ,pulled it out and replaced with from what I can remember was an Elring or Sabo,not 100% sure.
Put the replacement in and it fitted like it should ,had no leaks when I pulled the g/box to replace shaft seal.
I would use JB weld as mentioned...seems like the only "safe" solution.

If you use JB weld just make sure you don't use so much that it is between the crankshaft and flywheel mating surface. This would cause the flywheel to be off balance.

Oh dear..away you go ,I can offer the best luck I have and can give you.

Thank you to all for the "Luck".. it must have worked.


I got the plug out. Carbide tip bits, drilled, tapped, heated the crank to expand it a bit and a slide hammer. I havent taken a photo yet cause I am still breathing hard from the experience.

Tomorrow I go to International Metal Supply in Burbank and source some aluminum round stock to make the next plug. It will be a similar route, freeze the plug once fabricated and sized to shrink it a bit and then tap it in with wicking loctite.

I have to make the plug as the mouth of the opening is just over 7mm and there is a slight taper down to 6.88 mm. So some fitting will be necessary but according to a Porsche engine guru who was nice enough to advise me, the aluminum dowel is the preferred way to go.

This motor will be rebuilt in the future, I am just still enjoying it till that time comes. I have a 2.4 with triple webers and E cams that may get swapped into the car while this one goes through that process. I do like the drivability of the CIS.


The VR seal is coming out as well, and I have a new Erring seal to put in its place so I am confident it will seal up.

The #8 bearing will be a fix with Tom Amon's bearing seal kit not using JB weld, but another sealant. This will button it up for now.

Finally it will get the tins painted, the fiberglass shroud repainted, new gaskets for the triangle of death and the IMS cover and new oil cooler seals. There isn't much else to leak at this point. I ll photo it when it's done. New clutch arrived as well so my confidence level is back up to "moderately high"....

The World is great and I appreciate the advice within. Thank you all, truly.

When you install Aluminum plug:

Freeze plug as you stated to shrink it.

Gently reheat crank above room temp to expand it a little but not so much at it will mess with any Locktite you might use.

Make thermal expansion & contraction work for you in both directions simultaneously. . This will allow you to maximize the interference fit and still be able to install the plug with reasonable ease.

Install galley plug

When all that is done, then replace your RMS

Ok... bringing it nearly full circle.

I fabricated up my new aluminum dowel out of 6061 Aluminum rod. I made it so it was slightly tapered so it would start in the hole easier. Put it in the freezer for 3 hours.

Just prior to installing it with some loctite, I heated the crank with a propane torch. Nothing too hot, but enough to wake it up. I left the old seal in place so when I could start to smell it a bit, that's when I stopped.

Ran to the freezer, grabbed the dowel and hammered it home. It was certainly a pressed fit but it seems to have worked great.

For any of you reading who want to know what happens "while you're in there... here is the list so far:

New crank dowel to stop clutch leak
New flywheel
New Pressure Plate
New disc
New Throw out bearing
New clutch fork busing
New intake gaskets
All new rubber hoses associated with the CIS and heavy duty plugs for vacuum block off.
New rear main seal
New front pulley seal
Tom Amon's #8 bearing re-seal kit
New fasteners
Painted tins
Valve Adjustment
New Fan belt
New gaskets for IMS cover
New gaskets for breather cover
New oil pressure sending unit

And there is a "still to do list"....

Click to view attachment

Well done,don't remember but pretty sure I hand a roll pin in that hole ..could be wrong or its different with a 2.7 ?
Appears to be some sort of sealer on the end of the crank appears someone in the past used this to patch a leak ???.

By all the Fretting around the mounting surface and bolt holes , its had a loose flywheel at some time ..

Well, it was tight when I removed it. Who know the history of their used car?

In any event, the DAPO used a silicone in the bolt holes so some of what you see is that on the surface of the metal. Once I scrubbed it with a wire brush and brake cleaner, and chased all the holes and cleaned all the bolts, it torqued down nicely. I'm hoping I have dealt a blow to the leak at this point.

Bolted up the clutch pack today, installed the fan, the alternator, the shroud and started re-doing the wiring harness a bit to make it cleaner and route it better. I am hoping to shoot for a Sunday Install, but life gets in the wait.