bcameron59

Doing top end, heads came back from Steve Wiener on Friday. I was rotating the engine on the stand when I noticed the cylinders 4-5-6 had come slightly apart from the case (1/4 to 1/8" from one side to the other). I had totally forgot to put a spacer and nut on the stud to hold 'em down.

At the time I didn't think about it and was eager to get going, so just bolted the heads and cam carriers back on. Now I'm waiting for a tool (cam holder) to arrive and so have had a bit more time to think this over... and am now starting to worry that I may get leaks from the base/case join.

However I intentionally didn't want to go any deeper in to pull pistons, as I don't have the special tool for the snap rings on the pistons / conn rods. Seems to me I could either bite the bullet and pull it apart to replace base seals, or keep going on reassembly and start it up to check for leaks before fully reinstalling (although it will be about 90% there).

What would the collective wisdom of the board suggest?

TIA/Brian

Mike J

I would replace the base gaskets of each cylinder by popping out the circlips and removing each piston/barrel as a unit. The circlip tool is cheap ( Stomski has them http://www.stomskiracing.com/products.php?id=6).



If you don't do this, you know it will leak, its Murphy at work.. :-)

Cheers,

Mike

993Porsche

This is just to interesting not to ask. Can you show us some pics of where you are in the diss-assembly/reassembly?


Thanks,

Ken

AOW162435

Agree.



Andreas

AOW162435

Agree.



Andreas

Quadcammer

Most likely the seals are fine, but to do all that just to have a leak at the cylinder base would suck.

pull them, replace them, reassemble.

bcameron59

(Sigh) yeah I know you're right, I knew that's what I had to do the minute I actually thought about... But needed someone to tell me not to be a lazy esso bee and just do it.

Mike, thx for the tip on where to find the tool, now that I know what it's called I see it lots of places. I was getting nada looking for Porsche special tool 9500/2. So I'll buy the tool and pull the P&C's as a unit and put in new base seals with a smidge of curil-t for good measure. Any idea what diameter I need (96 varioram), or do I have to measure before ordering?

Also, do you think I can get away with re-using the cam carrier bolts and/or cylinder head gaskets, or do I need to replace one or both? I ended up ordering an extra set of head gaskets by mistake so am inclined to do them again, but am hoping I can re-use the bolts, they were $$ if I recall.

Btw pcarworshop has been a major source of guidance for this project, I literally don't think I could have worked up the nerve to do this (or actually complete it, though the jury's still out on that one). Since I couldn't make your annual bbq I'll have to figure out another way to buy you a beer in gratitude.

Thx again
Cheers/bc

bcameron59

I'll put a few up this evening after work, but if you want to see great pics and narrative of the whole process, see Mike J's pcarworkshop.com (link in his post, above), see "993 Engine rebuild" under Navigation on the left of the home page.

Cheers/bc

sonny1

To do it right, you will need new circlips too, cheers.
sonny1.

trophy

Brian,

Before you go and buy the base seals, i have some and I am also located in Calgary... PM me.

Mike J

I think the tool you want is for the 924, 944, 928, 968, all 911 84 to 89, 964, 993 - 23mm. You have the engine right there, so it would not be too hard to take a measurement to double check. Also, confirm to Stomski, they would know as well.

Not sure which bolts you are referring to - the ones that hold the cam carrier to the heads? You can reuse most of the bolts on the engine. Definitely replace the head gasket rings on each tightening, they are compressed and deformed on each tightening.

Of course, I should be have been more explicit, replace the circlips that you remove to take off the barrels/pistons. Obviously, keep the wrist pins and cylinders matched to the correct position on the engine. It will give you a good opportunity to check the condition of wrist pin bushings as well. Remember to be generous on the assembly lube when putting the wrist pins back in, and use a cloth around all the open holes when the clips are being inserted - its a total pain in the butt if you drop a clip into the engine...

I lubed the base gaskets with Dow Corning 111, and then used Curil-t right next to base gasket as well .. has not leaked yet.







Cheers

Mike

bcameron59

OK, as requested here's a few pix of my landlocked Alberta version of pcarworkshop.

Believe it or not this started out as a suspension refresh (M030 springs & ARBs, Koni FSDs). Also needed a new clutch soon, and had been throwing CEL / SAI error intermittently. So I figure, might as well do all that "while I'm in there" so I don't pay for a 4 wheel alignment twice...

the engine drop
the lump
the "upgraded" clutch fork shaft (with about 60K miles)!

bcameron59

the leaking RMS
one dirty engine (looking at this I'm thinking my cylinder bases were leaking already...)
the cam sprocket, soon to be backdated to 964 style

bcameron59

cam carriers - look at those SAI ports
SAI port on head - isn't there supposed to be a hole there?
exhaust valve

bcameron59

head / valves - before (I forgot to get an "after" pic but they're real purty)
pistons before - alla carbonara
there were pistons under all that!