Gulpilen

Is it possible to change the seals with the engine still in car and with the cylinder heads still on (using compressed air to have the valves in place)?

What tool can I use press down the springs for removal and installation if above is possible???

/Jonas

Dave928S

Yes it's possible. It's difficult and time consuming but you need a tool like that shown in the WSM.
Here's an example that will work .... http://www.tooltopia.com/schley-91400b.aspx

Gulpilen

Perfect, thanks. 9225/1 special tool.... Is that tool buyable at all - at Porsche or somewhere else?

davek9

Don't forget to use valve stem condoms to protect the new seals when installing them over the valve stems.
Also if the seals are bad, the valves, pistons & heads should be cleaned of build up IMHO.

Dave

Lizard928

Yes, I've done the job while installing new camshafts. Plan for 16-18 hours of work.

Rob Edwards

9225/1 was 'only' $26 when I bought one in 2009, part # 000 721 922 51. My guess is they're still available. (FWIW, there are two flavors of these, one has a little 'nub' inside the cup that the seal slips over; the nub pokes into the stem seal and down the valve guide opening, which eases pushing the seal in place. Note that the picture below is NOT that variant of the 9225. Not sure how to ensure getting the 'right' one).



Colin- For compressing valve springs 'in-car', I wonder whether the factory 9242 tool might be an easier solution that the Schley bar-type compressor, just in terms of the speed at which you can move from spring to spring? Or is that the least of one's worries?

Here's the 9242:





EDIT: For getting the old seals out, it can be a real bear. The factory tool is insanely expensive, the Schley 92350 pliers are ok but for the same price there is a better tool, see this Ebay link:

http://www.ebay.com/itm/New-T-Handle...6d9cc0&vxp=mtr

Lizard928

Rob,

That 9242 tool doesn't work. Or more so, not with that factory leg.
Also you will need to have it rewarded as its too soft from factory.
I spent 6 hours doing 2.5 cylinders with that tool. I then made a new piece and rewelded it and did the rest in 2 hours.

I now have the bar tool listed and will be trying it on Jeff's car.

atb

So what is a valve stem condom?

I found this R-List thread with a part no., but anyone have a pic?

https://rennlist.com/forums/928-foru...em-condom.html

Speedtoys

What can go wrong??

Lizard928

Nothing really Jeff. I will be bringing both tools.

Speedtoys

I dont think I can get Greg Brown to show up and provide a religious blessing, or Roger to come with a large van of "WYAIT" parts..or _even_ Kibort to just stand there and provide an even comforting light beaming from the glow of his recent application of Amsoil Hawaiian Man-Tan lotion...

However, I did find this on the interwebs. I hear it's good stuff.



At some point Bishop Bill Ball should arrive to preside over either the funeral or the birth.

Gulpilen

atb, I just searched for valve condoms and got a pic on it in a thread started by 993turbo. I am investigating all the possibilitys, thanks for your support.

Lizard928

I have a number of valve stem condoms at the shop, I only ever need 1 maybe 2 per job.

And yes, getting the stem seals off can be a real B*TCH. I took a 12mm wrench and bent the open end so that it slides under the seal and I can then rock it and it pops it off, I have the factory pliers and they are bloody useless!

Imo000

On the '85, I had one hell of a time pulling the steam seals too. It was much easier on the 996. Porsche must have learned to fix this as some point.

Rob Edwards

I'm tellin' ya, the Ebay special I linked to above is the shizznit for valve stem seals. Adjust the conical setscrew thingee for the proper degree of 'grab' , then rotate the clamped seal a couple of times to loosen it, then rotate while lifting on the T-handle, they pop right off, no risk of scratching the lifter bore. In comparison the Schley pliers are a giant PITA.