new base gasket problem

[mahoneygod]

So I am replacing my base gasket on an 02 S4. It got bad enough to leak down the back of the case and in the path of the tire. I removed the head and the cylinder came with it. I cannot get them separated. Any ideas? I bought a whole gasket kit and wanted to replace everything while I was in there. Will also be picking up new hc pistons from fbf.

[Speeddog]

Seems they get some corrosion on the locating ring-dowels and get pretty stuck.

I plugged the oil gallery on my S4 with a 10-24 setscrew and oil-resistant threadlocker.
Grease the drill and tap to keep the chips out of the gallery.

If you end up not getting the hi-comps, be *very* careful with the OEM oil rings, they're cast iron and very fragile.

[ducatiz]

rubber mallet

try to leave the piston in the bore of the cylinder.  it's a trick, you have to pull it up enough to clear the pin. 

i replace the pin keeper with snap rings.  always.

tap out the pin and hoopla, you lift it all off.  gives you more room to inspect inside the case too.

[mahoneygod]

What should I be looking for inside of the case? This is my first time cracking into a Ducati engine so all this is pretty new. Thanks for the snap ring tip will definitely do that.

[ducatiz]

can't tell much by eyeballing things but you can check the end gap on the con rod big ends.  good time to put in some carrillos too.. :-)

[mahoneygod]

If I install the hc pistons do I need to make any changes elsewhere on the bike, ecu, throttle bodies, plugs, valves?

[ducatiz]

nah.  i would put a PCIII or similar on it and run it on a dyno though.  you can get by without it, but the bike isn't going to be running at potential.

[mahoneygod]

How much is it usually to get it dynoed?

[ducatiz]

depends on the shop.  most want to charge per run or per hour.  i don't trust the per hour setup.  one guy can get your bike up in 20 minutes, another guy is dumb and takes an hour.    YMMV

[mahoneygod]

So i couldnt get the cylinder and head apart with just a mallet. So i crafted a wedge out of an old plastic tire lever, worked like a charm. hc pistons show up sat and shortly after that i guess im going pc III then dyno. thanks for all the help guys.

[mahoneygod]

What kind of sealant should I use on the base gaskets?

[Howie]

TriBond, YamaBond, Whomeverbond.

[ducatiz]

With all due respect to Howie, for the cyl base I would use permatex aviation form-a-gasket #3.  It is particularly suited to this area.  It applies with a brush like honey but slowly sets up.  Put a thin coat on each side of the gasket and let it sit for about 5min until it gets tacky.  Then put it on and torque down the head.

Make sure to apply it to the outside ring of the gasket so it squishes out when you torque it.   That will make a bead on the outside.

It will never ever leak.  The only downside is that its a pregnant dog to remove.  Acetone and mek.

I've used it on engines for over 20 years.  Far superior to any rtv silicone. 

It's for piston aviation engines.  It has to work.  Rtv is not permitted on aviation engines not the head or cyl gasket anyway.

[Howie]

With all due respect to Howie, for the cyl base I would use permatex aviation form-a-gasket #3.  It is particularly suited to this area.  It applies with a brush like honey but slowly sets up.  Put a thin coat on each side of the gasket and let it sit for about 5min until it gets tacky.  Then put it on and torque down the head.

Make sure to apply it to the outside ring of the gasket so it squishes out when you torque it.   That will make a bead on the outside.

It will never ever leak.  The only downside is that its a pregnant dog to remove.  Acetone and mek.

I've used it on engines for over 20 years.  Far superior to any rtv silicone.  

It's for piston aviation engines.  It has to work.  Rtv is not permitted on aviation engines not the head or cyl gasket anyway.

That'll work.  So will TriBond.  A light smear has worked on my bike for over 9 years and 50 someodd K miles.  Tribond is some sort of semi hardening poymer.  I totally agree with you about RTV, as i think anyone would who worked on cars in the 80's.

[mahoneygod]

Ready to put the pistons in tonight. Is there anything special i need to do to the cylinders or pistons besides sizing the rings? Has anyone put in the hc pistons from fbf?