PCM 1.23 Leak

So the 1999 Sport Nautique project boat has started puking trans fluid quite often now and out it comes. A experienced mechanic can have it out in about 30 minutes for those of you who want to tackle the job yourself, other wise give your buddy some beer and expect a hour or so.. I would like to post pics of the front pump seal because I haven't seen a picture posted recently.. [/IMG] [/IMG]

SNobsessed wrote: Do you know why the seal failed yet?

My guess Chris is 800hrs on it lol.. I have it at work now and took the seal out and there is just a very slight wear groove on shaft were the seal rides.. I was able to smooth it with emery cloth..

8122pbrainard wrote: Joey, I sure would consider a speedy sleeve on the shaft. Good luck with the seal. I hope the pump isn't worn past tolerance pressurizing the area behind the seal.

After closer inspection Pete the shaft had more of a crud ring around it from the longtime leak more than a groove.. I measured the old seal verses new one from Ski Dim and it had expanded almost 1mm do to its age.. And yes I hope the pump isn't worn either after all the Engine issues and interior work trans parts are not in the budget 😔

Ok so apparently the leak is still there but slowed down alot.. I noticed my Damper plate has so movement to it, and the input shaft on the trans has very slight movement as well.. so the front pump seal technically doesn't have a true turning shaft to ride on the the damper is worn..Correct me if I'm wrong Eric.. Looks like it will be coming back out for a new damper plate.. Shame on me for not replacing it while I had the trans out the first time. 😩

Chris, yeah that makes since to do a final torque of the bolts once trans is installed.. like a auto clutch pressure plate where u have a alignment tool.. we have no such thing with our boats unless u make your own from a junk trans case and shaft somehow.. As far as I can tell it was the original front pump seal that I replaced. And the damper plate appears to be original too with 800hrs on it.. So with it having the play that I observed that's gotta be causing movement on the trans shaft causing the slight leak.. It would be the same senario as a engine crankshaft wobbling on the front engine cover seal in my mind.. it's gonna leak oil.. I just can't stand having anything other than a little water in my bildge so I gotta get this fixed..

KRoundy wrote: Although I always wonder about the fact that this puppy is held on by three bolts apparently? I'm sure Pete will tell me why that is OK compared to the circular flywheels available from SkiDim.

It's all about the shear strength of the 3 shoulder bolts. With a tensile of around 150,000 psi, they can easily handle engine torque.

8122pbrainard wrote: Joey, The damper adds no support to the trans input shaft. In fact, it's made sloppy and spring loaded and the reason a common name is a "flex" plate. It's there so engine vibrations aren't transmitted to the trans. All the support of the input shaft comes from the trans itself. What happens with a worn damper is it will put a radial load on the shaft in one spot say if it has a broken spring)s).

Pete understand what you are saying, but my thinking being if the input shaft going into the damper plate has slight play.. and my damper has some play then the shaft has no consistent surface and if it does vibrate any at all fluid is gonna go right past the seal.. Vince at Ski Dim was telling me the damper was suppose to be rock solid on the springs.. no back and forth movement by hand he actually pulled a new one off the shelf while we were on the phone and said the center hub on the damper had no play in it..

NAUTIQUEjunky wrote:    Vince at Ski Dim was telling me the damper was suppose to be rock solid on the springs.. no back and forth movement by hand he actually pulled a new one off the shelf while we were on the phone and said the center hub on the damper had no play in it..

"Rock solid on the springs" Wow, I want whatever Vince is smoking!    

And Pete I have no experience with damper plates.. After all the inboards I've owned I've never had one go bad or had to pull a trany.. I'm just going by what Vince said.. I personally would think a brand new Damper would have little to no movement on the hub if you tried to twist it back and forth by hand.