T500 Leak Down Testing and Bad Results

[smoker]

Hello All - I have recently replaced the crank seals and resealed the case halves with 3bond 1211 on my '71 Titan. Before reassembling the entire motor I attempted to leak down test. I have performed this on various single cylinder mx bikes in the past so I have the equipment and some knowledge. Plugged intake and exhaust with expansion plugs, blocked oil intake lines with screws and o-rings. The left side checks ok at 6-8 pounds but right is losing air immediately (also at 6-8 lbs.). The crank seal seems to be ok, no soap bubbles. The air seems to be escaping from somewhere back farther to the transmission. I read after assembly (of course) that the center bearing is lubed with transmission oil. If this is correct, from my failed leak test is it safe to assume I have a case leak between the transfer and transmission sealing area or a bad center seal? Totally overlooked replacing this as it did not come with my seal and gasket kit and I was not aware of how it was lubed. It seems odd to lose air this rapidly from either source but I leave this to the experts - please advise, oh wise ones...

[Coyote]

I am surprised, almost shocked that you have not gotten any response in this amount of time. I wish I could help, but about all I know about a T500 is it's a twin.

[parksie]

You're right in assuming that it's either the center bearing seals or a case leak. Which ever you are going to have to pull it apart again. When you have it apart spin the centre bearing and see if there is any resistance, it should have some resistance if the seals are still Ok. To loose pressure that quickly I would look at the sealing in the crankcase or even the Orings around the centre bearing, you may have pinched them when you put it back together.
And yes the centre bearing is loobed by the transmission oil. When putting it all back together make sure that you don't block the lube path for the centre bearing with 3bond.

[smoker]

Thanks. I have kind of resigned myself to it being the center seal and since I am opening her back up I intend to replace it regardless of what I find. Coyote - I had assumed the delay was due to this being a dumb question! Denial will do that to a person Any recommendations on who to perform the crank work would be greatly appreciated.

[oldjapanesebikes]

As you are based in the States, try Bill Bune (http://www.billbune.com/" onclick="window.open(this.href);return false;) . A number of folks have used him and seemed happy with the results.