Sport 1100 crank seal

[dxhall]

My rebuilt Sport 1100 motor keeps leaking from the front crankshaft seal.  I've replaced the seal twice, but it still leaks.  Any ideas?  I'm about ready to pull the front covers off again.

[rodekyll]

If this one has the ducati alternator there's a spacer behind the rotor and an o-ring behind the spacer.

[Antietam Classic Cycle]

What he said. Though I think the o-ring is in a groove in the bore of the spacer. The o-ring is #7, the spacer is #8 on this drawing:

[rodekyll]

I see what the picture shows, and my mind still thinks the o-ring is on the other end of the spacer.  I've got all that out in the totes, I should take a look.  In the meantime, when you get into the general neighborhood, it will be the only leaking o-ring you see.

[edit]

I got lazy and looked it up.  Here's a pic from Greg Bender's site showing the o-ring where I remember it.

http://www.thisoldtractor.com/mg_photo_archive/engine_crankshaft_and_main_bearings/00710.jpg

[dxhall]

The o ring fits in a groove on the inside of the spacer.  I replaced it, but I suppose I could have the wrong size.  I'm wondering if a restricted breather could cause crankcase pressure to build up and cause this.

[Antietam Classic Cycle]

I see what the picture shows, and my mind still thinks the o-ring is on the other end of the spacer.  I've got all that out in the totes, I should take a look.  In the meantime, when you get into the general neighborhood, it will be the only leaking o-ring you see.

[edit]

I got lazy and looked it up.  Here's a pic from Greg Bender's site showing the o-ring where I remember it.

http://www.thisoldtractor.com/mg_photo_archive/engine_crankshaft_and_main_bearings/00710.jpg

The crank in the photo is from an Eldorado.

[rodekyll]

That would explain the mixed up memory.

[guzzisteve]

If you have the PCV valve type ball in tube, it can get stuck and blow your seals from too much pressure.  That's why my Cal2 leaks, changed the valve but not the seals. Check your frame too for obstructions also.

[pehayes]

 :1: o-ring is in a groove inside the spacer.  Had the same issue replacing the seal on my 98EV until I discovered the o-ring.

Patrick Hayes
Fremont CA