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Front Crank shaft seal on the timing chain cover leaking

It's the standard rotation. Counter clockwise viewed from the flywheel. Im going to try the universal seal next. Nothing to loose but my time.
 
Talking to a buddy of mine last night and explained my leak situation to him. The engine doesnt leak at low 600-1000 rpm. I can harbor cruise all day long without a leak into my catch pan/oil diaper when I run her up to my cruising range and run at about 2300 to 2500 rpm the engine leaks. My buddy suggested the trouble could be the harmonic balancer. The rubber could look ok to the eye but when the engine starts to run at a higher rpm the centrifugal force created by the added rpm starts making the outer ring move and become unbalanced. Causing enough vibration to ooze out the oil. What say you guys? Its a thought and the part is 60 bucks at NAPA.
 
Did you replace the timing chain cover perimeter seal? I don't see that in my review of the story. The TC seal is critical where it hits the cast oil pan, at the corners and during the full length of the curved section. That entire length needs rtv to seal. THe sand cast oil pan is rough and requires sealer. Leaks here get mistaken for the rotary seal leak. If your worried with the "outer ring" vibration thing, shine a timing light on it to look for this vibration. I don't think the vibration would bend the crank enough to leak the seal, but I guess stranger things do happen. If the engine feels smooth in neutral to 3500 rpm, I'd not worry about that.
One last thought. I really can't imagine a new rotary seal with a smooth mating surface leak as fast as your leak. On the other hand, i've lost a quart of oil / hour with a brand new pan to TC seal, with NO RTV.
 
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Any Blow-by issues??? Crankcase properly vented??? Crankcase pressure (if venting is not working) will contribute to seal leakage.
 
jclays said:
My buddy suggested the trouble could be the harmonic balancer. The rubber could look ok to the eye but when the engine starts to run at a higher rpm the centrifugal force created by the added rpm starts making the outer ring move and become unbalanced. Causing enough vibration to ooze out the oil. What say you guys?
Click to expand...
The harmonic balancer offers a machine fit onto the crankshaft.
The crankshaft is supported by the main bearing journals.
Each of these fits are precision and are of low tolerance.
In order for vibration to cause the front seal to leak, tolerances would need to be excessive, and if excessive, you'd be having much larger issues.

Is it possible that the seal location within the timing chain cover is not true, and/or may be off center some?
If you end up pulling the cover, why not try another known-to-be-good cover?
 
Have never pulled the cover off. Leak started around May. Never leaked before. Cant see the lower front of the timing chain cover or oil pan. cast steel yoke style motor mount covers that up. Will have to lift engine to do so. Straight shaft no u joint in it. Perpendicular line of oil to the engine indicating it is being slung by the crank or balancer.
 
jclays said:
Perpendicular line of oil to the engine indicating it is being slung by the crank or balancer.
Click to expand...

Yeah, it does sound like the seal is leaking (not big news, I know). Is the cover is good shape otherwise? Sometimes they do rust thru with a pinhole, if it was above the seal, you might still sling it. Did the latest seal go on OK, that is, without a lot of cocking, with light sealer applied to the perimeter? Engine oil on the damper seal surface just before assembly.
 
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