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Discussion Starter #1
While tearing my motor down to replace a leaky base gasket, I also put a wiseco hi comp piston and rings in. All went well and I was up and running. Probably around 1000 miles in it started leaking oil. It is spewing it out now and it is time to fix it. It only spews oil when running or so it seems. Looked like it was the main shaft seals. Ordered a seal set a while back(winderosa brand) replaced the outer seal, still pushed oil. Pulled cover and replaced inner seal and thought for sure that would do it, nope. Ordered oem seals and put them both in at same time and ploblem solved! Week and a half later its back and gradually got worse.

The shaft surfaces looked good, and everything looks to be in order. I doesn't have too much oil in it and has new case gasket. The neutral switch looked dry every time the cover was off. Is it possible a venting issue and maybe that is why it only spews when running? I ride on the freeway about 12-14 miles each way to and from work every day(14/45 gearing) and did this all last year with out any problems.

Any help figuring this out is greatly appreciated.

Thanks, John
 

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Discussion Starter #2
Mike,
Thanks for jumping in and yes it is the shaft with the front sprocket. I doubt it is bent as the cover always slides on, but anything is possible and I will check it. I have a toolkit similar to the Admiral's, but didn't use it to replace seals or install side cover. Remember it only leaks when the motor is running, WOT most of the time and you can't see anything when at idle. It is pushing enough oil now that it will drip off the swing arm.... The chain likes it, but the driveway does not.... I am going to take the skid plate off and try and get a closer look. Could a tight valve lash possibly cause blow by and cause breather problems? Anyway thanks again.
 

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Over filling the oil cause it to "blow out".

Excessive blow by too -- are your new rings seated and sealing? If ring gap is to little and if it over heats the rings expand and can cause damage leading to excessive blow by. This is the worst case most pessimistic scenario.

What size Wiseco did you use? What did you set the piston to cylinder wall clearance at? What were the ring gaps set at? What are your impressions of using a Wiseco?
 

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If it is only leaking when the engine is running above idle speed, then I would suspect the output shaft seal which is on the stator side cover. This outboard bearing is supplied oil through the output shaft and this oil then drains around the stator and back into the crankcase as shown by the red wire in the picture below. The outboard bearing and seal are located under the metal plate on the left side of the side cover in the picture.

100_4764.JPG
 

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Does some of it look fresher/wetter/cleaner than the rest? Mine has had to be replaced 3 times so far, and I was able to see it with a flashlight first. Keep us posted. TW-Brian is pretty darn good at this kind of stuff, so he might have it nailed if it is pumping out while running. Hope you get it figured out soon bro, these kind of things are so frustrating.
 

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Discussion Starter #9
Over filling the oil cause it to "blow out".

Excessive blow by too -- are your new rings seated and sealing? If ring gap is to little and if it over heats the rings expand and can cause damage leading to excessive blow by. This is the worst case most pessimistic scenario.

What size Wiseco did you use? What did you set the piston to cylinder wall clearance at? What were the ring gaps set at? What are your impressions of using a Wiseco?
Oil level is good if not low, I thought the same. Piston to wall clearance(stock bore) was right in the middle of tolerance after honing. Was surprised how round and straight bore was. I forget what the end gap was but in spec. Rings seem to be seated just fine, it doesn't smoke at all. After 2200 miles it seems all is fine with top end and I am happy with the piston. Maybe a leak down test or compression test may tell me something?


TW-Brian,

I have replaced that seal and the other one with the winderosa seal kit and it leaked, thought they were bad. Replaced them both with oem seals, new gasket and it was sealed for 200-300 miles and started leaking again and progressively got worse. I am really at a loss because replacing the seals is pretty basic and straight forward or so it seems..... I can wipe it down and it won't drip a drop at all.

Thanks everyone for the help, I am sure we will figure this out.
 

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Discussion Starter #10
Does some of it look fresher/wetter/cleaner than the rest? Mine has had to be replaced 3 times so far, and I was able to see it with a flashlight first. Keep us posted. TW-Brian is pretty darn good at this kind of stuff, so he might have it nailed if it is pumping out while running. Hope you get it figured out soon bro, these kind of things are so frustrating.
Was that the side cover seal you replaced three times? It makes sense that if the oil drain hole TW-brian pointed out was blocked it would push it out the seal with no where for it to go. The side cover is coming off.
 
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