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Power valve sealant mystery?

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Noticed loads of sealant around the base of my power valve cover a while back which had been worrying me about 6 months after a shop had done the top end for me. Now I'm removing the sealant and wonder what could have been leaking out of there .... pre prix oil from a faulty seal? Its ugly!

This is my first time doing a top end.

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It's no mystery. I believe there should be a rubber gasket that goes there between the cover and the case. Whoever did the rebuild was too lazy or didn't want to spend the small amount of money to make it right. ImageUploadedByThumper Talk1402792540.389087.jpg

Buy part number 33. It's $5

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Just powervalve goo mixed with condensation....whoever did that top end is a hack if they sealed it like that.

 

def get a new gasket. Theres also an oil seal...21 on that pic...supposed to seal that area from getting any more goo in there. 

 

And then you will have a happy little yz.

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It's no mystery. I believe there should be a rubber gasket that goes there between the cover and the case. Whoever did the rebuild was too lazy or didn't want to spend the small amount of money to make it right. ImageUploadedByThumper Talk1402792540.389087.jpg

Buy part number 33. It's $5

 

Thank you Bremer120, I've just ordered a new rubber gasket from here .... http://www.ebay.co.uk/itm/350700981789?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

 

I can't believe I paid good money for their work.  They also replaced by suspension fork seals, taking 6 weeks in total, fitting the wrong seal to one of my forks and putting the wrong amount of oil in.  It meant my forks were really hard and leaked oil after just a couple of rides.  Had it redone by Boretech in the UK and now my suspension is perfect.  

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Just powervalve goo mixed with condensation....whoever did that top end is a hack if they sealed it like that.

 

def get a new gasket. Theres also an oil seal...21 on that pic...supposed to seal that area from getting any more goo in there. 

 

And then you will have a happy little yz.

 

Hey Jeff, thanks for the advice about the oil seal.  The oil consistency almost seemed milky white.  Wouldn't oil from the powervalve be black or darker?  It smells more like transmission oil.  Just wondered if it could be a leak from the left case via the governor rod?  There's an oil seal there, which is number 7 on the following diagram.  What do you think?

 

http://www.yamahamotorcyclespares.co.uk/genuineparts/13151/2/yamaha%20yz125%20-%2013151/governor?uID=0

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Totally right. Now that i look at it closer, i dont see any power valve goo draining from the top. seems to all be on the bottom, right? The powervalve is usually the leaky guy in most cases. Stuff seems to get everywhere, thats why i assumed. But ya...if its not leakin from up top, that lower one looks to be your culprit. Take a look at the other sealing surfaces too...theres a few of them that all seem to meet right there.

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Totally right. Now that i look at it closer, i dont see any power valve goo draining from the top. seems to all be on the bottom, right? The powervalve is usually the leaky guy in most cases. Stuff seems to get everywhere, thats why i assumed. But ya...if its not leakin from up top, that lower one looks to be your culprit. Take a look at the other sealing surfaces too...theres a few of them that all seem to meet right there.

 

Yeah, it's all in the bottom and bone dry up the side.  So I think I'll focus on the lower governor seal and check out the other sealing surfaces, as you suggested .... the side case gasket runs straight through that bowl so that's a possibility.  I'll let you know how I get on.  Thanks again.

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