Failed base gasket?

[mtnmanseth]

I was cleaning the bike last night and noticed a new oil stain on the right side of the cylinder jug base where it meets the main case. You can see a shiny patch (~1/4" wide) that may indicate gasses escaping through the gasket? Does this mean it's time to drop in a new top end kit (w base gasket)?

 

[(F5)]

Yes, yes it is. But I'd pop it off before you buy too many parts, depending on how long since the last rebuild. I just did my base gasket for same leak. My rings were well within specs, so I tend to measure first order later.

 

[mtnmanseth]

Thanks for confirming, F5, as I'm new to 2-strokes so even obvious answers are appreciated. To make a long story short, I'm the 3rd owner of my bike but the former 2 owners maybe put 40 hours on the bike (in 9 years!) and since I've owned it have put another 100+ on it. I know it's time. So now I'm researching about how to do a top-end replacement (my first time) and what brands guys are liking. I'm leaning towards Wossner.

Anyway, the bike overheated on me for the very first time over the weekend. Very steep prolonged climb with a lot of clutch abuse. First time coolant ever came out of overflow tube. I shut off engine immediately and let 'er cool down (she started right up 20 mins later). Do you think this heat condition may have caused the gasket failure, which likely is the stock one?

 

[mtnmanseth]

Another question:

My jug has an "A" stamped on the back, okay... so should I order this complete kit off eBay with an "A" piston?

http://www.ebay.com/itm/TOP-END-WOSSNER-PISTON-KIT-A-GASGAS-300-EC-XC-SE-300-WILD-300-GAS-GAS-/361102994476?pt=Motorcycles_Parts_Accessories&vxp=mtr&hash=item54136a6c2c

Or, considering I really have no idea of the condition of the cylinder and PV guts, etc, should I wait to pull it off and then pay a machine shop to measure the actual cylinder? Then I can determine whether an "A" kit is really what I want? Or just go off what's printed on the jug?

Of course, I'm trying to spend as little $$$ as possible, and living in SoCal the best time of the year to ride is NOW, so I want to get this done quickly, but correctly. Again, many of you are 2T top end experts, so any hints about prices, chronology, etc would be very valuable at this point.

Thanks in advance...

 

[bowhunter007]

As F5 indicated, pull it down and inspect all related components...1st. Take some detailed pics, and post them if you need additional help or answers.

 

[(F5)]

Stuff should be available quickly. I'm keen on woosner. They come apart easy, just read the PV instructions on the tech articles and clean it. But melt the nylock but under the barrel PV cover first. I bought cometic gaskets as easy online but std are the go as well.