Searching for an air leak

[TavisB]

My 03 EC250 was sitting for a bit (bought a Berg 390) and when started developed a very high idle that I couldn't get rid of. It was due for a top end anyway, so I did a piston and rings, new air boot, and new reeds.It's all back together now, but I want to do a leakdown test on it to make sure there isn't an air leak before I trash a brand new piston. When I try to pressurize the engine, the air is all just rushing out the powervalve drains. Is this to be expected? Do I need to block off more than just the exhaust and spark plug hole to get a good test? Or does air going through the powervalve assembly indicate something?

https://www.youtube.com/watch?v=HczLoT2Um_4

 

[Zman]

I would also check out the crank seals on a bike of that age.

 

[Simmo737]

You need to seal the pv drains

 

[TavisB]

Ok, thanks. Wasn't sure on this bike. Have new crank seals on the way already, I suspect they are the source of my leak.

 

[Moto7man]

Here is a complete thread on my 2015 rebuild including how to build a leak down tester with specific instructions. Go to post #19.

http://www.gasgasrider.org/forum/showthread.php?t=19892&page=2