250R leakdown test ?

[3wheelrider]

I realized (afterwards) that i had the piston at TDC not BDC when i did my leakdown on my 85 R (shortrod with fresh topend & left crank seal. -Is my test no good. I wont be able to retest till next weekend so i cant just redo it right now & find out. -so i thought id ask....:wondering
It did hold 6psi fine- but dont know if the ports were blocked thus -test no good???? havent started it up yet-outta time.....

[nicker71]

Piston position doesn't matter with a leak down test as far as I know. I can see where it would be better to have it down though.

[yaegerb]

Are you talking about a crankcase pressure test? If so it should hold 6 lbs for 10 minutes regardless of where piston is setting tdc vs bdc.

[3wheelrider]

I thought that the piston position was important during leakdown tests?-maybe not???
But I thought Ive read it before somewhere on 2 stroke leakdown procedure that tbey specify one or the other position? ???

[3wheelrider]

Yes-it held 6psi for at least 15 min.

[3wheelrider]

I had the sparkplug installed/test was done thru intake manifold...( while piston was at TDC)
So Im good???

[yaegerb]

Yes, you are fine.

[3wheelrider]

Thank you....