Retreiving oil sample through dipstick

[ragingfish]

Has anyone else been successful at using a vacuum pump through the dipstick to retrieve an oil sample? I want to send some in for analysis but the tubing only goes down so far and then hits something. I can't figure out what the problem is, I tried twisting and turning and everything, but I just cannot get it down to the sump.

Any thoughts?

[wreckwriter]

Try going through the filler cap?

[ragingfish]

Yeah, tried that too, but the tubing is too stiff to maneuver. There's some plate or something directly inside the cap that I would have to get past.

[GXPaycheck]

Same issue with me. Can't do it on the LS motors for some reason. Fumoto valve would be the best thing if you want to do samples between changes.

[jab]

I have fumoto valve on all my cars....great investment