sample technique w/ pump

[sky jumper]

so I normally sample with engine hot, soon after it has been shut off. I mark the dipstick length on the fresh hose, and put it down the dipstick hole no further than the dipstick length.

questions:

1)is there a better way to do this -- in terms of how far to insert the sample tube? should we ideally sample from the middle of the sump? I'm guessing I'm drawing from the top 20% of it. do the wear metals "settle", or are they dissolved uniformly?

2) does anyone have any evidence so suggest drawing a sample from a cold engine will skew the results (aside from fuel/water)??

thanks!

 

[lindermant]

1) can't say for certain, but I'd think wear metals would be pretty uniformly mixed up while at temp.

2)

but it sounds like a good opportunity to test it and report back

 

[Norm Olt]

I asked a similar question earlier: I guess I just don't see why taking a sample (I suggested using a piece of clear plastic tubing, kinda' like an "Oklahoma Credit Card") from the oil (sampling from middle of the container: not the dregs on the bottom) after it has been drained into a CLEAN drain pan.

I guess I don't see the real advantage vis'-a-vis' the pump nor the catch bottle under the stream methods. Gonna' still use a tube with the pump, eh?

Cheers!