Whats Your Oil Sampling Technique?

[BBDartCA]

What are most people here using for an oil sampling technique (i.e. getting a sample when not changing oil & filter)?

Using a Mityvac or other suction devise to suck up oil thru the dipstick tube? Draining a little bit of oil from the pan?

For people sucking oil out, are you replacing the suction hose each time to help minimize contamination?

 

[Gary Allan]

I use a viper pump from Blackstone. New piece of tubing every time. I basically measure the dipstick and about another foot and a half for handling.

 

[ronrackley]

Originally Posted By: BBDartCA
For people sucking oil out, are you replacing the suction hose each time to help minimize contamination?


When I "suction" it out with the Blackstone hand pump that uses 1/4" OD tubing, I use a short piece of that with a semi-rigid plastic 3/16" push-rod channel, 36" in length, to go down the dipstick tube. I discovered the push-rod channel, which can be purchased in hobby shops where powered model airplane and boat parts are sold for $0.80 each around here, when looking for a way to get the oil out of a Cadillac Northstar engine that wouldn't let the 1/4 inch tubing go all the way down the dipstick tube. The semi-rigid tube is easy to work with down in the channel, and the top of it makes a good tight fit inside the 1/4 inch tubing that came with the pump. And, I just throw both away after every use as the cost of using new ones is about 1/30th of the cost of the oil analysis and it gets me out of dealing with the mess of trying to clean them out.

 

[scurvy]

Originally Posted By: BBDartCA
For people sucking oil out, are you replacing the suction hose each time to help minimize contamination?


I do with the Blackstone pump, yes. It's cheap enough at the local hardware store (icemaker tubing) and I only need to do so a few times a year. If you're sampling more often, you might consider flushing the tubing with kerosene then brake cleaner.

You always pull one sample bottle full and dump it back in to flush the tubing & container, right? If doing multiple back-to-back samples you could probably pull 2 or 3 bottles full first and take the next one as your sample.

Otherwise on the few occasions I bottom-drain, I'll catch it mid stream during the pan draining.

 

[Quattro Pete]

Blackstone sample pump with a fresh piece of tubing.

 

[Brons2]

Vacuum pump obtained from local Caterpillar dealer for $21. CAT analysis kits include a fresh hose every time and cost $11.something out the door.

 

[21Rouge]

Originally Posted By: ronrackley
When I "suction" it out with the Blackstone hand pump that uses 1/4" OD tubing, I use a short piece of that with a semi-rigid plastic 3/16" push-rod channel, 36" in length, to go down the dipstick tube. I discovered the push-rod channel, which can be purchased in hobby shops where powered model airplane and boat parts are sold for $0.80 each around here, when looking for a way to get the oil out of a Cadillac Northstar engine that wouldn't let the 1/4 inch tubing go all the way down the dipstick tube. The semi-rigid tube is easy to work with down in the channel, and the top of it makes a good tight fit inside the 1/4 inch tubing that came with the pump. And, I just throw both away after every use as the cost of using new ones is about 1/30th of the cost of the oil analysis and it gets me out of dealing with the mess of trying to clean them out.


I just got in from taking such a sample for a used oil analysis and I can vouch today that Ron's technique works just perfectly for those engines for which their is a too significant a bend in the dipstick path to accept the basic 1/4" (too) flexible tubing. This is the case for the GM 3.6L DI engines.

Thanks for the advice RON.

 

[ronrackley]

Originally Posted By: 21Rouge


I just got in from taking such a sample for a used oil analysis and I can vouch today that Ron's technique works just perfectly for those engines for which their is a too significant a bend in the dipstick path to accept the basic 1/4" (too) flexible tubing. This is the case for the GM 3.6L DI engines.

Thanks for the advice RON.


Good.

On my Cadillac Deville Northstars it feels like there is an obstruction, not just a bend, as you try to get enough of the 1/4 inch tubing that is supplied with the vacuum pump down to the oil. It just will not go beyond a certain point. The 3/16 inch semi rigid tube, which I buy at a hobby shop where they sell it to use for control push rods in R/C model airplanes, pushes right on through and makes a snug, air-tight fit inside the end of the short piece of 1/4 inch tubing that is connected to the pump. You can slip it on so that about 1/4 inch of the "push rod" is inside the tubing and pump away.

I wonder why Blackstone doesn't sell them? Are you and I the only two oil testers with engines that have this problem?