Weekend LiquiVac Oil Changes

[olehholy]

I thought I would share my experience this weekend conducting 2 MB oil changes. One on a 2002 E430 4-Matic and one on 1984 300D Turbo. In both cases I used a device called a LiquiVac, which is a popular home "topsider" oil removal system based on a tank and a hand vacuum pump. I chose this method becasue it seems that the E430 has an undercarriage plate blocking the oil pan drain plug which I did not feel like futzing with this weekend. Here are my observations:

1. Definetly cut the pickup tube end at a 45-degree angle to prevent it from butting up againt the side of the oil pan and blocking itself up.

2. Temperature of the oil in the engine is key. Too cold, and it will draw out impossibly slow and you wont get it all out. Too hot, and it will soften the plastic tube going into the tank and the tube will collapse upon itself, thus slowing down the suction.

3. On the E430 it worked reasonably well. Becasue the new E430 uses 0W-40 which is like water, the oil ran quickly, in about 17 minutes. I did have this oil too hot though so it softened the flex tubing too much and I had to fight it a little.

4. On the 300D, things went much slower. The thicker oil needed allot more vaccum but there is a trade-off. Too much vaccum and the tubing will again collapse on itself and the oil will go down to a trickle. It took about 40 minutes for the 300D to complete.

5. In both cases, the unit did get all the oil out, surprisingly. I measured the spent oil and it was on the mark as per capacity, right around 8 quarts in both cases.

6. I am going to do some improvments to this device. I am going to replace the flexible plastic tubing with rigid tubing all the way, not just the pickup tube section. This should reduce the tendancy for the tuging to collapse on itself.

Just my 2 cents.

Oleh

[nhodges]

Please let us know what you use as a rigid tube and how well it works. iI am considering buying the liquivac.

[pmizell]

Yes, please let us know the tubing you end up using.

I change my oil when it's pretty hot and the small 3' or so section of tubing nearest to the sump collapses very easily.

Good luck!

[nglitz]

Just for grins, I did a Google search on LiquiVac. Looks like AirPowerAmerica sells all three varieties of these suckers. Including a refurbished topsider and parts.

Neat! I may just hafta get one.

[d2bernhard]

MityVac is the unit of choice.

Best place to buy Topsider or equivalent in Virginia?

MVP Topsider where to buy?

[Bob I]

Here is another prior thread on the subject: MityVac discussion