While procrastinating about which Vac-U-Suck to buy, the price on the MityVac shot way up in late June. It had been around $106 but then spiked to $150-$160. Nope. So, I pulled the trigger on the JohnDow 6-gallon unit (
link) for $235 delivered. The MityVac has since dropped back to $122.
I used the JohnDoe for the first time in mid-July, to vacuum oil out of the LR4 Land Rover. The LR4 has a Jaguar AJ133 engine with a metal pipe below the oil fill cap, that is meant for vacuuming oil out. I had to use a 2" length of 1/4" ID rubber hose to connect the JD sucker tube to the LR4 metal pipe, as there's no dipstick or dipstick tube to slide a plastic probe into.
I was pleasantly surprised to find that when the tank was charged to the max vacuum my compressor would provide, it retained that level of vacuum through the entire ~7 quarts extracted, only dropping once the tube started sucking air. No need to recharge part way through the evacuation process. Cool! Took about 5-7 minutes to evacuate - I forgot to time it, but it was kinda slow due to the 4mm ID of the tube. I didn't have time to pull the drain plug and confirm the pan was empty, maybe next oil change, but the amount evacuated matched what I expected.
There are some metal adapter fittings included, and one fits into the top of the dipstick tube of an M119 engine. I'll probably try that and see if anything comes out the drain plug after vacuuming out the M119. Otherwise you slide one of the plastic tubes down the dipstick tubes, which may suck out a bit more. I'm impressed with the JD design & build quality, it appears to be a notch up from the HF unit, maybe 2 notches better. I haven't used the power-empty function yet, I have another oil change to do first (the M119 E420), then I'll see how it does pushing out 3.5 gallons of used oil. Also will be interesting to try evacuating ATF, it should make pulling the 722 pan a lot less messy.
@LWB250 says it is wunderbar for ATF work, which is a bonus.
Pro tip: If you want to know exactly how much oil was extracted, the side measuring tube is kinda useless... graduations begin at over 6 quarts. I weigh the evacuator before and after on my refrigerant scale to measure the weight of the oil extracted. Divide that number by the weight per quart / gallon of new stuff and you get a close estimate of quarts evacuated. Ballpark is 1.85 pounds per quart, excluding container weight.
In other news, the factory JLR oil filter media separated from the mesh pleating in one small area, allowing unfiltered oil to circulate for an unknown time / miles. GREAT. I need to get some photos of that. Not happy about the OE / Genuine filter failure... they are made in China, but I can't find anything better, and aftermarket filters could just be the factory rejects. Spendy buggers too, $20-$30 each at discount, grrrr. Oil analysis came in a couple days ago, thankfully there were no red flags, all looked normal despite the filter failure.
I'll post again after sucking out the M119 sump, and using pressure to empty the JohnDoe tank into plastic jugs.
