Transaxle Oil Change. Fourth try is a charm???

[Chuggs]

So, I enjoy doing my own annual maintenance on our 2016 Newmar Ventana. I have the tools, generally, to make the work go well, for the most part.

The one task I kept saying to myself..."There has to be a better way!" ... was transaxle oil changes. I started on the second year buying gallon jugs of Mobil 1 Delvac ...and one of those hand pumps that fit on the jugs. It felt like it took 10,000 strokes to transfer 23 pints into the pumpkin. I vowed to find a better way. Three years later, and year 5 maintenance...I bought a little 12v oil pump. I was excited at first not to be dreading the 10,000 strokes with a hand pump. Got the 12v transfer pump all hooked up, and all it did was make bubbles in the oil. It would not transfer the 75w-90 weight oil at all. Then I finished the job with...you guessed it! 10,000 strokes with the hand pump. Shortly after that fiasco...I tripped across an Amazon listing for a pnuematic oil transfer pump. It had been used once and returned...so they offered it for a substantial discount. I purchased it and set it aside for the next time I needed to fill a transaxle. I had thought about the lever action pumps you mount to a 5 gallon bucket...but it would take two people...one to pump, and one to be under the coach to determine when filling is complete. I figured this pnuematic thing was going to be the ticket. Along comes year 8 maintenance. I get busy modifying an expired propane cylinder... I add the oil, the pump head, shop air...adjust the regulator... and well ...trickle....slow, slow trickle. At least I'm not pumping by hand 10,000 strokes...but NOT impressed. The pump has a knob you turn one direction to fill a drum (extract) and the other direction to dispense from the drum. The first uses your shop air thru a venturi device to draw fluid in by creating a vacuum source...the later puts postive air into the drum to dispense. But mine leaks air when dispensing...so I cannot build much pressure.

I had an email exchange with the vendor. They explained it would not pump Gear Oil...and I told them the unit was defective. Even though I was way past any return window...they did offer to give me a refund. I told them I wanted it...but needed to fix it. They offered to send any parts I needed. When I disassembled the venturi body...I could see the leak was by design. It would be dangerous to put too much pressure into a large metal or plastic drum...so, there is a vent channel cut in the seat end of the valve. Now knowing how the unit came up short for my needs...I ordered a 3/8" bsp plug...and plugged the port where the Venturi valve body goes. I can't use the device to extract oil...which I had no desire to do anyway. Now I can deliver 100% of the regulated air pressure into the tank...to push the gear oil along at a good rate. I am finally not dreading year 11 maintenance, when it is again time to change transaxle oil.

DANGER!!!! If you get the crazy idea to make one of these contraptions...you need to realize the risks involved too. 1) welding on old propane cylinders is dangerous. Propane gets into the pores of the cylinder walls...and no matter how well you drain and flush...when you heat it...it will find fuel. Some folks recommend putting the tank on a vacuum, filling with inert gas, let sit...repeat, etc...before they ever take a torch to one. That said...be careful not to create a fragmentation bomb. 2) Although a propane cylinder can withstand well over the average 125 psi shop compressor...welding makes steel brittle. You would need to heat treat all welds to get the best strength...but we aren't going for 200+ psi here. Just be careful if pressurizing a modified cylinder.

Anyway, I finally have this thing dialed in for year 11...

I'll attach a link and some photos...

FIRSTINFO A1181US Pneumatic High Flow Oil Barrel Drum Pump, Two-Way Air Operated Oil Transfer Extractor & Dispenser (1:1) for 50 Gallon (200 Liter) Metal Tank Amazon.com