Mityvac vacuum pump

[Guest]

http://mityvac.com/pages/products_hvpk.asp

I'm considering buying the model 4000 for brake bleeding. I would also use for my other vehicles but was wondering if this is sturdy enough to vacuum out 80w-90 gear oil(or heavier) from various gear boxes, rear ends, differentials, 4x4 transfer cases, etc...that don't have drain plugs?
I've seen the Mityvac mentioned here on the forum for brake bleeding, so I thought I'd ask for some reviews before buying. They seem to be priced in the $45-60 range online but are they available at the local parts store?

[Steve]

Yes, they are available at the local auto parts store, at least they are at my local Auto Zone and Pep Boys. I don't know about which model number is what, but I have the plastic one that works quite well. I think it cost about $35-40 several years ago, the metal ones are about $75 or so.

Is it robust enough to handle gear oil? Yes, as it's not going to touch the oil. The oil gets caught in a jar before it gets to the pump. The real question should be "Do I want to squeeze the handle that many times to drain the oil?" It takes several squeezes of the handle to build vacuum to draw fluids into the jar. Your hand will get tired rather quickly. The rear ends of our bikes only hold a few ounces of fluid, and that's not bad to suck out. A 4x4 transfer case holds at least a couple of quarts, doesn't it? I don't want to be the one to have to squeeze the handle that many times. :shock:

I just looked at their site and was wondering if maybe the model 7240 Fluid Transfer Pump might to better for you?

Another option would be either the model 7400 Fluid Evacuator or 7201 Fluid Evacuator Plus.
These are made to transfer larger quantities of fluid, but don't appear to be well-suited for bleeding your brakes.

.

[brand new bike zealot]

I've had my mity vac for a couple years and am extremely pleased with how easy brake bleeding now is. No procrastination when the fluid starts looking a little dark. I'd have to agree that it may not be the best bet for gear oil due solely to capacity. The container on mine is maybe 250ml or so. Enough for a solid flushing, but it may take a few goes for the gear oil job.

[SPARKSS]

http://mityvac.com/pages/products_hvpk.asp

I'm considering buying the model 4000 for brake bleeding. I would also use for my other vehicles but was wondering if this is sturdy enough to vacuum out 80w-90 gear oil(or heavier) from various gear boxes, rear ends, differentials, 4x4 transfer cases, etc...that don't have drain plugs?
I've seen the Mityvac mentioned here on the forum for brake bleeding, so I thought I'd ask for some reviews before buying. They seem to be priced in the $45-60 range online but are they available at the local parts store?

Hi Lurch......I'll concur with Steve's assessment of the Mity-Vac. For heavier oils, in small amounts (up to a few litres) there are quite a few typical suction-gun type tools available quite cheaply through the usual automotive suppliers - they often look like a hand grease gun barrel with a hose inlet etc...some fancier ones have an inlet 'n outlet with check valving (for transfer).. The Mity-Vac will do a fine job (with the vacuum jar) on brake fluid, though I've never needed to use it on brakes myself. I have used it with good success on stubborn hyd clutches though (Ford Grrrrreat design!) and of course to test many types of vacuum circuits in general.

I'd have to say, having worked on a lot of gearboxes (industrial 'n automotive), diffs and transmissions that usually there are drain plugs or drain bolts (may be part of a cover or subassembly) OR a cover is removed easily for draining and cleanout. A suction gun on any one of these, for other than top up would be a poor choice for completely draining.

[Escobarclan]

dude, i've tried using my vac for heavier oils, not worth it. but good for brakes and other applications.

[lurch12_2000]

thanks for the replies.
Check pg 4 on this doc to see what I'm talking about using the mityvac.

http://home.ripway.com/2005-4/294125/Volvo/V70XCBevelGear.pdf

I know this a bike forum, but there is no drain plug or cover to remove to drain my '96 GMC Jimmy front differential. Other than using a vacuum pump you would have to drop the front axles and drop and break open the case housing to get fluid out.
I could warm it up to flow easier through the pump?...
and still use it for my GS brakes too?

[Steve]

I have always avoided pumping fluid through the MityVac. I figured there was a catch bottle in the system for a reason, so I continue to use it. I suppose that pumping through the MityVac would be more efficient for moving large quantities, as each stroke would move that much fluid, not just build up vacuum to suck it into the catch bottle.

Try it, let us know how it works. 8-[ If it doesn't work, it's only $40 wasted.

.

[lurch12_2000]

follow up...

Just in case you need to apply this to working on your bikes.
I skipped buying a Mityvac based on opinions here that it wouldn't handle pumping out old 80w-90 gear oil because it was labor intensive and too thick.
Instead I bought an $8 drill pump attachment at Home Depot. It was labelled for use with water or engine oil so I thought I'd try with the gear oil. I used my 3/8" drive electric drill (my cordless didn't produce enough rpms as the battery needed charging) and two 5/8" screw-on garden hose attachments I found lying around the house, two 18" pieces of 5/8" OD clear tubing also lying around the house, and two 1/2 gallon cleaned clear plastic juice bottles from my recycle bin(or soda bottles would work).

Jacked up the Jimmy, pulled the fill plug, inserted the "IN" side tube as far down as possible into the front differential, put the "OUT" side tube in the empty plastic bottle, and within 20 seconds I had the 2+ pints sucked out.
Measured the same amount of new 80w-90 GL-5 gear oil into the other clean plastic bottle and within 15 seconds I had the bottle emptied and the differential case filled. Old oil looked original (110k miles).
You may use a short section of thinner tubing if the opening is too narrow. Just insert a 6-8" piece of 3/8" tubing about 1/2" into the "IN" side of the 5/8" tubing and duct tape together.
see attached pic...

[lurch12_2000]

also...

after I finished I filled a bucket with warm water and a little dish soap and ran the drill for a few minutes to flush out and clean the pump before putting it away for the next time.