Oil extractors - ok to use?

goose1207

Are there any disadvantages to using a pump extractor instead of draining the oil the traditional way? Thanks.

kinley

like I do from the cars because that way, the hot oil rids the crankcase of sludge better than using an extractor.

swschrad

if you are talking about a little pump nobber that goes down the dipstick pipe and pumps the old oil out, the only disadvantages I can think of are the cost of the gizmo and the wait to get the oil out. neither should be serious. have fun with it.

there are service-mechanic pressure flush systems out there that send a shot of solvent into the engine, then flush that out with new oil. there has been a discussion of those on here, and the grizzled mechanics pale at the thought of the machine disturbing gobs of gunk that lie at the end of passages in older engines, all the slop falling to the pan and plugging the oil strainer and pump.

I prefer myself not poking around dark caves with a stick, because you never know what you're going to stir up out of a nap. same thing with the powerflush rigs.

goose1207

I'm talking about the pump type that goes down the dipstick. Is there one that goes down the oil fill area too? Are you really getting all of the old/bad oil out as well as the contaminants when you use a pump as opposed to draining? Thanks.

swschrad

the oil fill on most (domestic) cars goes onto the surface of a cylinder head, for the oil to drain through return galleries to the pan. some cars do have a direct to pan filler, or at least to a spot lower on the block. you typically aren't going to get a tube down a little oil gallery. so don't expect to win with that strategy.

as for pulling out all the oil... I doubt it very much, thanks. in particular, I would not expect a pump extractor to get the sandy crud with the little metal whiskers that is in the bottom of the pan. if the oil isn't warmed up (not hot) when you drail it through the drain plug, you probably won't get rid of that crud by a pan drain, either... not all of it.

but if you do even-numbered oil service with an extractor and let an oil change outfit or the dealer do a pan drain job on the odd numbered ones, the chance of having enough crud to cause trouble is still pretty small.

a reminder that if you don't remove and replace the oil filter with every oil change, there is still a quart of old oil that will remain in the engine. finish the job with a new filter before you turn off the suctioner... taking the old filter off breaks vacuum and there will be some dirty stuff that falls through the pump and into the pan. there will be a spill of dirty oil when you do this... in my (not world-class, and limited to a dozen or so domestics only) experience, if you work slowly enough when actually breaking the gasket seal between the filter and the pump housing, much of the oil will go into the pan, not down your arm.

fleetwoodsimca

...use it! I feel the benefit of the turbulence of warm to hot oil draining through a low point plug opening is a great aid in moving along the settle-out particulates, and getting rid of a lot of them. Using suction pump devices to remove petro fluids (especially automatic transmission fluid) is superseded only by drain plug use. If there is no drain plug, the suction device is good. There is no use breaking seals in cases unless you intend to replace certain filters, inspect moving parts, or scoop out sludge or other crud.

paul29

vaccum it out by way of the dipstick tube . Mercedes has been designed to do it this way for over twenty years .

rubicon52

Years ago, I knew someone with a Honda motorcycle who could not remove the oil drain plug on the bottom of the engine (he damaged it in some way). From then on, he drained the old oil by tipping the bike on its side and letting the old oil drain through the filler hole. This practice eventually destroyed his engine. Seems to me that this method is similar to siphoning through the dipstick hole in that you may not get all the crud on the bottom of the sump as fleetwoodsimca says.

goose1207

everyone has a different opinion on this subject. I don't know if this helps but I would be doing this on a Nissan 3.5L V6 VQ engine and a BMW M62 4.4L V8.

Paul29: Do you know if BMW has designed it the same way as Mercedes?

Thanks.

irishalchemist

to change the ATF fluid in my Mazda 626 - The tranny has no pan to drop, so this is how I do it. I think there is a drain plug somewhere, but the suck-and-fill has worked.

For engine oil I do regular oil changes. However, I am considering alternating a complete change with a suck-and-fill change (changing also the filter...). Only problem is that the dipstick tube may have kink somewhere, and your pump may not be able to get all the way down to the bottom of the pan, and it won't pick up water/coolant that may have found its way into the engine (water is heavier than oil...).

Now, If it does go to the botom, and if the vaccum is good, it should be able to pick up grime pretty good with the oil hot.

Let me know how it goes if you decide to do it. Cheers,

G.

fleetwoodsimca

A good plan: Use the suction method one time, then drain the next.

paul29

Not sure on the BMW but the MB's had a special dipstick tube to which you attached a vacuum hose to the top . It had a couple of o- rings to seal and the tube went to a depression in the pan , as the oil was extracted more flowed to the depression , actually no different than flowing out the drain plug , instead of going down , it went up. The method was shown in the shop manuals . I assumed this was a normal method for changing in Europe.

fleetwoodsimca

http://www.mityvac.com/kits.html#fluidevacuator

I have a Mityvac 6.5 liter vacuum pump that is quite outstanding. It can be used to extract virtually any fluid you desire.