# Fluid pump



## rhanna (Jun 7, 2017)

I ordered 1 pump to use in transferring fluids like transmission fluid and transfer case fluid, differentials. 
I know it's a dumb question but how thorough does the pump need to be cleaned when switching fluids?


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## 440mag (Jan 29, 2018)

There are no dumb questions ...

Are you using the pump to transfer "clean, new" fluids from a "new" container into a machine where the fluid would be used?

If that is the case I'd really, really let my answer be driven by how close the different fluids are to one another.

I'd also let the dollar amount of replacing any internals dictate whether or not it wouldn't simply be cheaper for me to buy a transfer pump for each type of fluid and simply Mark it! (That is why a relative who farms has several liquid transfer pumps hanging over the edges in a 35-gal drum and each one is marked with permanent marker as to what fluid it is for transferring.)

The transmission in the '73 pictured requires an extremely heavy oil and given the trans is actually original to the car (probably the only thing that is but, still) I would never move "other" fluids through the pump I use to refill that trans.

I many instances, a pump is cheaper than the fluids one is transferring, let alone what they're being transferred INTO!

If you're only using the pump to extract old, "used" fluids, I guess the answer depends upon what will you be doing with the extracted fluids?

1) If you're going to be re-using them (highly unlikely but ...) then the need to completely clean out the receptacle is so critical I'd wager it warrants a separate pump for each type fluid (at least any type that you intend to put back in a machine!)

2) if you're going to be simply recycling the fluids then I would just allow the pump to drain as completely as possible over say, 10-15 mins. (I just used one of these pumps to extract the oil out of a push mower and I find a way to safely (securely) "prop" the drain upside down so it is draining into a funnel inserted into the old 5-quart oil jug I use to run old oil to the recycler center. I set that up as soon as I finish using the pump so it has a good 15-20 mins to drain while I complete refilling the motor, cleanup, etc., etc.

Same goes for transmission fluid - I don't "clean out" the pump reservoir , I simply let it drain really well.

I use low/no odor mineral spirits to clean guns and use the same jug to run old, dirty mineral spirits to a different recycle center that I use for runs to the oil recycler. I don't "clean out" the jug in between uses BUT! I do allow the container to really, REALLY drain empty as completely as is possible / practible ...


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## rhanna (Jun 7, 2017)

Thanks for the detailed response. I think I will be using different pumps for each. I found them on sale at harbor freight and I'll just leave them in a gallon zip lock bag labeled.

It's mainly for the Jeep we recently bought. I'm not sure when the last time the prior owner changed the fluids and it isn't super expensive if you are doing them at home


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